Patent Publication Number: US-2017371249-A1

Title: Exposure apparatus and exposure method, and device manufacturing method

Description:
This is a Divisional of U.S. patent application Ser. No. 13/727,229 filed Dec. 26, 2012. The entire disclosure of the above-mentioned prior application is hereby incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to exposure apparatuses, exposure methods and device manufacturing methods, and more particularly to an exposure apparatus and an exposure method used in a lithography process to manufacture electron devices (microdevices), and a device manufacturing method using the exposure apparatus or the exposure method. 
     Description of the Background Art 
     Conventionally, in a lithography process to manufacture electron devices (microdevices) such as a semiconductor device (an integrated circuit and the like), a liquid crystal display device and the like, a projection exposure apparatus employing a step-and-repeat method (a so-called stepper), or a projection exposure apparatus employing a step-and-scan method (so-called scanning stepper (also called a scanner)) is mainly used. 
     In this type of exposure apparatus, in general, a position of a wafer stage which moves two-dimensionally while holding a substrate such as a wafer or a glass plate or the like (hereinafter collectively called a wafer) on which a pattern is transferred (or formed) was measured, using a laser interferometer. However, due to finer patterns accompanying higher integration of semiconductor devices in recent years, requirements for position control performance of a wafer stage with higher accuracy have increased, and as a consequence, it has become difficult to ignore short-term variation of measurement values caused by air fluctuation which occurs due to the influence of temperature change and/or temperature gradient of the atmosphere on the beam path of a laser interferometer. 
     To improve such inconveniences, various proposals have been made of inventions related to exposure apparatuses that employ an encoder having a measurement resolution of the same level as or a higher level than a laser interferometer, as a position measurement device of a wafer stage (for example, refer to U.S. Patent Application Publication No. 2008/0088843). However, in the liquid immersion exposure apparatus disclosed in U.S. Patent Application Publication No. 2008/0088843 and the like, for example, the wafer stage (gratings provided on the upper surface of the wafer stage) may be deformed influenced by heat of vaporization and the like due to the liquid evaporating, and there still was room for improvement. 
     As an exposure apparatus to improve such inconveniences, an exposure apparatus has been known in which an exposure station where exposure of a wafer is performed and a measurement station where measurement operations such as wafer alignment are performed are each equipped with an encoder system which irradiates a measurement beam on a grating provided on a rear surface of a table that holds a wafer, from a head section provided at the tip of a measurement arm made up of a cantilever (for example, refer to U.S. Patent Application Publication No. 2010/0296070). 
     However, in the exposure apparatus disclosed in U.S. Patent Application Publication No. 2010/0296070, a structure is employed in which, for example, a fine movement stage (wafer table) that holds a wafer is exchanged between two coarse movement stages via an intermediate member (for example, a center table, a relay stage, or the like). Therefore, there is a risk that such wafer exchange causes decrease in throughput of the apparatus. The wafer size is gradually increasing, and in the impending era of a 450 mm-wafer with a diameter of 450 mm, it is expected that further improvement in throughput is required, and accordingly it becomes difficult to cope with such requirement with the table exchange method as described above. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the present invention, there is provided a first exposure apparatus that exposes an object by an energy beam via an optical system, the apparatus comprising: a first moving member and a second moving member that each hold the object and are movable independently from each other in an area within a predetermined plane, and each have a first grating provided at a position under a surface where the object is mounted, the area including an exposure station where exposure of the object by the energy beam is performed and a measurement station which is placed away from the exposure station in a first direction parallel to the predetermined plane and where a predetermined measurement on the object is performed; a first measurement system that is provided at the exposure station, has a first measurement member with the first direction serving as a longitudinal direction, and by irradiating from below a first measurement beam from the first measurement member onto the first grating of a moving member located at the exposure station, of the first and the second moving members, measures first position information of the moving member located at the exposure station; a second measurement system that is provided at the measurement station, has a second measurement member with the first direction serving as a longitudinal direction, and by irradiating from below a second measurement beam from the second measurement member onto the first grating of a moving member located at the measurement station, of the first and the second moving members, measures second position information of the moving member located at the measurement station; a third moving member which is movable independently from the first and the second moving members within the predetermined plane and includes a light-receiving plane that receives the energy beam via the optical system, and at which an optical member that is at least a part of a measurement device that performs a measurement related to exposure based on a light-receiving result of the energy beam received via the light-receiving plane is provided; and a drive system that individually drives the first, the second and the third moving members. 
     According to this apparatus, the drive system individually drives the first, the second and the third moving members, and for example, when one of the first moving member and the second moving member that holds the object that has undergone exposure is moved apart from the exposure station and the other of the first moving member and the second moving member that holds an object on which a predetermined measurement has been performed in the measurement station is located between the measurement station and the exposure station, the third moving member is moved to under the optical system. Accordingly, during a period after the exposure of the object held by the one of the moving members has been completed until exposure of the object held by the other moving member is started, measurement related to exposure can be performed in the exposure station by the measurement device based on the light-receiving result of the energy beam received via the light-receiving plane. This allows necessary measurement related to exposure to be performed using the movement time (and/or waiting time) of the first and the second moving members in between exposures. Therefore, the necessary measurement related to exposure can be performed without reducing the throughput. 
     According to a second aspect of the present invention, there is provided a device manufacturing method, comprising: exposing an object using the first exposure apparatus described above; and developing the object that has been exposed. 
     According to a third aspect of the present invention, there is provided a second exposure apparatus that exposes a substrate via an optical system, the apparatus comprising: a first stage and a second stage, each of which has a holding member that has a mounting area of the substrate provided on an upper surface side and a first grating member provided on a lower surface side, and a main section that supports the holding member so that a space is formed under the first grating member; a third stage different from the first and the second stages, that is placed at an exposure station where exposure of the substrate is performed via the optical system; a detection system placed at a measurement station different from the exposure station, that detects position information of the substrate by irradiating the substrate with a detection beam; a drive system that moves the first, the second and the third stages, and also moves each of the first and the second stages from one of the exposure station and the measurement station to the other; a first measurement system that has a first head section provided at the exposure station and a second head section provided at the measurement station, and that irradiates the first grating member with a first measurement beam from below via the first head section that is placed in the space by one of the first and the second stages placed at the exposure station being positioned facing the optical system and measures position information of the one of the stages, and also irradiates the first grating member with a first measurement beam from below via the second head section that is placed in the space by the other of the first and the second stages placed at the measurement station being positioned facing the detection system and measures position information of the other of the stages; and a controller that controls drive of the first and the second stages by the drive system, based on the position information measured by the first measurement system, in order to move each of the first and the second stages in the exposure station and in the measurement station, wherein the controller moves each of the first and the second stages from one of the exposure station and the measurement station to the other using the drive system so that instead of one of the first and the second head sections placed in the space, the other of the first and the second head sections is placed in the space. 
     According to this apparatus, the controller moves each of the first and the second stages by the drive system from one of the exposure station and the measurement station to the other so that in replacement of one of the first and the second heads placed in the space, the other of the first and the second heads is placed. 
     According to a fourth aspect of the present invention, there is provided a device manufacturing method, comprising: exposing a substrate using the second exposure apparatus described above; and developing the substrate that has been exposed. 
     According to a fifth aspect of the present invention, there is provided an exposure method of exposing a substrate via an optical system, the method comprising: positioning one of a first stage and a second stage to face the optical system in an exposure station, each of the first stage and the second stage having a holding member that has a mounting area of the substrate provided on an upper surface side and a first grating member provided on a lower surface side, and a main section that supports the holding member so that a space is formed under the first grating member, and in the exposure station a third stage different from the first and the second stages being placed and exposure of the substrate being performed via the optical system; measuring position information of the one of the stages by a first measurement system that irradiates the first grating member with a first measurement beam from below via a first head section placed in the space of the one of the stages positioned facing the optical system, in order to move the one of the stages in the exposure station; measuring position information of the other of the stages by the first measurement system that irradiates the first grating member with a first measurement beam from below via a second head section placed in the space of the other of the stages positioned facing a detection system that detects position information of the substrate by irradiating the substrate with a detection beam, in order to move the other of the stages in a measurement station which is different from the exposure station and where the detection system is placed; and moving the other of the stages to cause the first head section to proceed inside the space, following movement of the one of the stages to withdraw the first head section from inside the space, so that instead of the one of the stages, the other of the stages that is moved from the measurement station to the exposure station is positioned facing the optical system. 
     According to a sixth aspect of the present invention, there is provided a device manufacturing method, comprising: exposing a substrate using the exposure method described above; and developing the substrate that has been exposed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       In the accompanying drawings; 
         FIG. 1  is a view schematically showing a structure of an exposure apparatus related to an embodiment; 
         FIG. 2  is a schematic plan view of the exposure apparatus in  FIG. 1 ; 
         FIG. 3A  is a plan view showing a wafer stage in  FIG. 1 , and  FIG. 3B  is a view (front view) of the wafer stage when viewed from a −Y direction; 
         FIG. 4A  is a view (front view) of a measurement stage in  FIG. 1  when viewed from the −Y direction, and  FIG. 4B  is a plan view showing measurement stage MST; 
         FIG. 5  is a view showing a placement of a first to a third top side encoder systems, an alignment detection system, an AF system and the like that the exposure apparatus in  FIG. 1  is equipped with, with a projection optical system serving as a reference; 
         FIG. 6  is a block diagram showing an input/output relation of a main controller mainly structuring a control system of the exposure apparatus related to the embodiment; 
         FIG. 7  is a view showing an example of a concrete structure of a first and a second fine movement stage position measurement systems in  FIG. 6 ; 
         FIG. 8A  is a perspective view showing the tip of a measurement arm of a first back side encoder system, and  FIG. 8B  is a plan view showing the tip of the measurement arm in  FIG. 8A ; 
         FIG. 9  is a view (No. 1) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 10  is a view (No. 2) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 11  is a view (No. 3) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 12  is a view (No. 4) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 13  is a view (No. 5) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 14  is a view (No. 6) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 15  is a view (No. 7) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 16  is a view (No. 8) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 17  is a view (No. 9) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 18  is a view (No. 10) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 19  is a view (No. 11) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 20  is a view (No. 12) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 21  is a view (No. 1) used to describe a structure of an exposure apparatus related to a modified example, and also used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST; 
         FIG. 22  is a view (No; 2) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST performed in the exposure apparatus related to the modified example; 
         FIG. 23  is a view (No. 3) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST performed in the exposure apparatus related to the modified example; and 
         FIG. 24  is a view (No. 4) used to describe a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST performed in the exposure apparatus related to the modified example. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, an embodiment will be described, based on  FIGS. 1 to 20 . 
       FIG. 1  schematically shows a structure of an exposure apparatus  100  related to the embodiment.  FIG. 2  shows a schematic plan view of exposure apparatus  100 . Exposure apparatus  100  is a projection exposure apparatus employing a step-and-scan method, which is a so-called scanner. As it will be described later on, in the present embodiment, a projection optical system PL is provided, and hereinafter, the description will be made with a direction parallel to an optical axis AX of this projection optical system PL referred to as a Z-axis direction (Z direction), a direction in which a reticle and a wafer are relatively scanned within a plane orthogonal to the Z-axis direction referred to as a Y-axis direction (Y direction), and a direction orthogonal to the Z-axis and the Y-axis referred to as an X-axis direction (X direction), and rotation (tilt) directions around the X-axis, the Y-axis, and the Z-axis referred to as θx, θy, and θz directions, respectively. 
     Exposure apparatus  100 , as shown in  FIG. 1 , is equipped with an exposure section  200  placed near the edge on the +Y side on a base board  12 , a measurement section  300  placed near the edge on the −Y side on base board  12 , two wafer stages WST 1  and WST 2  and a measurement stage MST which move two-dimensionally within an XY-plane independently from one another on base board  12 , a control system for these sections, and the like. In the description below, for the sake of convenience, as the terms to indicate each place of exposure section  200  and measurement section  300 , the places will be called exposure station  200  and measurement station  300 , using the same reference signs. 
     Base board  12  is supported in a substantially horizontal manner (parallel to the XY-plane) on a floor surface by a vibration-proof mechanism (omitted in the drawings). Base board  12  is made up of a member having a flat plate outer shape. Incidentally, in  FIG. 1 , wafer stage WST 1  is positioned at exposure station  200  and wafer stage WST 2  is positioned at measurement station  300 , and a wafer W is held on each of wafer stages WST 1  and WST 2  (to be more specific, on a wafer table to be described later on). Further, measurement stage MST is positioned in exposure station  200  or in the vicinity of exposure station  200 . Measurement stage MST is positioned at a predetermined position (withdrawal position or standby position) that is set apart from a position below projection optical system PL so that measurement stage MST does not come into contact with wafer stages WST 1  and WST 2  that are moved below projection optical system PL during an exposure operation of wafer W in which wafer stages WST 1  and WST 2  are each used. Further, prior to completion of the exposure operation of wafer W, measurement stage MST is moved relative to one of wafer stages WST 1  and WST 2  that is moved below projection optical system PL to approach the one of wafer stages WST 1  and WST 2 , and at the time of the completion of the exposure operation at the latest, the one of the wafer stages and measurement state MST are positioned in proximity to (or contact with) each other. Moreover, the one of the stages and measurement stages MST in proximity to each other are moved with respect to projection optical system PL, and measurement stage MST is placed facing projection optical system PL instead of the one of the wafer stages. Incidentally, it is also possible that at least a part of the relative movement to position the one of the wafer stages and measurement stage MST in proximity is performed after the exposure operation of wafer W. 
     Exposure section  200  is equipped with an illumination system  10 , a reticle stage RST, a projection unit PU, a local liquid immersion device  8  and the like. 
     Illumination system  10 , as disclosed in, for example, U.S. Patent Application Publication No. 2003/0025890 and the like, includes a light source; and an illumination optical system which has an illuminance equalizing optical system including an optical integrator and the like, and a reticle blind and the like (none of which are shown). Illumination system  10  illuminates a slit-shaped illumination area IAR on a reticle R set (limited) by a reticle blind (also called a masking system) with illumination light (exposure light) IL at a substantially equal illuminance. Here, as illumination light IL, as an example, an ArF excimer laser beam (wavelength 193 nm) is used. 
     On reticle stage RST, reticle R that has a circuit pattern and the like formed on its pattern surface (the lower surface in  FIG. 1 ) is fixed, for example, by vacuum chucking. Reticle stage RST is finely drivable within the XY-plane and is also drivable in a scanning direction (the Y-axis direction, which is the lateral direction of the page surface of  FIG. 1 ) at a predetermined scanning velocity, by a reticle stage driving system  11  (not shown in  FIG. 1 , refer to  FIG. 6 ) including, for example, a linear motor and the like. 
     Position information within the XY-plane (including rotational information in the θz direction) of reticle stage RST is constantly detected, using a reticle laser interferometer (hereinafter referred to as a “reticle interferometer”)  13  via a movable mirror  15  (a Y movable mirror (or a retroreflector) having a reflection surface orthogonal to the Y-axis direction and an X movable mirror having a reflection surface orthogonal to the X-axis direction are actually provided) fixed to reticle stage RST, at a resolution of, for example, around 0.25 nm. Measurement values of reticle interferometer  13  are sent to a main controller  20  (not shown in  FIG. 1 , refer to  FIG. 6 ). Incidentally, the position information of reticule stage RST can be measured using an encoder system disclosed in, for example, U.S. Pat. No. 7,839,485 and the like, instead of reticle interferometer  13 . In this case, one of a grating member (a scale plate, or a grid plate) where a grating is formed and an encoder head can be provided on a lower surface side of reticle stage RST and the other can be placed under reticle stage RST, or one of the grating member and the encoder head can be provided on an upper surface side of reticle stage RST and the other can be placed above reticle stage RST. Further, reticle stage RST can employ a coarse-fine movement structure similar to wafer stage WST to be described later on. 
     Projection unit PU is placed below reticle stage RST in  FIG. 1 . Projection unit PU is supported by a main frame (metrology frame) BD, which is supported horizontally by a support member not shown, via a flange section FLG provided on the outer circumference portion of the projection unit. Main frame BD structures a part of a main body frame of exposure apparatus  100  where at least a part of the illumination optical system and reticle stage RST are mounted, and in the present embodiment, main frame BD is supported by a plurality of (for example, three or four) support members (not shown) placed on a installation surface (for example, a floor surface or the like) each via a vibration-proof mechanism. Incidentally, on the installation surface, based board  12  to be described late on and the like are also placed. Further, the vibration-proof mechanism can be placed between each support member and main framed BD. Furthermore, as disclosed in, for example, PCT International Publication No. 2006/038952, projection unit PU can be supported in a suspended manner with respect to a part of the main body frame placed above projection unit PU. 
     Projection unit PU includes a barrel  40 , and projection optical system PL held within barrel  40 . As projection optical system PL, for example, a dioptric system is used that is made up of a plurality of optical elements (lens elements) disposed along optical axis AX parallel to the Z-axis. Projection optical system PL, for example, is telecentric on both sides, and has a predetermined projection magnification (e.g., ¼, ⅕, or ⅛ or the like). Therefore, when illumination area IAR on reticle R is illuminated by illumination light IL from illumination system  10 , by illumination light IL which passes through reticle R placed so that a first plane (object plane) of projection optical system PL and the pattern surface are substantially coincident, a reduced image of a circuit pattern (a reduced image of part of a circuit pattern) within illumination area IAR of reticle R is formed via projection optical system PL (projection unit PU), in an area (hereinafter also referred to as an exposure area) IA, conjugate to illumination area IAR, on wafer W which is placed on a second plane (image plane) side of projection optical system PL and whose surface is coated with a resist (sensitive agent). And, by synchronously driving reticle stage RST and wafer stage WST 1  or WST 2  (to be more accurate, a fine movement stage WFS to be described later holding wafer W), reticle R is relatively moved in the scanning direction (Y-axis direction) with respect to illumination area IAR (illumination light IL), while wafer W is relatively moved in the scanning direction (Y-axis direction) with respect to exposure area IA (illumination light IL), and thereby scanning exposure of a shot area (divided area) on wafer W is performed and the pattern of reticle R is transferred onto the shot area. That is, in the present embodiment, the pattern of reticle R is generated on wafer W using illumination system  10  and projection optical system PL, and the pattern is formed on wafer W by exposing a sensitive layer (resist layer) on wafer W with illumination light IL. 
     Local liquid immersion device  8  is provided, corresponding to exposure apparatus  100  performing exposure based on a liquid immersion method. Local liquid immersion device  8  includes a liquid supply device  5 , a liquid recovery device  6  (none of which are shown in  FIG. 1 , refer to  FIG. 6 ), a nozzle unit  32  and the like. Nozzle unit  32 , as shown in  FIG. 1 , is supported in a suspended manner by main frame BD supporting projection unit PU and the like, via a support member not shown, and surrounds the periphery of the lower end section of barrel  40  holding an optical element which structures projection optical system PL closest to the image plane side (wafer W side), in this case, a lens (also referred to as a “tip lens” or “final lens”)  191 . Nozzle unit  32  is equipped with a supply port and a recovery port of a liquid Lq, a lower surface where wafer W faces and in which a recovery port is provided, a liquid supply pipe  31 A and a liquid recovery pipe  31 B (none of which are shown in  FIG. 1 , refer to  FIG. 2 ) and a supply passage and a recovery passage connected to the pipes, respectively. Liquid supply pipe  31 A is connected to one end of a supply pipe which is not shown whose other end is connected to liquid supply device  5  (not shown in  FIG. 1 , refer to  FIG. 6 ), and liquid recovery pipe  31 B is connected to one end of a recovery pipe which is not shown whose other end is connected to liquid recovery device  6  (not shown in  FIG. 1 , refer to  FIG. 6 ). Further, nozzle unit  32  has the supply passage and the recovery passage inside, and liquid supply pipe  31 A and liquid recovery pipe  31 B are connected to the supply port and the recovery port via the supply passage and the recovery passage, respectively. Further, nozzle unit  32  has an opening section, through which illumination light IL emitted from projection optical system PL passes, in its lower surface, and the recovery port is placed in the periphery of the opening section. While, in the present embodiment, the supply port is provided on an inner side surface of nozzle unit  32  that surrounds the tip lens, another supply port can be provided separately from the supply port, on an inner side than the recovery port with respect to the opening section on a lower surface side of nozzle unit  32 . 
     In the present embodiment, main controller  20  controls liquid supply device  5  (refer to  FIG. 6 ) and supplies liquid to between tip lens  191  and wafer W via liquid supply pipe  31 A and nozzle unit  32 , and also controls liquid recovery device  6  (refer to  FIG. 6 ) and recovers liquid from between tip lens  191  and wafer W via nozzle unit  32  and liquid recovery pipe  31 B. On this operation, main controller  20  controls liquid supply device  5  and liquid recovery device  6  so that the amount of the liquid supplied and the amount of the liquid recovered are constantly equal. Accordingly, a fixed quantity of liquid Lq (refer to  FIG. 1 ) is constantly replaced and held between tip lens  191  and wafer W. Local liquid immersion device  8  forms a liquid immersion area under projection optical system PL by liquid Lq that local liquid immersion device  8  supplies via nozzle unit  32 , and also can hold liquid Lq only at a part of wafer W by recovering the liquid from the liquid immersion area via nozzle unit  32 , that is, can form the liquid immersion area by confining liquid Lq within a local area that is smaller than the upper surface of wafer stage WST 1  or WST 2  (fine movement stage WFS) placed facing projection optical system PL, and therefore, smaller than the surface of wafer W. Therefore, nozzle unit  32  can also be called a liquid immersion member, a liquid immersion space forming member, a liquid confinement member, or a liquid containment member, or the like. In the present embodiment, as the liquid above, pure water which transmits the ArF excimer laser beam (light having a wavelength of 193 nm) is used. Incidentally, refractive index n of the pure water to the ArF excimer laser beam is about 1.44, and in the pure water, the wavelength of illumination light IL is shortened to 193 nm×1/n=around 134 nm. 
     While, in the present embodiment, nozzle unit  32  is supported in a suspended manner by main frame BD, nozzle unit  32  can be provided at a frame member different from main frame BD, for example, a frame member that is placed on the installation surface described previously, separately from main frame BD. With this arrangement, vibration transmitted from nozzle unit  32  to projection optical system PL can be suppressed or prevented. Further, it is also possible that a part of nozzle unit  32  that comes into contact with liquid Lq (an interface of the liquid immersion area) on the lower surface side of nozzle unit  32  is made to be movable, and the part of nozzle unit  32  is moved so that the relative velocity between wafer stage WST 1  or WST 2  and nozzle unit  32  is reduced during movement of wafer stage WST 1  or WST 2 . This can suppress or prevent a part of liquid Lq from being separated from the liquid immersion area and remaining on the upper surface of wafer stage WST 1  or WST 2 , or on the surface of wafer W, especially during an exposure operation of wafer W. In this case, during movement of wafer stage WST 1  or WST 2 , the part of nozzle unit  32  may constantly be moved, or only during a part of the exposure operation, for example, only during a stepping operation of wafer stage WST 1  or WST 2 , the part of nozzle unit  32  may be moved. Further, the part of nozzle unit  32  can be, for example, a movable unit having the recovery port and at least a part of the lower surface, or a plate that is relatively movable with respect to nozzle unit  32  and has a lower surface in contact with the liquid. 
     Besides this, exposure section  200  is equipped with a first fine movement stage position measurement system  110 A that includes a first back side encoder system  70 A having a measurement arm  71 A which is supported substantially in a cantilevered state (supported near an edge) via a support member  72 A from main frame BD, and a first top side encoder system  80 A (not shown in  FIG. 1 , refer to  FIG. 6  and the like) to be described later on. However, the first fine movement stage position measurement system  110 A will be described after the description of the fine movement stage which will be described later on, for the sake of convenience. 
     Measurement section  300  is equipped with an alignment detection system ALG provided at main frame BD, a focal point position detection system (hereinafter, shortly referred to as an AF system) ( 90   a ,  90   b ) (not shown in  FIG. 1 , refer to  FIG. 6  and the like) provided at main frame BD, and a second fine movement stage position measurement system  110 B that includes a second back side encoder system  70 B having a measurement arm  71 B which is supported substantially in a cantilevered state (supported near an edge) via a support member  72 B from main frame BD, and a second top side encoder system  80 B (not shown in  FIG. 1 , refer to  FIG. 6  and the like) to be described later on. Incidentally, the second fine movement stage position measurement system  110 B will be described after the description of the fine movement stage which will be described later on, for the sake of convenience. Further, alignment detection system ALG is also called a mark detection system, an alignment device or the like. 
     As shown in  FIGS. 2, 5  and the like, alignment detection system ALG is placed in a state where its detection center is located at a position a predetermined distance away to the −Y side from optical axis AX, on a straight line (hereinafter referred to as a reference axis) LV which passes through the center of projection unit PU (optical axis AX of projection optical system PL, also coinciding with the center of exposure area IA previously described in the present embodiment) and is also parallel to the Y-axis. As alignment detection system ALG, for example, an FIA (Field Image Alignment) system is used that employs an image processing method of irradiating a broadband detection beam which does not expose the resist on the wafer onto an object mark, imaging an image of the object mark formed on a light-receiving plane by the reflection light from the object mark and an image of an index (an index pattern on an index plate provided within alignment detection system ALG) not shown using an imaging device (such as a CCD), and outputting the imaging signals. Imaging signals from alignment detection system ALG are supplied to main controller  20  (refer to  FIG. 6 ). Incidentally, as disclosed in, for example, US Patent Application Publication No. 2009/0233234, a plurality of mark detection systems whose detection areas are set at different positions in the X direction can be used as alignment detection system ALG. Further, the method of alignment detection system ALG is not limited to the imaging method, and for example, a method of irradiating a coherent measurement light on an alignment mark (diffraction grating) and detecting a diffraction light generated from the mark can also be employed. 
     As the AF system, as shown in  FIGS. 2 and 5 , a focal point position detection system employing an oblique-incidence method and made up of a light-transmitting system  90   a  and a light-receiving system  90   b  is used. A structure of a focal point position detection system (focal point position detection mechanism) similar to the AF system ( 90   a ,  90   b ) is disclosed in, for example, the third embedment of U.S. Pat. No. 4,558,949. This AF system ( 90   a ,  90   b ) obtains a position of a surface subject to detection in a direction of optical axis AX of projection optical system PL (that is, a defocus amount from the best image-forming plane). In the present embodiment, as an example, light-transmitting system  90   a  and light-receiving system  90   b  are placed symmetric with respect to reference axis LV, on a straight line (reference axis) LA that passes through the detection center of alignment detection system ALG and is parallel to the X-axis. The interval in the X-axis direction between light-transmitting system  90   a  and light-receiving system  90   b  is set smaller than a diameter of wafer W. 
     An irradiation point of a detection beam from the AF system ( 90   a ,  90   b ), that is, a detection point of the AF system ( 90   a ,  90   b ) coincides with an irradiation point of a detection beam from alignment detections system ALG, that is, the detection center of alignment detection system ALG. Therefore, in the present embodiment, the detection operations by the AF system ( 90   a ,  90   b ) and alignment detection system ALG can be concurrently performed. Incidentally, instead of the AF system ( 90   a ,  90   b ), a multi-point focal point position detection system disclosed in, for example, U.S. Pat. No. 5,448,332 and the like may be used. In the case of using the multi-point focal point position detection system, a plurality of detection points of the system are placed, for example, at a predetermined interval within the same range as the size of a shot area in the X-axis direction on the surface subject to detection. In the present embodiment, of the plurality of detection points, a detection point placed in the center in the X-axis direction is placed at substantially the same position as the detection center of alignment detection system ALG. 
     As it can be seen from  FIGS. 1, 3B  and the like, each of wafer stages WST 1  and WST 2  has a coarse movement stage WCS, and fine movement stage WFS which is supported in a non-contact state by coarse movement stage WCS via an actuator (for example, including at least one of a voice coil motor and an EI core) and can relatively move with respect to coarse movement stage WCS. Here, wafer stages WST 1  and WST 2  (coarse movement stages WCS) are respectively driven with predetermined strokes in the X-axis and the Y-axis directions, and also finely driven in the θz direction by coarse movement stage driving systems  51 A and  51 B (refer to  FIG. 6 ) each including a planar motor to be described later on. Further, fine movement stages WFS, which wafer stages WST 1  and WST 2  are respectively equipped with, are respectively driven in directions of six degrees of freedom (in each of the X-axis, the Y-axis, the Z-axis, the θx, the θy, and the θz directions) by fine movement stage driving systems  52 A and  52 B (refer to  FIG. 6 ) each including the actuator described previously, with respect to coarse movement stages WCS. Incidentally, coarse movement stage WCS may be driven in the directions of six degrees of freedom by a planar motor to be described later on. 
     Position information in the directions of six degrees of freedom of fine movement stage WFS supported by coarse movement stage WCS equipped in wafer stage WST 1  or WST 2  located in exposure station  200  is measured by the first fine movement stage position measurement system  110 A (refer to  FIGS. 1 and 6 ). 
     Further, position information in the directions of six degrees of freedom of fine movement stage WFS supported by coarse movement stage WCS equipped in wafer stage WST 2  or WST 1  located in measurement station  300  is measured by the second fine movement stage position measurement system  110 B (refer to  FIGS. 1 and 6 ). 
     Furthermore, position information of wafer stage WST 1  or WST 2  between exposure station  200  and measurement station  300 , that is, between the measurement range of the first fine movement stage position measurement system  110 A and the measurement range of the second fine movement stage position measurement system  110 B, is measured by a measurement system  80 D (refer to  FIG. 6 ) to be described later on. 
     Further, position information of measurement stage MST within the XY-plane is measured by a measurement table position measurement system  16  (refer to  FIG. 6 ) to be described later on. 
     Measurement values (position information) of the first fine movement stage position measurement system  110 A, the second fine movement stage position measurement system  110 B and measurement system  80 D are supplied to main controller  20  (refer to  FIG. 6 ), each for position control of wafer stages WST 1  and WST 2 . Especially, the measurement values of the first fine movement stage position measurement system  110 A and the second fine movement stage position measurement system  110 B are used in position control of fine movement stage WFS of each of wafer stages WST 1  and WST 2 . Further, measurement values of measurement table position measurement system  16  are supplied to main controller  20 , for position control of measurement table MTB (refer to  FIG. 6 ). 
     Now, details of the structure and the like of the stage systems will be described. First of all, wafer stages WST 1  and WST 2  will be described. As can be seen from  FIGS. 1 and 2 , wafer stages WST 1  and WST 2  are similarly structured though they are bilaterally symmetric, and therefore, wafer stage WST 1  is representatively focused on and described here. 
     Coarse movement stage WCS equipped in wafer stage WST 1 , as shown in  FIG. 3B , is equipped with a coarse movement slider section  91 , a pair of side wall sections  92   a  and  92   b , and a pair of stator sections  93   a  and  93   b . Coarse movement slider section  91  is made up of a member having a rectangular plate shape whose length in the X-axis direction in a planar view (when viewing from the +Z direction) is slightly longer than the length in the Y-axis direction. The pair of side wall sections  92   a  and  92   b  are each made up of a rectangular plate shaped member whose longitudinal direction is in the Y-axis direction, and are fixed to the upper surfaces on one end and the other end, respectively, in the longitudinal direction of coarse movement slider section  91  in a state parallel to a YZ-plane. The pair of stator sections  93   a  and  93   b  are fixed facing inward in the center along the Y-axis direction on the upper surfaces of side wall sections  92   a  and  92   b , respectively. Coarse movement stage WCS, as a whole, has a short rectangular parallelepiped shape with an opening in the center of the X-axis direction on the upper surface and in both side surfaces in the Y-axis direction. That is, in coarse movement stage WCS, a space is formed inside penetrated in the Y-axis direction. Measurement arms  71 A and  71 B are inserted into this space, at the time of exposure, the time of alignment and the like which will be described later on. Incidentally, the length in the Y-axis direction of side wall sections  92   a  and  92   b  can be substantially the same as that of stator sections  93   a  and  93   b . That is, side wall sections  92   a  and  92   b  can be provided only in the center along the Y-axis direction on the upper surface of one end and the other end in the longitudinal direction of coarse movement slider section  91 . Further, coarse movement stage WCS should be movable supporting fine movement stage WFS, and can be called a main section, or movable body, a moving body or the like of wafer stage WST 1 . 
     Inside base board  12 , as shown in  FIG. 1 , a coil unit is housed that includes a plurality of coils  17  which are placed in the shape of a matrix with the XY two-dimensional directions serving as a row direction and a column direction. Incidentally, base board  12  is placed below projection optical system PL so that the surface of based board  12  is substantially parallel to the XY plane. 
     Corresponding to the coil unit, on the bottom surface of coarse movement stage WCS, or in other words, on the bottom surface of coarse movement slider section  91 , as shown in  FIG. 3B , a magnet unit is provided, made up of a plurality of permanent magnets  18  placed in the shape of a matrix with the XY two-dimensional directions serving as a row direction and a column direction. The magnet units, along with the coil units of base board  12 , structure coarse movement stage driving system  51 A (refer to  FIG. 6 ) made up of an electromagnetically (Lorentz force) driven planar motor like the ones disclosed in, for example, U.S. Pat. No. 5,196,745 and the like. The magnitude and the direction of current supplied to each coil  17  structuring the coil unit are controlled by main controller  20 . 
     On the bottom surface of coarse movement slider section  91  in the periphery of the magnet unit described above, a plurality of air bearings  94  are fixed. Coarse movement stage WCS is supported by levitation above base board  12  by the plurality of air bearings  94  via a predetermined clearance gap (clearance, gap), for example, a clearance gap of around several μm, and is driven by coarse movement stage driving system  51 A in the X-axis direction, the Y-axis direction, and the θz direction. 
     Incidentally, coarse movement stage driving system  51 A is not limited to the electromagnetically (Lorentz force) driven planar motor, and for example, a planar motor which employs a variable reluctance drive method can also be used. Besides this, it is also possible that coarse movement stage driving system  51 A is structured using a magnetically levitated type planar motor, and with the planar motor, coarse movement stage WCS can be driven in the directions of six degrees of freedom. In this case, air bearings do not have to be provided on the bottom surface of coarse movement slider section  91 . 
     The pair of stator sections  93   a  and  93   b  are each made of a member whose external shape is a plate, and coil units CUa and CUb made up of a plurality of coils used to drive fine movement stage WFS are housed inside, respectively. The magnitude and the direction of current supplied to each coil structuring coil units CUa and CUb are controlled by main controller  20 . 
     Fine movement stage WFS, as shown in  FIG. 3B , is equipped with a main section  81 , a pair of mover sections  82   a  and  82   b  fixed to one edge and the other edge in the longitudinal direction of main section  81 , respectively, and wafer table WTB made up of a plate-shaped member having a rectangular shape in a planar view integrally fixed to the upper surface of main section  81 . 
     Main section  81  is made up of an octagonal plate-shaped member whose longitudinal direction is in the X-axis direction in a planar view. On the lower surface of main section  81 , a scale plate  83  made up of a plate-shaped member of a predetermined thickness and a predetermined shape, such as for example, a rectangular shape or an octagonal shape slightly larger than main section  81  in a planar view, is placed and fixed horizontally (parallel to the wafer W surface). In an area at least slightly larger than wafer W, on the lower surface of scale plate  83 , a two-dimensional grating (hereinafter, simply referred to as a grating) RG is provided. Grating RG includes a reflection type diffraction grating (X diffraction grating) whose period direction is in the X-axis direction and a reflection type diffraction grating (Y diffraction grating) whose period direction is in the Y-axis direction. The pitch of the grid lines of the X diffraction grating and the Y diffraction grating is set, for example, to 1 μm. 
     Main section  81  and scale plate  83  are preferably formed of, for example, a material having a thermal expansion coefficient which is the same or about the same, and the material preferably has a low thermal expansion coefficient. Further, the surface of grating RG can be protected, being covered by a protective member, such as, for example, a cover glass which is made of a transparent material having transmittance to light and a low thermal expansion coefficient. Incidentally, grating RG can employ any structure and the like as long as the grating is arrayed periodically in two different directions, and the period directions do not necessarily have to coincide with the X and the Y directions, and for example, can be rotated by an angle of 45 degrees with respect to the X and the Y directions. 
     While, in the present embodiment, fine movement stage WFS has main section  81  and wafer table WTB, wafer table WTB can be, for example, driven by the actuator described previously without providing main section  81 . Further, fine movement stage WFS should have a mounting area for wafer W at a part of its upper surface, and can be called a holding section, or a table, a movable section or the like of wafer stage WST 1 . 
     The pair of mover sections  82   a  and  82   b  have housings whose YZ sections are rectangular frame shaped fixed to one end surface and the other end surface in the X-axis direction of main section  81 , respectively. Hereinafter, for the sake of convenience, these housings will be expressed as housings  82   a  and  82   b , using the same reference signs as mover sections  82   a  and  82   b.    
     Housing  82   a  has a space (opening section) having a rectangular YZ sectional shape elongated in the Y-axis direction and whose size (length) in the Y-axis direction and size (height) in the Z-axis direction are both slightly larger than those of stator section  93   a . Into the space of housing  82   a , the edge on the −X side of stator section  93   a  of coarse movement stage WCS is inserted in a non-contact manner. Inside an upper wall section  82   a   1  and a bottom wall section  82   a   2  of housing  82   a , magnet units MUa 1  and MUa 2  are provided. 
     Mover section  82   b  is similarly structured to mover section  82   a , while being bilaterally symmetric. Into the space of housing (mover section)  82   b , the edge on the +X side of stator section  93   b  of coarse movement stage WCS is inserted in a non-contact manner. Inside an upper wall section  82   b   1  and a bottom wall section  82   b   2  of housing  82   b , magnet units MUb 1  and MUb 2  which are structured similar to magnet units MUa 1  and MUa 2  are provided. 
     Coil units CUa and CUb described above are housed inside stator sections  93   a  and  93   b , respectively, corresponding to magnet units MUa 1  and MUa 2 , and MUb 1  and MUb 2 , respectively. 
     The structures of magnet units MUa 1  and MUa 2 , and MUb 1  and MUb 2 , and coil units CUa and CUb are disclosed in detail in, for example, U.S. Patent Application Publication No. 2010/0073652, U.S. Patent Application Publication No. 2010/0073653 and the like. 
     In the present embodiment, similarly to the U.S. Patent Application Publication No. 2010/0073652 and U.S. Patent Application Publication No. 2010/0073653 described above, fine movement stage driving system  52 A (refer to  FIG. 6 ), which supports fine movement stage WFS by levitation with respect to coarse movement stage WCS in a non-contact state and also drives fine movement stage WFS in the directions of six degrees of freedom in a non-contact manner, is structured including the pair of magnet units MUa 1  and MUa 2  which mover section  82   a  has and coil unit CUa which stator section  93   a  has, and the pair of magnet units MUb 1  and MUb 2  which mover section  82   b  has and coil unit CUb which stator section  93   b  has that are previously described. 
     Incidentally, in the case of using a magnetic levitation type planar motor as coarse movement stage driving system  51 A (refer to  FIG. 6 ), because fine movement stage WFS can be finely driven in each of the Z-axis, the θx, and the θy directions integrally with coarse movement stage WCS by the planar motor, fine movement stage driving system  52 A can employ a structure where fine movement stage WFS is drivable in each of the X-axis, the Y-axis, and the θz directions, that is, in directions of three degrees of freedom within the XY-plane. Besides this, for example, to each of the pair of side wall sections  92   a  and  92   b  of coarse movement stage WCS, a pair of electromagnets can be provided, each facing the oblique side section of the octagonal shape of fine movement stage WFS, and at fine movement stage WFS, a magnetic body member can be provided facing each electromagnet. Because this allows fine movement stage WFS to be driven within the XY-plane by the magnetic force of the electromagnets, mover sections  82   a  and  82   b  and stator sections  93   a  and  93   b  can structure a pair of Y-axis linear motors. 
     In the center of the upper surface of wafer table WTB, a wafer holder (not shown) is provided which holds wafer W by vacuum chucking and the like. The wafer holder can be integrally formed with wafer table WTB, or can be fixed to wafer table WTB, for example, via an electrostatic chuck mechanism, a clamp mechanism or the like, or by adhesion and the like. Here, although omitted in the drawings, in main section  81 , a vertical movement pin which can move vertically is provided via a hole provided in the wafer holder. This vertical movement pin can move vertically between a first position where its upper surface is positioned above the upper surface of the wafer holder and a second position where its upper surface is positioned below the upper surface of the wafer holder. 
     Outside the wafer holder (mounting area of the wafer) on the upper surface of wafer table WTB, as shown in  FIG. 3A , a circular opening slightly larger than the wafer holder is formed in the center, and a plate (liquid repellent plate)  28  is provided that has a rectangular outer shape (outline). Plate  28  is made of a material with a low thermal expansion coefficient, such as, for example, glass or ceramics (e.g., Zerodur (product name) of Schott AG, Al 2 O 3  or TiC or the like), and on its surface, a liquid repellent processing to liquid Lq is applied. To be specific, a liquid repellent film is formed of, for example, a fluorine-based resin material such as a fluororesin material or polytetrafluoroethylene (Teflon (registered trademark)), an acrylic-based resin material, a silicon-based resin material or the like. Incidentally, plate  28  is fixed to the upper surface of wafer table WTB so that its entire surface (or a part of the surface) is substantially flush with the surface of wafer W. 
     Plate  28  is positioned in the center in the X-axis direction of wafer table WTB, and has a first liquid repellent area  28   a  having a rectangular outer shape (outline) and a circular opening formed in the center, and a pair of second liquid repellent areas  28   b  having a rectangular shape and being positioned on the +X side edge and the −X side edge of wafer table WTB, with the first liquid repellent area  28   a  in between in the X-axis direction. Incidentally, in the present embodiment, because water is used as liquid Lq as is previously described, hereinafter, the first liquid repellent area  28   a  and the second liquid repellent area  28   b  will also be referred to as a first water repellent plate  28   a  and a second water repellent plate  28   b , respectively. 
     In the vicinity of the edge on the +Y side of the first water repellent plate  28   a , a measurement plate  30  is provided. In this measurement plate  30 , a fiducial mark FM is provided in the center, and a pair of aerial image measurement slit patterns (slit shaped measurement patterns) SL are provided, with fiducial mark FM in between. And, corresponding to each aerial image measurement slit pattern SL, a light-transmitting system (not shown) is provided which guides illumination light IL passing through the slit patterns to the outside of wafer stage WST (a light-receiving system provided at measurement stage MST to be described later on). Further, on the upper surface of measurement plate  30 , a reflection surface to reflect the detection beam from the AF system ( 90   a ,  90 B) described previously is formed at least in the center area (or the entire area). Measurement plate  30  is, for example, placed in an opening of plate  28 , which is different from the opening where the wafer holder is placed, and a gap between measurement plate  30  and plate  28  is covered by a seal member or the like so as to prevent the liquid from flowing into wafer table WTB. Further, measurement plate  30  is provided at wafer table WTB so that the surface of measurement plate  30  is substantially flush with the surface of plate  28 . Incidentally, it is also possible that at least one opening section (light-transmitting section) different from slit patterns SL is formed at measurement plate  30 , and illumination light IL transmitted through the opening section via projection optical system PL and the liquid is detected by a sensor, and thereby, for example, optical characteristics (including wavefront aberration and the like) of projection optical system PL and/or characteristics of illumination light IL (including a light quantity, and illuminance distribution within exposure area IA described previously, and the like), and the like are measurable. 
     On the pair of the second water repellent plates  28   b , scales  39   1  and  39   2  are respectively formed, for the first and the second top side encoder systems  80 A and  80 B. To describe this in detail, scales  39   1  and  39   2  are each structured by a reflection type two-dimensional diffraction grating which is a combination of, for example, a diffraction grating whose period direction is in the Y-axis direction and a diffraction grating whose period direction is in the X-axis direction. The pitch of the grid lines of the two-dimensional diffraction grating is set to, for example, 1 μm for both the Y-axis direction and the X-axis direction. Further, because the pair of the second water repellent plates  28   b  respectively have scales (two-dimensional gratings)  39   1  and  39   2 , the pair of the second water repellent plates  28   b  are each called a grating member, a scale plate, or a grid plate or the like, and in the present embodiment, for example, a two-dimensional grating is formed on a glass plate surface having a low thermal expansion coefficient and a liquid-repellent film is formed so as to cover the two-dimensional grating. Incidentally, in  FIG. 3A , for the sake of convenience in the drawings, the pitch of the grating is illustrated larger than the actual pitch. Further, the two-dimensional grating can employ any structure and the like as long as the two-dimensional grating is arrayed periodically in two different directions, and the period directions do not necessarily have to coincide with the X and the Y directions, and for example, can be rotated by an angle of 45 degrees with respect to the X and the Y directions. 
     Further, at predetermined positions on edge portions of scales  39   1  and  39   2 , marks are respectively formed, though not shown, which are subject to imaging of a pair of imaging sensors of an exposure coordinate return position measurement system to be described later on, when wafer table WTB 1  is positioned at a predetermined position (scrum starting position to be described later on). 
     Incidentally, to protect the diffraction gratings of the pair of the second water repellent plates  28   b  and the like, it is also effective to cover the diffraction gratings with a low thermal expansion coefficient glass plate that has water repellency. Here, as the glass plate, a plate whose thickness is around the same as the wafer, such as for example, a plate having a 1 mm thickness, can be used, and, as an example, the plate is installed on the upper surface of wafer table WTB so that the surface of the glass plate is at substantially the same height as (flush with) the wafer surface. Further, in the case when the pair of the second water repellent plates  28   b  are placed at such a distance away from wafer W that the second water repellent plates  28   b  do not come into contact with the liquid of the liquid immersion area described previously at least during the exposure operation of wafer W, the surfaces of the pair of the second water repellent plates  28   b  do not necessarily have to be liquid-repellent. In other words, the pair of the second water repellent plates  28   b  can each be a simple grating member where a scale (two-dimensional grating) is formed. 
     While, in the present embodiment, plate  28  is provided at wafer table WTB, plate  28  needs not be provided. In this case, on the upper surface of wafer table WTB, a recessed section where the wafer holder is placed is provided, and for example, a pair of the grating members whose surfaces are not liquid-repellent described previously can be placed with the recessed section in between in the X direction on wafer table WTB. As previously described, this pair of grating members should be placed such a distance away from the recessed section that the grating members do not come into contact with the liquid of the liquid immersion area. Further, the recessed section can be formed so that the surface of wafer W held by the wafer holder in the recessed section is substantially flush with the upper surface of wafer table WTB. Incidentally, the entire area or a partial area (including at least a periphery area surrounding the recessed section) of the surface of the upper surface of wafer table WTB can be liquid-repellent. Further, in the case when the pair of grating members where scales (two-dimensional gratings)  39   1  and  39   2  are formed are placed in proximity to the recessed section, the pair of the second water repellent plates  28   b  described previously can be used instead of the pair of the grating members whose surfaces are not liquid-repellent. 
     Incidentally, near the edge of the scale of each of the second water repellent plates  28   b , positioning patterns not shown are each provided, which are used to decide a relative position between an encoder head to be described later on and the scale. This positioning pattern is structured, for example, of grid lines with different reflectivity, and when the encoder head scans this positioning pattern, the intensity of the output signal of the encoder changes. Therefore, a threshold value is decided in advance, and the position where the intensity of the output signal exceeds the threshold value is detected. The relative position between the encoder head and the scale is set with the detected position serving as a reference. 
     To coarse movement stage WCS of wafer stage WST 1 , as shown in  FIG. 2 , one end of a tube  22 A with which piping and wiring are integrated is connected, and the other end of tube  22 A is connected to a tube carrier TC 1 . Tube carrier TC 1  is used to supply power usage such as electric power (electric current), cooling medium, compressed air, vacuum and the like to wafer stage WST 1  (coarse movement stage WCS) via tube  22 A. Further, a part of the power usage supplied to coarse movement stage WCS (for example, vacuum and the like) is supplied to fine movement stage WFS. Tube carrier TC 1  is driven in the Y-axis direction by a carrier driving system  24 A (refer to  FIG. 6 ) composed of, for example, a linear motor. In this case, a stator of carrier driving system  24 A may be arranged integrally with a part of the −X edge of base board  12  as shown in  FIG. 2 , or may be installed on the −X side of base board  12  separately from base board  12  with the Y-axis direction serving as a longitudinal direction so as to reduce the influence of a reaction force generated by the drive of tube carrier TC 1  put on wafer stage WST 1 . Further, the tube carrier can be placed on base board  12 , and in this case, the tube carrier can be driven by a planar motor, which will be described later on, that drives coarse movement stage WCS. Incidentally, the tube carrier can also be called a cable carrier or a follower. Further, wafer stage WST 1  does not necessarily have to employ a coarse-fine movement structure. 
     Although tube carrier TC 1  is driven in the Y-axis direction following wafer stage WST 1  via carrier driving system  24 A by main controller  20 , drive of tube carrier TC 1  in the Y-axis direction does not necessarily have to strictly follow the drive of wafer stage WST 1  in the Y-axis direction, and only has to follow the drive within a certain permissible range. 
     Wafer stage WST 2  is similarly structured, though wafer stage WST 2  is bilaterally symmetric with wafer stage WST 1  described above. Accordingly, wafer stage WST 2  (coarse movement stage WCS) is driven in the X-axis direction, the Y-axis direction and the θz direction by coarse movement stage driving system  51 B (refer to  FIG. 6 ) composed of a planar motor that is structured similar to coarse movement stage driving system  51 A. Further, fine movement stage WFS is supported in a non-contact state by coarse movement stage WCS that wafer stage WST 2  is equipped with, and is also driven in the directions of six degrees of freedom in a non-contact manner by fine movement stage driving system  52 B (refer to  FIG. 6 ) that is structured similar to fine movement stage driving system  52 A. Further, as shown in  FIG. 2 , to wafer stage WST 2 , a tube carrier TC 2  is connected via a tube  22 B, and tube carrier TC 2  is driven in the Y-axis direction following wafer stage WST 2  by main controller  20  via a carrier driving system  24 B (refer to  FIG. 6 ) composed of a linear motor. 
     Further, as described above, in the present embodiment, because fine movement stage WFS that constitutes each of wafer stages WST 1  and WST 2  is equipped with wafer table WTB, hereinafter, for the sake of convenience, fine movement stage WFS including wafer table WTB that constitutes wafer stage WST 1  will also be expressed as a wafer table WTB 1 , and fine movement stage WFS including wafer table WTB that constitutes wafer stage WST 2  will also be expressed as a wafer table WTB 2  (refer to, for example,  FIGS. 1, 2  and the like). Further, wafer tables WTB 1  and WTB 2  are also collectively referred to as wafer table WTB when appropriate. 
     Next, measurement stage MST will be described.  FIGS. 4A and 4B  show a front view (a view when viewed from the −Y direction), and a plan view (a view when viewed from +Z direction) of measurement stage MST, respectively. As shown in these  FIGS. 4A and 4B , measurement stage MST is equipped with a slider section  60 , a support section  62  and a measurement table MTB. Slider section  60  is composed of a member having a rectangular shape with the X-axis direction serving as longitudinal direction in a planar view (when viewed from the +Z direction). Support section  62  is composed of a rectangular parallelepiped member and is fixed to the end on the −X side of the upper surface of slider section  60 . Measurement table MTB is composed of a member having a rectangular plate shape and is supported in a cantilevered manner on support section  62 , and is finely driven, for example, in the directions of six degrees of freedom (or directions of three degrees of freedom within the XY-plane), via a measurement table driving system  52 C (refer to  FIG. 6 ). 
     On the bottom surface of slider section  60 , although not shown, a magnet unit made up of a plurality of permanent magnets is provided that structures, along with a coil unit (coils  17 ) of base board  12 , a measurement stage driving system  51 C (refer to  FIG. 6 ) made up of an electromagnetically (Lorentz force) driven planar motor. On the bottom surface of slider section  60 , in the periphery of the magnet unit described above, a plurality of air bearings (not shown) are fixed. Measurement stage MST is supported by levitation above base board  12  by the air bearings previously described via a predetermined clearance gap (gap, clearance), such as for example, a clearance gap of around several μm, and is driven in the X-axis direction and the Y-axis direction by measurement stage driving system  51 C. Incidentally, while measurement stage MST employs an air levitation method, measurement stage MST can employ, for example, a magnetic levitation method by a planar motor. 
     At measurement table MTB, various measurement members are provided at the −X side half of a portion that excludes a band-shaped section of the edge on the −Y side (hereinafter, which is also referred to as a delivery section as needed). As such measurement members, for example, as shown in  FIG. 4B , an illuminance irregularity sensor  95  which has a pin-hole shaped light-receiving section that receives illumination light IL on an image plane of projection optical system PL, an aerial image measuring device  96  which measures an aerial image (projection image) of a pattern projected by projection optical system PL, a wavefront aberration measuring device  97  which employs a Shack-Hartmann method which is disclosed in, for example, PCT International Publication No. 03/065428 and the like, an illuminance monitor  98  which has a light-receiving section of a predetermined area that receives illumination light IL on an image plane of projection optical system PL, and the like are provided. 
     As illuminance irregularity sensor  95 , a sensor having a structure similar to the one disclosed in, for example, U.S. Pat. No. 4,465,368 and the like can be used. Further, as aerial image measuring device  96 , a device having a structure similar to the one disclosed in, for example, U.S. Patent Application Publication No. 2002/0041377 and the like can be used. As wavefront aberration measuring device  97 , the one disclosed in, for example, PCT International Publication No. 99/60361 (corresponding European Patent No. 1079223) can be used. As illuminance monitor  98 , a monitor having a structure similar to the one disclosed in, for example, U.S. Patent Application Publication No. 2002/0061469 and the like can be used. 
     Further, at measurement table MTB, a pair of light-receiving systems (not shown) are provided at the delivery section in a placement that can face the pair of light-transmitting systems (not shown) previously described. In the present embodiment, aerial image measurement devices  45   1  and  45   2  (refer to  FIG. 6 ) are structured in which each light-transmitting system (not shown) guides illumination light IL having passed through each aerial image measurement slit pattern SL of measurement plate  30  on wafer stage WST 1  or WST 2 , and a photodetection element of each light-receiving system (not shown) within measurement stage MST receives the light, in a state where wafer stage WST 1  or WST 2  and measurement stage MST are close to each other within a predetermined distance in the Y-axis direction (including a state in contact). 
     Incidentally, while, in the present embodiment, the four measurement members ( 95 ,  96 ,  97  and  98 ) are provided on measurement table MTB, the type and/or the number of the measurement members are/is not limited to those described above. As the measurement members, for example, a transmittance measuring device that measures the transmittance of projection optical system PL, and/or a measuring device which observes local liquid immersion device  8  previously described, such as for example, nozzle unit  32  (or tip lens  191 ) and the like, can also be used. Furthermore, a member different from the measurement members, such as, for example, a cleaning member that cleans nozzle unit  32 , tip lens  191  and the like can also be installed at measurement stage MST. 
     Incidentally, in the present embodiment, corresponding to performing the liquid immersion exposure of wafer W by exposure light (illumination light) IL via projection optical system PL and liquid (water) Lq, illumination light IL is to be received via projection optical system PL and the water, in illuminance irregularity sensor  95 , aerial image measuring device  96 , wavefront aberration measuring device  97  and illuminance monitor  98  described above used in measurement using illumination light IL. Further, out of each sensor, only a part of the sensor, such as for example, a light-receiving plane (light-receiving section) which receives illumination light IL via an optical system and water and a part of the optical system can be placed at measurement table MTB, or the whole sensor can be placed at measurement table MTB. 
     At the −X side half of a portion excluding the delivery section of measurement table MTB, a two-dimensional grating  69  having period directions in the X-axis direction and the Y-axis direction is provided. On the upper surface of measurement table MTB, a plate  63  is fixed, made up of a transparent member whose surface is covered with a liquid repellent film (water repellent film), in a state covering two-dimensional grating  69  and various measurement members. Plate  63  is made of a material similar to plate  28  previously described. On the lower surface (surface on the −Z side) of measurement table MTB, a grating RGa similar to grating RG previously described is provided. 
     Incidentally, in the case when measurement stage driving system  51 C is structured using a magnetic levitation type planar motor, the measurement stage can be, for example, a stand-alone stage which is movable in the directions of six degrees of freedom. Further, plate  63  does not necessarily have to be provided at measurement table MTB. In this case, on the upper surface of measurement table MTB, a plurality of openings where the light-receiving planes (light-transmitting sections) of the plurality of sensors described previously are respectively placed are formed, and for example, at least a part of the sensor including the light-receiving plane should be provided at measurement table MTB so that the light-receiving plane in the opening is substantially flush with the upper surface of measurement table MTB. 
     Measurement stage MST is engageable with measurement arm  71 A from the −X side, and in the engaged state, measurement table MTB is positioned right above measurement arm  71 A. At this point in time, position information of measurement table MTB in the directions of six degrees of freedom is measured by a plurality of encoder heads to be described later that irradiate a measurement beam on grating RGa that measurement arm  71 A has. 
     Further, measurement table MTB can be as close as a distance of, for example, around 300 μm or less, or be in contact from the +Y side to/with fine movement stage WFS (wafer table WTB 1  or WTB 2 ) supported by coarse movement stage WCS, and in such a proximity or contact state, forms a surface (for example, refer to  FIG. 10 ) that appears to be completely flat, along with the upper surface of wafer table WTB 1  or WTB 2 . Measurement table MTB (measurement stage MST) is driven by main controller  20  via measurement stage driving system  51 C, and receives/delivers a liquid immersion area (liquid Lq) from/to measurement table MTB and wafer table WTB 1  or WTB 2 . That is, a part of a boundary that defines the liquid area formed under projection optical system PL is replaced from one of the upper surface of the wafer table (WTB 1  or WTB 2 ) and the upper surface of measurement table MTB to the other. Incidentally, the delivery of the liquid immersion area (liquid Lq) between measurement table MTB and wafer table WTB 1  or WTB 2  will be further described later on. 
     Next, the structure of the first fine movement stage position measurement system  110 A (refer to  FIG. 6 ), which is used to measure position information of fine movement stage WFS (wafer table WTB 1  or WTB 2 ) held movable by coarse movement stage WCS that is equipped in wafer stage WST 1  or WST 2  located at exposure station  200 , will be described. Here, the first fine movement stage position measurement system  110 A will be described, by describing, as an example, the case of measuring position information of wafer table WTB 1  that wafer stage WST 1  is equipped with. 
     The first back side encoder system  70 A of the first fine movement stage position measurement system  110 A, as shown in  FIG. 1 , is equipped with measurement arm  71 A which is inserted into a space provided inside coarse movement stage WCS in a state where wafer stage WST 1  is placed below projection optical system PL. 
     Measurement arm  71 A, as is shown in  FIG. 1 , has an arm member  71   1  supported by main frame BD in a cantilevered state via support member  72 A, and an encoder head (at least a part of the optical system) to be described later on placed inside arm member  71   1 . That is, in order to place a head section (including at least a part of the optical system) of the first back side encoder system  70 A at a position lower than grating RG of wafer table WTB 1 , the head section is supported by a measurement member (which is also called a support member or a metrology arm) including arm member  71   1  of measurement arm  71 A and support member  72 A. With this placement, a measurement beam of the first back side encoder system  70 A is irradiated on grating RG from below. Arm member  71   1  is made up of a hollow columnar member having a rectangular cross section whose longitudinal direction is in the Y-axis direction. The size in the width direction (the X-axis direction) of arm member  71   1  is, for example as shown in  FIG. 2 , widest near the base end, and the width narrows gradually from the base end toward the tip end side to a position being slightly near to the base end from the center in the longitudinal direction, and the width is substantially constant from the position slightly near to the base end from the center in the longitudinal direction to the tip end. While, in the present embodiment, the head section of the first back side encoder system  70 A is placed between grating RG of wafer table WTB 1  and the surface of base board  12 , the head section can be placed, for example, below base board  12 . 
     Arm member  71   1  is made of a material having a low thermal expansion coefficient, preferably a material of zero expansion (for example, Zerodur (product name) of Schott AG and the like). Arm member  71   1  has high rigidity because of being hollow and having a wide base end, and because the shape in a planar view is set in the manner described above, in a state where wafer stage WST 1  is placed below projection optical system PL, wafer stage WST 1  moves in a state where the tip of arm member  71   1  is inserted into the space of coarse movement stage WCS, and on this movement, this structure can keep arm member  71   1  from interfering the movement of wafer stage WST 1 . Further, an optical fiber of a light-transmitting side (light source side) and a light-receiving side (detector side) and the like, which are used for transmitting light (measurement beam) to/from an encoder head to be described later on, run through inside the hollow section of arm member  71   1 . Incidentally, arm member  71   1  can be formed of, for example, a member having a portion where only the optical fiber and the like run through is hollow, and other portions being solid. Incidentally, in order to reduce the vibration of a particular frequency of arm member  71   1 , a mass damper (also called a dynamic mass damper) having a specific frequency as a particular resonance frequency may provided at the tip of arm member  71   1 . Incidentally, the vibration of arm member  71   1  can also be suppressed or prevented by other vibration suppressing members than the mass damper. Further, this vibration suppressing member is one of compensation devices that compensate for measurement errors of the first back side encoder system  70 A that occur due to the vibration of arm member  71   1 , and the first top side encoder system  80 A to be described later on is also one of the compensation devices. 
     In a state where wafer stage WST 1  is placed below projection optical system PL, the tip of arm member  71   1  of measurement arm  71 A is inserted into the space within coarse movement stage WCS, and as shown in  FIG. 1 , its upper surface faces grating RG (not shown in  FIG. 1 , refer to  FIG. 3B  and the like) provided on the lower surface of fine movement stage WFS (to be more precise, the lower surface of main section  81 ). The upper surface of arm member  71   1  is placed substantially parallel to the lower surface of fine movement stage WFS, in a state where a predetermined clearance gap (gap, clearance), for example, a clearance gap of around several mm, is formed between the upper surface of arm member  71   1  and the lower surface of fine movement stage WFS. Incidentally, a clearance gap between the upper surface of arm member  71   1  and the lower surface of fine movement stage WFS may be several mm or more or less. 
     The first back side encoder system  70 A, as shown in  FIG. 7 , includes a three-dimensional encoder  73   a  which measures a position, in the X-axis, the Y-axis and the Z-axis directions, of fine movement stage WFS located at exposure station  200 , an XZ encoder  73   b  which measures a position of fine movement stage WFS in the X-axis and the Z-axis directions, and a YZ encoder  73   c  which measures a position of fine movement stage WFS in the Y-axis and the Z-axis directions. 
     XZ encoder  73   b  and YZ encoder  73   c  are respectively equipped with a two-dimensional head whose measurement direction is in the X-axis and the Z-axis directions and a two-dimensional head whose measurement direction is in the Y-axis and the Z-axis directions, each housed inside arm member  71   1  of measurement arm  71 A. Hereinafter, for the sake of convenience, the two-dimensional heads that XZ encoder  73   b  and YZ encoder  73   d  are respectively equipped with will be expressed as an XZ head  73   b  and a YZ head  73   c , using the same reference signs as the respective encoders. As each of such XZ head  73   b  and YZ head  73   c , an encoder head (hereinafter, shortly referred to as a head as needed) having a structure similar to the displacement measurement sensor head disclosed in, for example, U.S. Pat. No. 7,561,280, can be used. Further, three-dimensional encoder  73   a  is equipped with a three-dimensional head whose measurement direction is in the X-axis, the Y-axis, and the Z-axis directions, housed inside arm member  71   1  of measurement arm  71 A. Hereinafter, for the sake of convenience, the three-dimensional head that three-dimensional encoder  73   a  is equipped with will be expressed as a three-dimensional head  73   a , using the same reference sign of the encoder. As three-dimensional head  73   a , for example, a three-dimensional head which is structured combining XZ head  73   b  and YZ head  73   c  so that the measurement points (detection points) of both the heads are at the same point and measurement in the X-axis direction, the Y-axis direction and the Z-axis direction is also possible, can be used. 
       FIG. 8A  shows the tip of arm member  71   1  in a perspective view, and  FIG. 8B  shows a plan view of the upper surface of the tip of arm member  71   1  when viewed from the +Z direction. As shown in  FIGS. 8A and 8B , three-dimensional head  73   a  irradiates measurement beams LBxa 1  and LBxa 2  (refer to  FIG. 8A ) on grating RG from two points (refer to the white circles in  FIG. 8B ) which are on a straight line LX 1  parallel to the X-axis, at positions of an equal distance (referred to as a distance “a”) from a straight line LY 1  parallel to the Y-axis that is a predetermined distance away from center line CL. Further, three-dimensional head  73   a  irradiates measurement beams LBya 1  and LBya 2  on grating RG from two points that are at positions on straight line LY 1  and of distance “a” from straight line LX 1 . Measurement beams LBxa 1  and LBxa 2  are irradiated on the same irradiation point on grating RG, and further, measurement beams LBya 1  and LBya 2  are also irradiated on that irradiation point. In the present embodiment, the irradiation point of measurement beams LBxa 1  and LBxa 2  and measurement beams LBya 1  and LBya 2 , or in other words, the detection point (refer to reference sign DP 1  in  FIG. 8B ) of three-dimensional head  73   a  is located directly under the exposure position which is the center of irradiation area (exposure area) IA of illumination light IL irradiated on wafer W (refer to  FIG. 1 ). Here, straight line LY 1  coincides with reference axis LV previously described. 
     XZ head  73   b  is placed at a position a predetermined distance away to the +Y side of three-dimensional head  73   a . XZ head  73   b , as shown in  FIG. 8B , irradiates measurement beams LBxc 1  and LBxc 2  each shown in a broken line in  FIG. 8A  on a common irradiation point on grating RG from two points (refer to the white circles in  FIG. 8B ) which are on a straight line LX 2  that is parallel to the X-axis and is positioned a predetermined distance to the +Y side of straight line LX 1 , at positions that are each away from straight line LY 1  by distance “a”. The irradiation point of measurement beams LBxc 1  and LBxc 2 , that is to say, the detection point of XZ head  73   b  is shown by reference sign DP 3  in  FIG. 8B . 
     YZ head  73   c  is placed at a position a predetermined distance away to the −X side of three-dimensional head  73   a . YZ head  73   c  irradiates measurement beams LByb 1  and LByb 2  on grating RG from two points (refer to the white circles in  FIG. 8B ) which are placed on straight line LY 2  which is symmetric to straight line LY 1  with respect to center line CL, at positions that are away from straight line LX 1  by distance “a”. Measurement beams LByb 1  and LByb 2  are irradiated on the same irradiation point on grating RG. The irradiation point of measurement beams LByb 1  and LByb 2 , that is to say, the detection point of YZ head  73   c  (refer to reference sign DP 2  in  FIG. 8B ) is a point a predetermined distance away to the −X side from a point directly under the exposure position. 
     In the first back side encoder system  70 A, the three-dimensional encoder is structured by three-dimensional head  73   a  which measures the position of fine movement stage WFS in the X-axis, the Y-axis, and the Z-axis directions using the X diffraction grating and the Y diffraction grating of grating RG, the XZ encoder is structured by XZ head  73   b  which measures the position of fine movement stage WFS in the X-axis and the Z-axis directions using the X diffraction grating of grating RG, and the YZ encoder is structured by YZ head  73   c  which measures the position of fine movement stage WFS in the Y-axis and the Z-axis directions using the Y diffraction grating of grating RG. Hereinafter, for the sake of convenience, the above-described encoders are respectively expressed as a three-dimensional encoder  73   a  (encoder  73   a ), an XZ encoder  73   b  (encoder  73   b ) and a YZ encoder  73   c  (encoder  73   c ), using the same reference signs as the respective heads. 
     The output of encoders  73   a ,  73   b  and  73   c  of the first back side encoder system  70 A is supplied to main controller  20  (refer to  FIG. 7 ). 
     Main controller  20  computes the position of fine movement stage WFS in the X-axis, the Y-axis and the Z-axis directions using the measurement values of three axes directions (X, Y, Z) of encoder  73   a , computes the position of fine movement stage WFS in the θz direction using the measurement values of the Y-axis direction of encoders  73   a  and  73   c , computes the position of fine movement stage WFS in the θy direction using the measurement value of the Z-axis direction of encoders  73   a  and  73   c , and computes the position of fine movement stage WFS in the θx direction using the measurement values of the Z-axis direction of encoders  73   a  and  73   b . Incidentally, the position of fine movement stage WFS in the θz direction can also be computed using the measurement values of the X-axis direction of encoders  73   a  and  73   b.    
     Here, in the present embodiment, detection point DP 1  of three-dimensional head  73   a  coincides with the exposure position in a planar view, and the position in the X-axis, the Y-axis and the Z-axis directions of fine movement stage WFS is measured at such detection point DP 1 . 
     With heads  73   a  to  73   c  described above, because the optical paths of the measurement beams in the air are extremely short and are substantially equal, the influence of air fluctuation can be practically ignored. Accordingly, position information of fine movement stage WFS in the directions of six degrees of freedom can be measured with high precision by the first back side encoder system  70 A. Further, because the substantial detection points on the grating in the X-axis, the Y-axis, and the Z-axis directions according to the first back side encoder system  70 A are each positioned right under the center (exposure position) of exposure area IA (coincide with the center of exposure area IA in a planar view), generation of the so-called Abbe error can be suppressed to a level that can be practically ignored. Accordingly, by using the first back side encoder system  70 A, main controller  20  can measure the position of fine movement stage WFS in the X-axis direction, the Y-axis direction and the Z-axis direction with high precision, without any Abbe errors. Incidentally, while it is also possible that the first back side encoder system  70 A measures only the position information of wafer table WTB 1  (or wafer stage WST 1 ) in the directions of six degrees of freedom, it is preferable that the first back side encoder system  70 A can measure the position information of wafer table WTB 1  (or wafer stage WST 1 ) using at least one measurement beam that is different from the plurality of measurement beams necessary for measurement of the position information in the directions of six degrees of freedom, as in the present embodiment. In such a case, main controller  20  uses the position information of wafer table WTB 1  (or wafer stage WST 1 ) measured by the first back side encoder system  70 A using at least one measurement beam different from the plurality of measurement beams necessary for the measurement of the position information in the directions of six degrees of freedom, and thereby, for example, can update information used to compensate for the measurement errors of the first back side encoder system  70 A that occurs due to grating RG. 
     Next, a structure and the like of the first top side encoder system  80 A structuring a part of the first fine movement stage position measurement system  110 A will be described. The first top side encoder system  80 A can measure position information of wafer table WTB 1  (fine movement stage WFS) in the directions of six degrees of freedom concurrently with the first back side encoder system  70 A. 
     In exposure apparatus  100 , for example as shown in  FIG. 2 , a pair of head sections  62 A and  62 C are placed on the +X side and the −X side of projection unit PU (nozzle unit  32 ), respectively. Head sections  62 A and  62 C, as will be described later on, each include a plurality of heads, and these heads are fixed to main frame BD (not shown in  FIG. 2 , refer to  FIG. 1  and the like) in a suspended state via a support member. 
     Head sections  62 A and  62 C, as shown in  FIG. 5 , are respectively equipped with five four-spindle heads  65   1  to  65   5  and five four-spindle heads  64   1  to  64   5 . Inside the respective housings of four-spindle heads  65   1  to  65   5 , XZ heads  65 X 1  to  65 X 5  whose measurement directions are in the X-axis and the Z-axis directions, and YZ heads  65 Y 1  to  65 Y 5  whose measurement directions are in the Y-axis and the Z-axis directions are housed. Similarly, inside the respective housings of four-spindle heads  64   1  to  64   5 , XZ heads  64 X 1  to  64 X 5  and YZ heads  64 Y 1  to  64 Y 5  are housed. As each of the XZ heads  65 X 1  to  65 X 5  and  64 X 1  to  64 X 5 , and YZ heads  65 Y 1  to  65 Y 5  and  64 Y 1  to  64 Y 5 , an encoder head having a structure similar to the displacement measurement sensor head disclosed in, for example, U.S. Pat. No. 7,561,280, can be used. 
     XZ heads  65 X 1  to  65 X 5  and  64 X 1  to  64 X 5  (to be more precise, irradiation points on scales  39   1  and  39   2  of the measurement beams generated by XZ heads  65 X 1  to  65 X 5  and  64 X 1  to  64 X 5 ) are placed on a straight line (hereinafter called a reference axis) LH which passes through optical axis AX (in the present embodiment, also coinciding with the center of exposure area IA previously described) of projection optical system PL and is also parallel to the X-axis, at a predetermined interval WD (refer to  FIG. 2 ). Further, YZ heads  65 Y 1  to  65 Y 5  and  64 Y 1  to  64 Y 5  (to be more precise, irradiation points on scales  39   1  and  39   2  of the measurement beams generated by YZ heads  65 Y 1  to  65 Y 5  and  64 Y 1  to  64 Y 5 ) are placed on a straight line LH 1  which is parallel to reference axis LH and is also a predetermined distance away from reference axis LH to the −Y side, at the same X positions as the corresponding XZ heads  65 X 1  to  65 X 5  and  64 X 1  to  64 X 5 . Hereinafter, XZ heads  65 X 1  to  65 X 5  and  64 X 1  to  64 X 5 , and YZ heads  65 Y 1  to  65 Y 5  and  64 Y 1  to  64 Y 5  will also be expressed as XZ heads  65 X and  64 X, and YZ heads  65 Y and  64 Y, respectively, as necessary. Incidentally, reference axis LH coincides with straight line LX 1  previously described. 
     Using scales  39   1  and  39   2  respectively, head sections  62 A and  62 C structure a multiple-lens (five-lens in this case) XZ linear encoder which measures the position in the X-axis direction (X position) and the position in the Z-axis direction (Z position) of wafer table WTB 1 , and structure a multiple-lens (five-lens in this case) YZ linear encoder which measures the position in the Y-axis direction (Y position) and the Z position. Hereinafter, for the sake of convenience, these encoders will be expressed as XZ linear encoders  65 X and  64 X, and YZ linear encoders  65 Y and  64 Y (refer to  FIG. 7 ), using the same reference signs as XZ heads  65 X and  64 X, and YZ heads  65 Y and  64 Y, respectively. 
     In the present embodiment, XZ linear encoders  65 X and YZ linear encoders  65 Y structure (refer to  FIG. 7 ) a multiple-lens (five-lens in this case) four-spindle encoder  65  which measures position information related to each of the X-axis, the Y-axis, the Z-axis and the θx directions of wafer table WTB 1 . Similarly, XZ linear encoders  64 X and YZ linear encoders  64 Y structure (refer to  FIG. 7 ) a multiple-lens (five-lens in this case) four-spindle encoder  64  which measures position information related to each of the X-axis, the Y-axis, the Z-axis, and the θx directions of wafer table WTB 1 . 
     Here, interval WD in the X-axis direction of the five XZ heads  65 X and  64 X (to be more precise, irradiation points on scales  39   1  and  39   2  of the measurement beams generated by XZ heads  65 X and  64 X) and the five YZ heads  65 Y and  64 Y (to be more precise, irradiation points on the scales of the measurement beams generated by YZ heads  65 Y and  64 Y) that head sections  62 A and  62 C are equipped with, respectively, is set narrower than the width of scales  39   1  and  39   2  in the X-axis direction. Accordingly, on exposure and the like, at least one head each of the five XZ heads  65 X, the five XZ heads  64 X, the five YZ heads  65 Y and the five YZ heads  64 Y constantly faces (irradiates the measurement beam on) the corresponding scales  39   1  and  39   2 . Here, the width of the scale refers to the width of the diffraction grating (or of an area where the diffraction grating is formed), or to be more precise, a range where position measurement using the head is possible. 
     Accordingly, four-spindle encoder  65  and four-spindle encoder  64  structure the first top side encoder system  80 A which measures position information in the directions of six degrees of freedom of wafer table WTB 1  (fine movement stage WFS) supported by coarse movement stage WCS, in the case when wafer stage WST 1  is at exposure station  200 . In this case, the position of wafer table WTB 1  (fine movement stage WFS) in the θy direction is obtained using the difference between the positions in the Z-axis direction measured, respectively, by four-spindle encoders  65  and four-spindle encoders  64 , and the position of wafer table WTB 1  (fine movement stage WFS) in the θz direction is obtained using the difference between the positions in the Y-axis direction measured, respectively, by four-spindle encoders  65  and four-spindle encoders  64 . 
     In the present embodiment, furthermore, a pair of four-spindle heads  65   6  and  64   6 , which are structured similar to four-spindle heads  65   1  to  65   5  and  64   1  to  64   5 , are placed symmetrically with respect to reference axis LV, on the −Y side of head sections  62 A and  62 C, respectively. XZ head  65 X 6  and YZ head  65 Y 6  structuring a four-spindle head  65   6  are placed at the same X-position as the XZ head  65 X 3 . XZ head  64 X 6  and YZ head  64 Y 6  structuring a four-spindle head  64   6  are placed at the same X-position as the XZ head  64 X 3 . 
     A pair of four-spindle heads  65   6  and  64   6  constitute a pair of encoders that measure position information of wafer table WTB 1  or WTB 2  in the directions of six degrees of freedom, using a pair of scales  39   1  and  39   2 , during a period from a time when a proximity or contact state (scrum) of measurement table MTB and wafer table WTB 1  or WTB 2  to be described later on is started until the position measurement of wafer table WTB 1  or WTB 2  by the first fine movement stage position measurement system  110 A is started, and this pair of encoders constitute a third fine movement stage position measurement system  110 C (refer to  FIG. 6 ). 
     Measurement values of each encoder structuring the first top side encoder system  80 A and the third fine movement stage position measurement system  110 C are supplied to main controller  20  (refer to  FIGS. 6, 7  and the like). 
     Further, although it is omitted in the drawings, when main controller  20  drives wafer stage WST 1  in the X-axis direction, main controller  20  sequentially switches XZ heads  65 X and  64 X and YZ heads  65 Y and  64 Y which measure position information of wafer table WTB 1  to adjacent XZ heads  65 X and  64 X and YZ heads  65 Y and  64 Y. That is, in order to smoothly perform this switching (joint) of such XZ heads and YZ heads, as previously described, interval WD of adjacent XZ heads and YZ heads included in head sections  62 A and  62 C is set smaller than the width of scales  39   1  and  39   2  in the X-axis direction. 
     As can be seen from the description so far, in the present embodiment, in the case when wafer stage WST 1  is located at exposure station  200 , position information in the directions of six degrees of freedom of wafer table WTB 1  (fine movement stage WFS) supported by coarse movement stage WCS can be measured concurrently by the first back side encoder system  70 A and the first top side encoder system  80 A. 
     In the case when wafer stage WST 2  is at exposure station  200 , the first back side encoder system  70 A that measures position information in the directions of six degrees of freedom of wafer table WTB 2  is structured, similarly to the above-described manner, by three-dimensional head  73   a , XZ head  73   b  and YZ head  73   c  that each irradiate a measurement beam on grating RG on the rear surface of wafer table WTB 2 , and in this case, the first top side encoder system  80 A that measures position information in the directions of six degrees of freedom of wafer table WTB 2  (fine movement stage WFS) supported by coarse movement stage WCS is structured, similarly to the above-described manner, by five-lens four-spindle encoders  65  and five-lens four-spindle encoders  64  each structured by the five four-spindle heads that head sections  62 A and  62 C respectively have, which irradiate measurement beams on the pair of scales  39   1  and  39   2 , respectively, on the upper surface of wafer table WTB 2 . 
     That is, in the present embodiment, regardless of which of wafer stage WST 1  or WST 2  is at exposure station  200 , the first back side encoder system  70 A which measures position information in the directions of six degrees of freedom of fine movement stage WFS is structured by heads  73   a  to  73   c  incorporated in arm member  71   1  facing grating RG equipped on fine movement stage WFS supported by coarse movement stage WCS located in exposure station  200 , and the first top side encoder system  80 A which measures position information in the directions of six degrees of freedom of fine movement stage WFS is structured by head sections  62 A and  62 C facing the pair of scales  39   1  and  39   2 , respectively, equipped on fine movement stage WFS supported by coarse movement stage WCS located in exposure station  200 . 
     The first top side encoder system  80 A and the first back side encoder system  70 A each have the following merits. 
     For the reasons such as, for example, that the first top side encoder system  80 A has the interval between the detection points of the plurality of heads used for position measurement in the θx, the θy and the θz directions is wide, compared with the first back side encoder system  70 A, at least regarding the position measurement in the θx, the θy and the θz directions, the coordinate system of the first top side encoder system  80 A is more reliable than the coordinate system of the first back side encoder system  70 A. 
     Meanwhile, the first back side encoder system  70 A has merits, for example, of having little long-term variation such as deformation of grating RG and drift and the like of heads  73   a  to  73   c , and high reliability in a static component of the measurement signal. 
     Therefore, in the present embodiment, when wafer stage WST 1  or WST 2  is positioned at exposure station  200  including the time of exposure to be described later on, main controller  20  performs measurement of position information of fine movement stage WFS (wafer table WTB 1  or WTB 2 ) concurrently by the first back side encoder system  70 A and the first top side encoder system  80 A, and performs position control of wafer table WTB 1  or WTB 2  based on the position information having higher reliability. In the description below, as an example, the position control of wafer table WTB 1  or WTB 2  is to be performed, based on the position information measured by the first back side encoder system  70 A for the X-axis, the Y-axis and the Z-axis directions, and based on the position information measured by the first top side encoder system  80 A for the θx, the θy and the θz directions. 
     Next, a structure of the second fine movement stage position measurement system  110 B (refer to  FIG. 6 ) used for measurement of position information of fine movement stage WFS, which is movably held by coarse movement stage WCS located at measurement station  300 , will be described. Here, the second fine movement stage position measurement system  110 B will be described, by describing, as an example, the case of measuring position information of wafer table WTB 2  that wafer stage WST 2  is equipped with. 
     The second back side encoder system  70 B of the second fine movement stage position measurement system  110 B is equipped with measurement arm  71 B (refer to  FIG. 1 ) which is inserted within a space provided inside coarse movement stage WCS, in a state where wafer stage WST 2  is placed below alignment detection system ALG. 
     Measurement arm  71 B, as shown in  FIG. 1 , has an arm member  71   2  which is supported by main frame BD via support member  72 B in a cantilevered state, and an encoder head (optical system) which will be described later on housed inside arm member  71   2 . While the length of arm member  71   2  is longer than arm member  71   1  previously described, measurement arm  71 B is structured substantially similar to measurement arm  71 A previously described, as a whole. 
     As previously described, in the state where wafer stage WST 2  is placed below alignment detection system ALG, as shown in  FIG. 1 , the tip of arm member  71   2  of measurement arm  71 B is inserted into the space of coarse movement stage WCS, and its upper surface faces grating RG (not shown in  FIG. 1 , refer to  FIG. 3B  and the like) provided on the lower surface of fine movement stage WFS (wafer table WTB) (to be more precise, the lower surface of main section  81 ). The upper surface of arm member  71   2  is placed almost parallel to the fine movement stage WFS lower surface, in a state where a predetermined clearance gap (gap, clearance), such as for example, a gap of around several mm, is formed between the upper surface of arm member  71   2  and the lower surface of fine movement stage WFS. 
     The second back side encoder system  70 B, as shown in  FIG. 7 , includes a three-dimensional encoder  75   a  which measures the position of fine movement stage WFS in each of the X-axis, the Y-axis and the Z-axis directions, an XZ encoder  75   b  which measures a position of fine movement stage WFS in the X-axis and the Z-axis directions, and a YZ encoder  75   c  which measures a position of fine movement stage WFS in the Y-axis and the Z-axis directions, similarly to the first back side encoder system  70 A previously described. 
     XZ encoder  75   b  and YZ encoder  75   c  are equipped, respectively, with a two-dimensional head whose measurement direction is in the X-axis and the Z-axis directions, and a two-dimensional head whose measurement direction is in the Y-axis and the Z-axis directions, each housed inside of arm member  71   2 . Hereinafter, for the sake of convenience, the two-dimensional heads that XZ encoder  75   b  and YZ encoder  75   c  respectively equipped with will be expressed as an XZ head  75   b  and a YZ head  75   c , using the same reference signs as the respective encoders. Three-dimensional encoder  75   a  is equipped with a three-dimensional head whose measurement direction is in the X-axis, the Y-axis and the Z-axis directions. Hereinafter, for the sake of convenience, the three-dimensional head that three-dimensional encoder  75   a  is equipped with will be expressed as a three-dimensional head  75   a , using the same reference sign of the encoder. As two-dimensional heads  75   b  and  75   c  and three-dimensional head  75   a , heads having structures similar to two-dimensional heads  73   b  and  73   c  and three-dimensional head  73   a  previously described can be used. 
     Three-dimensional head  75   a  and two-dimensional heads  75   b  and  75   c  are placed in a symmetrical but similar positional relation to three-dimensional head  73   a  and two-dimensional heads  73   b  and  73   c  previously described, inside of arm member  71   2 . The detection center of three-dimensional head  75   a  is located right under the alignment position, that is, coincides with the detection center of alignment detection system ALG in a planar view. 
     The output of the encoders  75   a  and  75   b  and  75   c  of the second back side encoder system  70 B is supplied to main controller  20  (refer to  FIGS. 6, 7  and the like). 
     Main controller  20  performs position measurement of wafer table WTB 2  in the directions of six degrees of freedom similar to the previously-described one, when wafer stage WST 2  is positioned at measurement station  300 , such as for example, at the time of wafer alignment which will be described later on, based on measurement values of of heads  75   a  to  75   c  of the second back side encoder system  70 B. The preceding description can be applied without any changes to the position measurement in this case, if the exposure position previously described is replaced to the alignment position. 
     Incidentally, in the present embodiment, the detection point of three-dimensional head  75   a  is located right under the alignment position, and the position of fine movement stage WFS in the X-axis, the Y-axis and the Z-axis directions is measured at that detection point 
     Further, because the substantial detection points on grating RG in the X-axis, the Y-axis and the Z-axis directions by the second back side encoder system  70 B each coincide with the detection center (alignment position) of alignment detection system ALG in a planar view, generation of the so-called Abbe error is suppressed to a level which can be substantially ignored. Accordingly, by using the second back side encoder system  70 B, main controller  20  can measure the position of fine movement stage WFS in the X-axis direction, the Y-axis direction and the Z-axis direction with high precision, without the Abbe error. 
     Next, a structure and the like of the second top side encoder system  80 B structuring a part of the second fine movement stage position measurement system  110 B will be described. The second top side encoder system  80 B can measure position information of wafer table WTB 2  (fine movement stage WFS) in the directions of six degrees of freedom concurrently with the second back side encoder system  70 B. 
     In exposure apparatus  100 , for example as shown in  FIG. 2 , on the −Y side of each of head sections  62 C and  62 A and at almost the same Y position as alignment detection system ALG, head sections  62 E and  62 F are placed, respectively. Head sections  62 E and  62 F, as described later on, each include a plurality of heads, and these heads are fixed to main frame BD in a suspended state via a support member. 
     Head sections  62 F and  62 E, as shown in  FIG. 5 , are equipped with five four-spindle heads  68   1  to  68   5 , and five  67   1  to  67   5 , respectively. Inside the respective housings of four-spindle heads  68   1  to  68   5 , similar to four-spindle heads  65   1  to  65   4  and the like previously described, XZ heads  68 X 1  to  68 X 5  and YZ heads  68 Y 1  to  68 Y 5  are housed. Similarly, inside the respective housings of four-spindle heads  67   1  to  67   5 , XZ heads  67 X 1  to  67 X 5  and YZ heads  67 Y 1  to  67 Y 5  are housed. As each of the XZ heads  68 X 1  to  68 X 5  and  67 X 1  to  67 X 5 , and YZ heads  68 Y 1  to  68 Y 5  and  67 Y 1  to  67 Y 5 , an encoder head having a structure similar to the displacement measurement sensor head disclosed in, for example, U.S. Pat. No. 7,561,280 can be used. 
     XZ heads  67 X 1  to  67 X 5  and  68 X 1  to  68 X 5  (to be more precise, irradiation points on scales  39   1  and  39   2  of the measurement beams generated by XZ heads  67 X 1  to  67 X 5  and  68 X 1  to  68 X 5 ) are placed along reference axis LA previously described, at almost the same X positions as XZ heads  64 X 1  to  64 X 5  and  65 X 1  to  65 X 5 , respectively. 
     YZ heads  67 Y 1  to  67 Y 5  and  68 Y 1  to  68 Y 5  (to be more precise, irradiation points on scales  39   1  and  39   2  of the measurement beams generated by YZ heads  67 Y 1  to  67 Y 5  and  68 Y 1  to  68 Y 5 ) are placed on a straight line LA 1  which is parallel to reference axis LA and is distanced to the −Y side from reference axis LA, at almost the same X position as the corresponding XZ heads  67 X 1  to  67 X 5  and  68 X 1  to  68 X 5 . Hereinafter, as necessary, XZ heads  68 X 1  to  68 X 5  and  67 X 1  to  67 X 5 , and YZ heads  68 Y 1  to  68 Y 5  and  67 Y 1  to  67 Y 5  will be expressed also as XZ heads  68 X and  67 X, and YZ heads  68 Y and  67 Y, respectively. 
     Using scales  39   1  and  39   2  respectively, head sections  62 F and  62 E structure a multiple-lens (five-lens in this case) XZ linear encoder which measures the X position and the Z position of wafer table WTB 2 , and a multiple-lens (five-lens in this case) YZ linear encoder which measures the Y position and the Z position. Hereinafter, for the sake of convenience, these encoders will be expressed as XZ linear encoders  68 X and  67 X and YZ linear encoders  68 Y and  67 Y (refer to  FIG. 7 ), using the same reference signs as XZ heads  68 X and  67 X, and YZ heads  68 Y and  67 Y, respectively. 
     In the present embodiment, XZ linear encoders  68 X and YZ linear encoders  68 Y structure (refer to  FIG. 7 ) a multiple-lens (five-lens in this case) four-spindle encoder  68  which measures position information of wafer table WTB 2  related to each of the X-axis, the Y-axis, the Z-axis and the θx directions. Similarly, XZ linear encoders  67 X and YZ linear encoders  67 Y structure (refer to  FIG. 7 ) a multiple-lens (five-lens in this case) four-spindle encoder  67  which measures position information of wafer table WTB 2  related to each of the X-axis, the Y-axis, the Z-axis and the θx directions. 
     Here, for the similar reason to the previously-described reason, on alignment measurement and the like, at least one head each of the five XZ heads  68 X, the five XZ heads  67 X, the five YZ heads  68 Y and the five YZ heads  67 Y constantly faces (irradiates a measurement beam on) the corresponding scales  39   1  and  39   2 . Accordingly, four-spindle encoder  68  and four-spindle encoder  67  structure the second top side encoder system  80 B which measures position information in the directions of six degrees of freedom of wafer table WTB 2  (fine movement stage WFS) supported by coarse movement stage WCS, in the case when wafer stage WST 2  is at measurement station  300 . 
     Measurement values of each encoder structuring the second top side encoder system  80 B are supplied to main controller  20  (refer to  FIGS. 6, 7  and the like). 
     As is obvious from the description so far, in the present embodiment, in the case when wafer stage WST 2  is at measurement station  300 , position information in the directions of six degrees of freedom of wafer table WTB 2  (fine movement stage WFS) supported by coarse movement stage WCS can be measured concurrently by the second back side encoder system  70 B and the second top side encoder system  80 B. 
     In the case when wafer stage WST 1  is at measurement stage  300 , the second back side encoder system  70 B that measures position information of wafer table WTB 1  in the directions of six degrees of freedom is structured, similarly to the above-described manner, by three-dimensional head  75   a , XZ head  75   b  and YZ head  75   c  that each irradiate a measurement beam on grating RG on the rear surface of wafer table WTB 1 . Further, in this case, the second top side encoder system  80 B that measures position information of wafer table WTB 1  (fine movement stage WFS) supported by coarse movement stage WCS in the directions of six degrees of freedom is structured, similarly to the above-described manner, by five-lens four-spindle encoder  68  and five-lens four-spindle encoder  67  each structured by the five four-spindle heads that head sections  62 F and  62 E respectively have, which irradiate measurement beams on the pair of scales  39   1  and  39   2 , respectively, on the upper surface of wafer table WTB 1 . 
     That is, in the present embodiment, regardless of which of wafer stage WST 1  or WST 2  is at measurement station  300 , the second back side encoder system  70 B which measures position information in the directions of six degrees of freedom of fine movement stage WFS is structured by heads  75   a  to  75   c  incorporated in arm member  71   2  facing grating RG equipped on fine movement stage WFS supported by coarse movement stage WCS located in measurement station  300 , and the second top side encoder system  80 B which measures position information in the directions of six degrees of freedom of fine movement stage WFS is structured by head sections  62 A and  62 C facing the pair of scale  39   1  and  39   2 , respectively, equipped on fine movement stage WFS supported by coarse movement stage WCS located in measurement station  300 . 
     However, the second top side encoder system  80 B and the second back side encoder system  70 B have the merits and demerits similar to those of the first top side encoder system  80 A and the first back side encoder system  70 A described previously. 
     Therefore, in the present embodiment, when wafer stage WST 1  or WST 2  is positioned at measurement station  300  including the time of alignment to be described later on, main controller  20  performs measurement of position information of fine movement stage WFS (wafer table WTB 1  or WTB 2 ) concurrently by the second back side encoder system  70 B and the second top side encoder system  80 B, and performs position control of wafer table WTB 1  or WTB 2  based on the position information having higher reliability. In the description below, as an example, the position control of wafer table WTB 1  or WTB 2  is to be performed, based on the position information measured by the second back side encoder system  70 B for the X-axis, the Y-axis and the Z-axis directions, and based on the position information measured by the second top side encoder system  80 B for the θx, the θy and the θz directions. 
     Incidentally, regarding the second back side encoder system  70 B and the second top side encoder system  80 B of the second fine movement stage position measurement system  110 B, besides the details described so far, the preceding description about the first back side encoder system  70 A and the first top side encoder system  80 A can be applied without any changes. 
     In the present embodiment, a third top side encoder system  80 C is also provided (refer to  FIG. 6 ) that measures position information of measurement table MTB in the directions of six degrees of freedom of when measurement table MTB (measurement stage MST) moves from a standby position shown in  FIG. 2  to a scrum position to be described later on, or reversely, when measurement table MTB returns from the scrum position to the standby position. The third top side encoder system  80 C, as shown in  FIG. 2 , includes a pair of four-spindle heads  66   1  and  66   2  placed adjacent to each other in the X-axis direction at a position capable of facing two-dimensional grating  69  (refer to  FIG. 4B ) provided at measurement table MTB of measurement stage MST located at the standby position, a pair of four-spindle heads  66   3  and  66   4  placed a predetermined distance away to the −Y direction from the pair of four-spindle heads  66   1  and  66   2 , and a pair of four-spindle heads  66   5  and  66   6  placed adjacent to each other in the X-axis direction at a position halfway between the pair of four-spindle heads  66   3  and  66   4  and the two four-spindle heads  64   4  and  64   5  of head section  62 C described previously. 
     The pair of four-spindle heads  66   1  and  66   2 , the pair of four-spindle heads  66   3  and  66   4  and the pair of four-spindle heads  66   5  and  66   6  are each fixed to main frame BD in a suspended state via a support member. 
     Each of four-spindle heads  66   1 ,  66   2 ,  66   3 ,  66   4 ,  66   5  and  66   6  includes one XZ head and one YZ head having detection points placed along the Y-axis direction, similarly to four-spindle heads  64 ,  65 ,  67  and  68  described previously. The pair of four-spindle heads  66   1  and  66   2 , the pair of four-spindle heads  66   3  and  66   4  and the pair of four-spindle heads  66   5  and  66   6  each structure a pair of four-spindle encoders that measure position information of measurement table MTB in the directions of six degrees of freedom using two-dimensional grating  69  provided at measurement table MTB. These three pairs of four-spindle encoders structure the third top side encoder system  80 C. The measurement values of each of the encoders that structure the third top side encoder system  80 C are supplied to main controller  20  (refer to  FIG. 6  and the like). 
     The third top side encoder system  80 C and a plurality of encoder systems structured by heads  73   a  to  73   c  described previously, that measurement arm  71 A has, which irradiate measurement beams on grating RGa on the rear surface of measurement table MTB, structure a measurement table position measurement system  16  (refer to  FIG. 6 ). Incidentally, measurement table position measurement system  16  does not necessarily have to have heads  73   a  to  73   c  described previously, and for example, can have only the third top side encoder system  80 C. In this case, it is also possible that the placement (position) of the heads shown in  FIG. 2  is changed or at least one head is added, thereby allowing position information of measurement stage MST to be measured by the third top side encoder system  80 C during the scrum operation described previously as well. 
     In the present embodiment, further, measurement system  80 D is provided (refer to  FIG. 6 ) that is used to measure a position within the XY plane of wafer stage WST 1  or WST 2  that is moving, when wafer stage WST 1  or WST 2  moves between measurement station  300  and exposure station  200 . This measurement system  80 D has a plurality of Hall elements placed at a predetermined interval within an area between reference axis LH and reference axis LA inside base board  12 . Measurement system  80 D measures the approximate position within the XY plane of wafer stage WST 1  or WST 2 , using a change in magnetic field occurring by magnets provided on the bottom surfaces of each coarse movement stage WCS when wafer stage WST 1  or WST 2  moves within the XY plane. Measurement information of this measurement system  80 D is supplied to main controller  20  (refer to  FIG. 6 ). Incidentally, a measurement device that measures position information of wafer stage WST 1  or WST 2  in a range where measurement of the position information of wafer stage WST 1  or WST 2  by the first and the second fine movement stage position measurement systems  110 A and  110 B cannot be performed, that is, a range outside the measurement ranges described previously is not limited to measurement system  80 D, and for example, an interferometer system or an encoder system that employs a same detection method and/or a same structure as or a different detection method and/or a different structure from the first and the second top side encoder systems described previously can be used. 
     Besides this, in exposure apparatus  100 , an exposure coordinate setting measurement system  34  (refer to  FIG. 6 ) is placed at a position in the vicinity of exposure station  200 , and measures an absolute coordinate of wafer table WTB 1  or WTB 2  for origin return of the third fine movement stage position measurement system  110 C at the point when wafer stage WST 1  or WST 2  moves from a measurement station  300  side to an exposure station  200  side and wafer table WTB 1  or WTB 2  comes in proximity to or contact with measurement table MTB, as it will be described later on. As it will be described later on, origin return of the first back side encoder system  70 A and the first top side encoder system  80 A of the first fine movement stage position measurement system  110 A is performed, using measurement values of the third fine movement stage position measurement system  110 C on which origin return (reset) has been performed. 
     Exposure coordinate setting measurement system  34 , as shown in  FIG. 2 , includes a pair of imaging sensors  36   a  and  36   b , which are placed at positions a predetermined distance away to the −Y side (for example, a distance of around one third of the Y-axis direction length of wafer table WTB 1 ) of head sections  62 A and  62 C, set apart on the +X side and the −X side of reference axis LV by a same distance from reference axis LV which is slightly shorter than half the length in the X-axis direction of wafer table WTB 1 , a pair of Z sensors  38   a  and  38   b  which are placed adjacent on the +Y side of the pair of imaging sensors  36   a  and  36   b , respectively, and a Z sensor  38   c  which is placed set apart to the −Y side of Z sensor  38   a , for example, by a distance of around half the length in the Y-axis direction of wafer table WTB 1 . These imaging sensors  36   a  and  36   b , and Z sensors  38   a  to  38   c  are each fixed in a suspended state to main frame BD via a support member. 
     The pair of imaging sensors  36   a  and  36   b  image marks previously described which are each provided on the edge on both sides in the X-axis direction of wafer table WTB 1  (or WTB 2 ) when wafer table WTB 1  (or WTB 2 ) is at a predetermined position, in this case, a position where a proximity or contact state to be described later with respect to measurement table MTB (scrum) begins (scrum starting position), and measures the X and the Y positions of the marks subject to imaging, with the detection center serving as a reference. Z sensors  38   a  to  38   c , for example, are made up of heads of optical displacement sensors similar to optical pick-ups used in CD driving devices and the like and each measure the Z position of the upper surface of wafer table WTB 1  (or WTB 2 ). Measurement values of such imaging sensors  36   a  and  36   b  and Z sensors  38   a  to  38   c  are supplied to main controller  20 . 
     Accordingly, main controller  20  performs origin return of the third fine movement stage position measurement system  110 C, by measuring the position in the directions of six degrees of freedom of wafer table WTB 1  or WTB 2  simultaneously with exposure coordinate setting measurement system  34  and the third fine movement stage position measurement system  110 C, and re-setting the measurement values of a pair of encoders made up of the pair of four-spindle heads  65   6  and  64   6  that structure the third fine movement stage position measurement system  110 C, using the measurement values (absolute positions) of imaging sensors  36   a  and  36   b  and Z sensors  38   a  to  38   c . Then, after such operation, by making the origin return of the first back side encoder system  70 A and the first top side encoder system  80 A of the first fine movement stage position measurement system  110 A which measures the position, in the directions of six degrees of freedom, of wafer table WTB 1  (or WTB 2 ) located at exposure station  200 , with the measurement values of the third fine movement stage position measurement system  110 C after the origin return serving as a reference, a coordinate system which controls the position of wafer table WTB 1  (or WTB 2 ) at the time of exposure (exposure-time coordinate system) can be returned. 
     In exposure apparatus  100 , further, a measurement coordinate setting measurement system  35  (refer to  FIG. 6 ) is provided that is placed at a position in the vicinity of measurement station  300 , and measures an absolute coordinate of wafer table WTB 2  or WTB 1  when wafer stage WST 2  or WST 1  moves to a loading position to be described later on, for origin return of the second back side encoder system  70 B and the second top side encoder system  80 B of the second fine movement stage position measurement system  110 B. 
     Measurement coordinate setting measurement system  35 , as shown in  FIG. 2 , includes a pair of imaging sensors  36   c  and  36   d  which are placed at positions a predetermined distance away to the −Y side of head sections  62 F and  62 E, set apart from reference axis LV by a same distance which is slightly shorter than half the length in the X-axis direction of wafer table WTB 2 , a pair of Z sensors  38   d  and  38   e  which are placed adjacent on the +Y side of the pair of imaging sensors  36   c  and  36   d , respectively, close to the −Y side of head sections  62 F and  62 E, and a Z sensor  38   f  which is placed set apart to the −Y side of Z sensor  38   d , for example, by a distance of around half the length in the Y-axis direction of wafer table WTB 2 . These imaging sensors  36   c  and  36   d  and Z sensors  38   d  to  38   f  are each fixed in a suspended state to main frame BD via a support member. 
     The pair of imaging sensors  36   c  and  36   d  image the marks previously described each provided on the edge on both sides in the X-axis direction of wafer table WTB 2  (or WTB 1 ), and measures the X and the Y positions of the marks subject to imaging, with the detection center serving as a reference. Z sensors  38   d  to  38   f , for example, are made up of heads of optical displacement sensors similar to Z sensors  38   a  to  38   c  previously described, and each measure the Z position of the upper surface of wafer table WTB 2  (or WTB 1 ). Measurement values of such imaging sensors  36   c  and  36   d  and Z sensors  38   d  to  38   f  are supplied to main controller  20 . 
     Accordingly, by main controller  20  simultaneously measuring the position of wafer table WTB 2  or WTB 1  using measurement coordinate setting measurement system  35  and the second fine movement stage position measurement system  110 B when wafer stage WST 2  or WST 1  moves to a loading position to be described later on, and making the origin of the second back side encoder system  70 B and the second top side encoder system  80 B of the second fine movement stage position measurement system  110 B return using the measurement values (absolute positions) of imaging sensors  36   c  and  36   d  and Z sensors  38   d  to  38   f , return of a coordinate system, which controls a position of wafer table WTB 2  (or WTB 1 ) located at measurement station  300  at the time when a series of measurements to be described later including alignment measurement and the like are performed (measurement-time coordinate system), becomes possible. 
     In exposure apparatus  100  of the present embodiment, as shown in  FIG. 5 , an unloading position UP 1  is set at a predetermined position between the exposure position and the alignment position on reference axis LV, as an example, at a position away from alignment detection system ALG by a predetermined distance on reference axis LV, for example, a distance of around two thirds of the Y-axis direction length of wafer table WTB 2  to the +Y direction, and waiting positions UP 2  and UP 3  are set at positions the same predetermined distance away to the +X side and the −X side from unloading position UP 1 , respectively. 
     At unloading position UP 1 , a first unloading slider (not shown) is provided made up of an arm member which approaches from above wafer W that has been exposed and is supported above the wafer holder by the vertical movement pin previously described, grasps the side surface of the wafer at a plurality of places, and lifts the wafer upward. The first unloading slider can hold the wafer in a non-contact state with the surface of the wafer. The first unloading slider is attached to main frame BD via a vibration isolation member which is not shown. 
     At wafer waiting position UP 2 , a second unloading slider (not shown) is provided that receives from below wafer W held by the first unloading slider and holds the wafer, and is vertically movable and can carry the wafer to a delivery position of the wafer to an external device through a path at the edge on the +X side above base board  12 . Similarly, at wafer waiting position UP 3 , a third unloading slider (not shown) is provided which receives from below wafer W held by the first unloading slider and holds the wafer, and is vertically movable and can carry the wafer to a delivery position of the wafer to an external device through a path at the edge on the −X side above base board  12 . The second and the third unloading sliders are supported by another frame which is vibrationally separated from main frame BD. Incidentally, a device used to unload the wafer is not limited to the structure described above, and any device that can move holding wafer W may be employed. Further, the unloading position of wafer W is not limited to being set between projection optical system PL and alignment detections system ALG, and for example, the unloading can be performed on a side opposite to projection optical system PL with respect to alignment detection system ALG as in a modified example to be described later on. 
     Further, in the present embodiment, as shown in  FIG. 2 , loading position LP is set at a position where fiducial mark FM on measurement plate  30  is positioned in the field (detection area) of alignment detection system ALG (that is, a position where the first half processing of the baseline measurement (BCHK) of alignment detection system ALG is performed). 
       FIG. 6  shows a block diagram showing an input/output relation of main controller  20  which mainly structures a control system of exposure apparatus  100  and has overall control over each structuring parts. Main controller  20  includes a workstation (or a microcomputer) and the like, and has overall control over each of the parts that structure exposure apparatus  100 .  FIG. 7  shows an example of a concrete structure of the first and the second fine movement stage position measurement systems  110 A and  110 B in  FIG. 6 . 
     Next, a concurrent processing operation using wafer stages WST 1  and WST 2  and measurement stage MST in exposure apparatus  100  related to the present embodiment will be described, based on  FIGS. 9 to 20 . Incidentally, in the following operation, main controller  20  performs control of liquid supply device  5  and liquid recovery device  6  of local liquid immersion device  8  as is previously described, and water is constantly filled in an area right under tip lens  191  of projection optical system PL. However, in the description below, for a straightforward description, description related to the control of liquid supply device  5  and liquid recovery device  6  will be omitted. Further, in  FIGS. 9 to 20 , the illustration of base board  12 , tube carriers TC 1  and TC 2  and the like is omitted. Further, while a number of drawings will be used in the description on the operation hereinafter, the same member may or may not have a reference sign applied in each of the drawings. That is, although the reference sign written for each of the drawings may be different, these drawings show the same structure, regardless of the availability of reference signs. The same is said for each of the drawings used in the description so far. Further, in  FIG. 9  and the subsequent drawings, measurement stage MST is shown simplified. 
     Further, when each head of the first and the second back side encoder systems  70 A and  70 B and the first to the third top side encoder systems  80 A to  80 C, the AF system, the alignment detection system and the like are used, or a little before their usage, their state is set from an OFF state to an ON state, but the description regarding this point will be omitted when describing the operation hereinafter. 
       FIG. 9  shows a situation where wafer stage WST 2  which holds a wafer before exposure (referred to as W 2 ) on which wafer alignment measurement and focus mapping to be described later have been completed waits at a predetermined standby position, and an area on the +X side half of a wafer held on wafer table WTB 1  (refer to as W 1 ) is exposed while wafer stage WST 1  is moved along a path shown by a black arrow in  FIG. 9  by main controller  20 . The exposure of the area on the +X side half of wafer W 1  is performed in the order of a shot area on the −Y side to a shot area on the +Y side. Prior to this, exposure of the area on the −X side half of wafer W 1  is completed in the order of a shot area on the +Y side to the shot area on the −Y side, while being moved along a path as shown by a black arrow for wafer stage WST 2  in  FIG. 16 . By this operation, at the point when exposure of all the shot areas of wafer W 1  has been completed, wafer stage WST 1  returns to substantially the same position as the position before starting exposure. Incidentally, at this point in time, the position of wafer stage WST 2  is controlled by main controller  20 , based on the measurement values of measurement system  80 D previously described. 
     While, in the present embodiment, the exposure order described above of the shot areas is employed, the total length of the path in which wafer stage WST moves for exposure, in the case when a wafer of the same size is exposed according to the same shot map, is not much different from a conventional liquid immersion scanner and the like, disclosed in, for example, U.S. Patent Application Publication No. 2008/0088843 and the like. 
     During the exposure described above, the measurement values of the first fine movement stage position measurement system  110 A, namely, the measurement values of four-spindle heads  65  and  64  facing scales  39   1  and  39   2 , respectively, or namely, position information (measurement values of the position) of wafer table WTB 1  in the directions of six degrees of freedom measured by the first top side encoder system  80 A previously described, and the position information (measurement values of the position) of wafer table WTB 1  in the directions of six degrees of freedom measured by the first back side encoder system  70 A are supplied to main controller  20 , and based on the measurement value having higher reliability of the supplied measurement values, servo control of the position of wafer table WTB 1  is performed by main controller  20 . Further, control of the position in the Z-axis direction, the θy rotation, and the θx rotation of wafer table WTB 1  (focus-leveling control of wafer W) during this exposure is performed based on results of the focus mapping (which will be described later on) performed in advance. 
     During the exposure operation by the step-and-scan method described above, when wafer stage WST 1  moves in the X-axis direction, accompanying the movement, switching of heads of the first top side encoder system  80 A (succession of measurement values between a plurality of heads) is performed. As described above, main controller  20  appropriately switches the encoder to be used of the first top side encoder system  80 A according to the position coordinate of wafer stage WST 1 , and drives wafer stage WST 1 . 
     Concurrently with the exposure of shot areas on the +X side half of the wafer described above, a wafer having undergone exposure (refer to as W 0 ) which has been carried from waiting position UL 3  to the delivery position prior to the exposure, is delivered to a wafer carrier system (not shown) to be carried outside the apparatus by a carrier robot not shown. 
     Concurrently with the exposure of the shot areas on the +X side half of wafer W 1  described above, main controller  20 , furthermore, drives measurement stage MST within the XY plane, from a standby position shown by an imaginary line in  FIG. 9  to a scrum position shown by a solid line, based on the measurement values of the third top side encoder system  80 C. Main controller  20  performs the drive of measurement stage MST by switching the four-spindle heads of the third top side encoder system  80 C. By this drive, wafer stage WST 1  and measurement stage MST distanced from each other during exposure move into a state where wafer table WTB 1  and measurement table MTB are in contact or proximity (also called a scrum state). When moving into this contact or proximity state, measurement stage MST engages with measurement arm  71 A from the side (laterally). In order to allow this engagement of the measurement stage MST with measurement arm  71 A from the side, measurement table MTB of measurement stage MST is supported in a cantilevered manner via support section  62  on slider section  60 . 
     Then, main controller  20  moves measurement stage MST in the −Y direction and also moves wafer stage WST 1  in the −Y direction as well as in the −X direction as is shown by two outlined arrows in  FIG. 10 , while maintaining the contact or proximity state of wafer table WTB 1  and measurement table MTB described above. This moves (delivers) a liquid immersion area  14  (liquid Lq) formed below projection unit PU from wafer table WTB 1  onto measurement table MTB, and liquid immersion area  14  (liquid Lq) is held by projection optical system PL and measurement table MTB. Further, the reason for moving wafer stage WST 1  also in the −X direction in this operation, is that the next operation, namely, an exchanging operation of wafer stage WST 1  and wafer stage WST 2 , can be started within a short time after the exposure has been completed. 
     At the stage when delivery of liquid immersion area (liquid Lq) from wafer table WTB 1  onto measurement table MTB described above has been completed, main controller  20  can control the position of measurement table MTB via measurement table driving system  52 C (refer to  FIG. 6 ), based on measurement values of the first back side encoder system  70 A which uses grating RG provided on the rear surface of measurement table MTB. Accordingly, main controller  20  can perform measurement operations related to exposure that are necessary, while controlling the position in the directions of six degrees of freedom of measurement table MTB. 
     After moving into the contact or proximity state described above, just before movement of liquid immersion area  14  (liquid Lq) from wafer table WTB 1  onto measurement table MTB is completed, wafer stage WST 1  moves out of the measurement range of the first fine movement stage position measurement system  110 A, and position measurement of wafer table WTB 1  by the first top side encoder system  80 A and the first back side encoder system  70 A can no longer be performed. Just before this, main controller  20  switches the position measurement system used to control the position of wafer stage WST 1  (wafer table WTB 1 ) from the first fine movement stage position measurement system  110 A to measurement system  80 D previously described. 
     After that, as is shown by an outlined arrow in  FIG. 11 , main controller  20  drives wafer stage WST 1  in the −X direction to a position where wafer stage WST 1  no longer faces wafer stage WST 2  (refer to  FIG. 12 ) that is still waiting at the standby position previously described at this point in time. 
     Next, main controller  20  drives wafer stage WST 2  in the +Y direction concurrently with driving wafer stage WST 1  in the −Y direction, as respectively shown by outlined arrows in  FIG. 12 . After the contact or proximity state previously described is released by this drive, wafer stage WST 1  moves to below waiting position UP 3  described previously. Concurrently with this, wafer stage WST 2  moves to a position where the −X side edge of the +Y side surface of wafer table WTB 2  is in contact or proximity in the Y-axis direction with/to the +X side edge of a −Y side surface of measurement table MTB which holds liquid immersion area  14  (liquid Lq) with projection optical system PL (refer to  FIG. 13 ). 
     Next, as each shown by an outlined arrow in  FIG. 13 , main controller  20  drives wafer stage WST 2  in the −X direction, concurrently with driving wafer stage WST 1  in the +X direction. This moves wafer stage WST 2  to a position where imaging sensors  36   a  and  36   b  and Z sensors  38   a  to  38   c  of exposure coordinate setting measurement system  34  simultaneously face wafer table WTB 2 , as well as moving wafer stage WST 1  to unloading position UP 1 , from below waiting position UP 3  (refer to  FIG. 14 ). 
     When wafer stage WST 2  moves to the position shown in  FIG. 14 , main controller  20  temporarily switches the position measurement system used to control the position of wafer table WTB 2  (wafer stage WST 2 ) from measurement system  80 D previously described to the third fine movement stage position measurement system  110 C. That is, main controller  20  performs origin return of the third fine movement stage position measurement system  110 C, by simultaneously measuring the position in the directions of six degrees of freedom of wafer table WTB 2  with exposure coordinate setting measurement system  34  and the third fine movement stage position measurement system  110 C, and re-setting the measurement values of a pair of encoders made up of the pair of four-spindle heads  65   6  and  64   6  structuring the third fine movement stage position measurement system  110 C, using the measurement values (absolute positions) of exposure coordinate setting measurement system  34  (imaging sensors  36   a  and  36   b  and Z sensors  38   a  to  38   c ). Afterwards, the position of wafer table WTB 2  is controlled based on the measurement values according to the third fine movement stage position measurement system  110 C. Further, in a state where wafer stage WST 2  is moved to the position shown in  FIG. 14 , wafer table WTB 2  is in a contact or proximity state (scrum state) in the Y-axis direction with measurement table MTB for delivery of the liquid immersion area. That is, in the present embodiment, it is decided that origin return (reset of measurement values) of the third fine movement stage position measurement system  110 C is to be performed at the scrum starting position of wafer table WTB 2  with respect to measurement table MTB, and the mark previously described is provided at a predetermined position on wafer table WTB 2  so that the origin return of the third fine movement stage position measurement system  110 C can be performed at this scrum starting position. 
     In the present embodiment, in at least a part of a period after projection optical system PL and measurement table MTB begin to hold liquid immersion area  14  (liquid Lq) as previously described until the scrum of wafer table WTB 2  with measurement table MTB begins, main controller  20 , by using at least one of measurement members that measurement table MTB has, namely, illuminance irregularity sensor  95 , aerial image measuring device  96 , wavefront aberration measuring device  97  and illuminance monitor  98  that are previously described, can perform when necessary at least one measurement related to exposure in which illumination light IL is received via a light-receiving surface of each measuring device via projection optical system PL and liquid Lq, or in other words, at least one of an uneven illuminance measurement, an aerial image measurement, a wavefront aberration measurement and a dose measurement. 
     Meanwhile, when wafer stage WST 1  reaches unloading position UP 1 , main controller  20  releases the suction by the wafer holder of wafer W which has been exposed, and drives the vertical movement pin (not shown) upward by a predetermined amount and lifts wafer W 1 . The position of the vertical movement pin at this point is maintained until wafer stage WST 1  reaches loading position LP, and the loading of the next wafer begins. 
     Then, main controller  20  lifts wafer W 1  using the first unloading slider by holding wafer W 1  from above as is previously described, and unloads wafer W 1  from wafer stage WST 1 . After that, wafer W 1  is maintained at the position above unloading position UP 1  until wafer stage WST 1  approaches loading position LP. 
     Next, main controller  20  drives wafer stage WST 2  and measurement stage MST in the +Y direction as is shown by two outlined arrows pointing upward in  FIG. 14 , while maintaining the contact or proximity state of wafer table WTB 2  and measurement table MTB. By this drive, liquid immersion area  14  (liquid Lq) formed below projection unit PU is moved (delivered) from measurement table MTB onto wafer table WTB 2 , and liquid immersion area  14  (liquid Lq) is to be held by projection optical system PL and wafer table WTB 2  (refer to  FIG. 15 ). 
     At the point when the delivery of liquid immersion area  14  described above has been completed, measurement arm  71 A is inserted into a space of wafer stage WST 2 , and the rear surface (grating RG) of wafer table WTB 2  faces heads  73   a  to  73   c  of measurement arm  71 A, and head sections  62 A and  62 C face scale  39   1  and  39   2  (refer to  FIG. 15 ). That is, the position of wafer table WTB 2  can be measured by the third fine movement stage position measurement system  110 C, as well as by the first fine movement stage position measurement system  110 A. Therefore, main controller  20  re-sets the measurement values of the first back side encoder system  70 A and the first top side encoder system  80 A of the first fine movement stage position measurement system  110 A, based on the position coordinate in the directions of six degrees of freedom of wafer table WTB 2  measured by the third fine movement stage position measurement system  110 C, so as to perform origin return of the first back side encoder system  70 A and the first top side encoder system  80 A. In the manner described above, return of the exposure-time coordinate system which controls the position of wafer table WTB 2  that moves within exposure station  200  is performed. Incidentally, if the position in the directions of six degrees of freedom of wafer table WTB 2  can be measured simultaneously by the first fine movement stage position measurement system  110 A and exposure coordinate setting measurement system  34 , the origins of the first back side encoder system  70 A and the first top side encoder system  80 A can be returned, according to a method similar to the origin return of the third fine movement stage position measurement system  110 C previously described. 
     After the return of the exposure-time coordinate system described above, main controller  20  controls the position of wafer table WTB 2 , based on position information having higher reliability out of the position information from the first back side encoder system  70 A and the position information from the first top side encoder system  80 A. 
     Concurrently with the drive in the +Y direction of wafer stage WST 2  and measurement stage MST for the delivery of liquid immersion area  14  described above, main controller  20  drives wafer stage WST 1  toward loading position LP. Halfway along this drive, position measurement of wafer stage WST 1  (wafer table WTB 1 ) by measurement system  80 D can no longer be performed. Therefore, before wafer stage WST 1  falls out of the measurement range by measurement system  80 D, for example, at the point when wafer stage WST 1  reaches the position shown by an imaginary line (two-dot chain line) in  FIG. 15 , main controller  20  switches the position measurement system used for the position control of wafer table WTB 1  (wafer stage WST 1 ) from measurement system  80 D previously described to the second fine movement stage position measurement system  110 B. That is, at the point when wafer stage WST 1  has reached the position shown by the imaginary line (two-dot chain line) in  FIG. 15 , measurement arm  71 B is inserted into a space of wafer stage WST 1 , and the rear surface (grating RG) of wafer table WTB 1  faces heads  75   a  to  75   c  of measurement arm  71 B, and head sections  62 F and  62 E face scales  39   1  and  39   2 . Further, at this point in time, measurement of the absolute position in the directions of six degrees of freedom of wafer table WTB 1  by measurement coordinate setting measurement system  35  is possible. Therefore, main controller  20  simultaneously measures the position in the directions of six degrees of freedom of wafer table WTB 1 , using measurement coordinate setting measurement system  35  and the second fine movement stage position measurement system  110 B. And, similarly to the above-described manner, main controller  20  re-sets the measurement values of the second back side encoder system  70 B and the second top side encoder system  80 B of the second fine movement stage position measurement system  110 B, based on the absolute position of wafer table WTB 1  measured by measurement coordinate setting measurement system  35 , so as to perform origin return of the second back side encoder system  70 B and the second top side encoder system  80 B. In the manner described above, return of the measurement-time coordinate system which controls the position of wafer table WTB 1  that moves within measurement station  300  is performed. 
     Measurement coordinate setting measurement system  35  can measure the absolute position in the directions of six degrees of freedom of wafer table WTB 1 , and therefore, the switching from measurement system  80 D to the second fine movement stage position measurement system  110 B described above, namely, the return of the measurement-time coordinate system described above, can be performed within a short time. 
     After the return of the measurement-time coordinate system described above, main controller  20  sets the position of wafer stage WST 1  to loading position LP, while controlling the position of wafer table WTB 1  based on position information having higher reliability out of the position information from the second back side encoder system  70 B and the position information from the second top side encoder system  80 B (refer to  FIG. 15 ). 
     When wafer stage WST 1  is driven toward loading position LP and is moved away from unloading position UP 1 , wafer W 1  located above unloading position UP 1  is moved to waiting position UP 2 , as typically shown by a black arrow in  FIG. 15 . This movement is performed by main controller  20  in the following procedure. 
     That is, main controller  20  moves the second unloading slider to below wafer W 1  which is located above unloading position UP 1 , and after delivering wafer W 1  from the first unloading slider to the second unloading slider, moves the second unloading slider holding wafer W 1  to waiting position UP 2 . The state of this wafer W 1  being held by the second unloading slider at a position of a predetermined height at waiting position UP 2  is maintained, until a series of measurement operations to the next wafer, that is, the alignment measurement, the focus mapping and the like are completed and wafer stage WST 2  is moved to a predetermined standby position. 
     At loading position LP, a new wafer W 3  (here, as an example, the wafer is to be a wafer in the middle of a lot (1 lot including 25 or 50 slices of wafers)) which has not yet undergone exposure is loaded onto wafer stage WST 1  in the procedure described below. That is, wafer W 3  held by a loading arm not shown is delivered to the vertical movement pin which maintains a state of moving upward by a predetermined amount from the loading arm, and after the loading arm has withdrawn, by the vertical movement pin moving downward, wafer W 3  is mounted onto the wafer holder, and is suctioned by the vacuum chuck which is not shown. In this case, because the vertical movement pin maintains the state of moving upward by a predetermined amount, wafer loading can be performed within a short period of time than when the vertical movement pin is housed inside the wafer holder.  FIG. 15  shows a state where the new wafer W 3  which has not yet undergone exposure is loaded on wafer table WTB 1 . 
     Meanwhile, concurrently with the moving of wafer stage WST 1  to loading position LP and the loading of wafer W 3 , wafer stage WST 2  moves toward an exposure starting position of wafer W 2 , namely, an acceleration starting position for exposure of the first shot area, as shown by two outlined arrows in  FIG. 15 , while maintaining the proximity or contact state of measurement table MTB and wafer table WTB 2 . Prior to beginning this movement to the acceleration starting position, as shown in  FIG. 15 , in a state where measurement plate  30  of wafer stages WST 2  is at a position placed directly under projection optical system PL, main controller  20  stops both stages WST 2  and MST and performs the second half processing of BCHK and the second half processing of focus calibration, as necessary. 
     Here, the second half processing of BCHK refers to a processing in which projection images (aerial images) of a pair of measurement marks on reticle R (or a mark plate which is not shown on reticle stage RST) projected by projection optical system PL are measured using aerial image measurement devices  45   1  and  45   2  previously described that include measurement plate  30 . In this case, similar to the method disclosed in, for example, U.S. Patent Application Publication No. 2002/0041377 and the like, by an aerial image measurement operation of a slit scan method using the pair of aerial image measurement slit patterns SL, the aerial images of the pair of measurement marks are each measured, and the measurement results (the aerial image intensity corresponding to the XY position of wafer table WTB 2 ) are stored in memory. 
     Further, the second half processing of focus calibration refers to a processing of measuring the aerial images of the measurement marks on reticle R by a slit scan method using aerial image measurement devices  45   1  and  45   2  while controlling the position (Z position) of measurement plate  30  (wafer table WTB 2 ) in the optical axis direction of projection optical system PL using surface position information measured by the pair of XZ heads  65 X 3  and  64 X 3  that measure the surface position information on the ends on one side and the other side in the X-axis direction of wafer table WTB 2 , and measuring the best focus position of projection optical system PL based on the measurement results. 
     On this processing, because liquid immersion area  14  is formed in between projection optical system PL and measurement plate  30  (wafer table WTB), the measurement of the aerial images described above is performed via projection optical system PL and liquid Lq. Further, because measurement plate  30  and the like of aerial image measurement devices  45   1  and  45   2  are mounted on wafer stage WST 2  (wafer table WTB 2 ), and the photodetection element and the like are mounted on measurement stage MST, the measurement of the aerial images described above is performed while wafer stage WST and measurement stage MST keeping a contact or proximity state. 
     According to the measurement described above, measurement values of the pair of XZ heads  65 X 3  and  64 X 3  in a state where the center line of wafer table WTB 2  coincides with reference axis LV (that is, surface position information on the ends on one side and the other side in the X-axis direction of wafer table WTB 2 ) is obtained. Such measurement values correspond to the best focus position of projection optical system PL. 
     After the second half processing of BCHK and the second half processing of focus calibration described above have been performed, main controller  20  calculates the baseline of alignment detection system ALG, based on results of the first half processing of BCHK (which will be described later on) and results of the second half processing of BCHK. Further, along with this, based on a relation between measurement values of a pair of XZ heads  68 X 3  and  67 X 3  in a state where the center line of wafer table WTB 2  coincides with reference axis LV (surface position information on the ends on one side and the other side in the X-axis direction of wafer table WTB) obtained in the first half processing of focus calibration (which will be described later on) and detection results at the detection point on the surface of measurement plate  30  (surface position information) of the AF system ( 90   a ,  90   b ), and based on measurement values of the pair of XZ heads  65 X 3  and  64 X 3  in a state where the center line of wafer table WTB 2  coincides with reference axis LV (that is, surface position information on the ends on one side and the other side in the X-axis direction of wafer table WTB), which corresponds to the best focus position of projection optical system PL, obtained in the second half processing of focus calibration described above, main controller  20  obtains the offset at the detection point of the AF system ( 90   a ,  90   b ), and adjusts the detection origin of the AF system, for example, using the optical method so that the offset becomes zero. 
     In this case, from the viewpoint of improving the throughput, only one of the second half processing of BCHK and the second half processing of focus calibration described above may be performed, or the operation can go on to the next processing without performing both of the processing. As a matter of course, in the case when the second half processing of BCHK is not performed, the first half processing of BCHK previously described does not have to be performed. 
     When the operation so far has been completed, main controller  20 , as shown in  FIG. 16 , drives measurement stage MST in the −X direction and also in the +Y direction, and releases the contact or proximity state of both stages WST 2  and MST. 
     Then, main controller  20  performs exposure by a step-and-scan method, and transfers the reticle pattern onto the new wafer W 2 . This exposure operation is performed by main controller  20  repeating a movement between shots in which wafer stage WST is moved to a scanning starting position (acceleration starting position) for exposure of each shot area on wafer W, and scanning exposure in which the pattern formed on reticle R is transferred by a scanning exposure method to each shot area, based on the results of wafer alignment (EGA) (the array coordinates of all the shot areas on the wafer) performed in advance, the latest baseline of alignment detection system ALG and the like. Incidentally, the exposure operation described above is performed in a state where liquid (water) Lq is held between tip lens  191  and wafer W. 
     Further, in the present embodiment, as an example, the first shot area which is to be exposed first is decided to be the shot area positioned at the +Y edge of the −X side half of wafer W 2 , and therefore, first of all, wafer stage WST is moved in the +X direction and also the +Y direction, so as to be moved to the acceleration starting position. 
     And, while moving wafer stage WST 2  along the path shown by a black arrow in  FIG. 16 , exposure is performed in the order from the shot area on the +Y side to the shot area on the −Y side on the −X side half of wafer W 2 . 
     Concurrently with the exposure of the −X side half of wafer W 2 , on the wafer stage WST 1  side, a series of measurement operations which are described below is performed, following the loading operation of wafer W 3  previously described. 
     First of all, when wafer stage WST 1  is at loading position LP, the first half processing of baseline measurement (BCHK) of alignment detection system ALG is performed. Here, the first half processing of BCHK means the processing as below. That is, main controller  20  detects (observes) fiducial mark FM located in the center of measurement plate  30  described previously using alignment detection system ALG, and associates the detection results of alignment detection system ALG with the measurement values of the fine movement stage position measurement system  110 B at the time of detection and stores the associated information in memory. In the present embodiment, the first half processing of BCHK may be performed at least partially concurrently with the loading operation of wafer W described previously. 
     Following the first half processing of BCHK, when wafer stage WST 1  is at loading position LP, the first half processing of focus calibration is performed. 
     That is, while main controller  20  detects surface position information (Z position information of scales  39   1  and  39   2 ) at the edge on one side and the other side in the X-axis direction of wafer table WTB 1  detected by the pair of XZ heads  68 X 3  and  67 X 3  of the second top side encoder system  80 B, main controller  20  detects surface position information of the surface of measurement plate  30  previously described, using the AF system ( 90   a ,  90   b ), with a reference plane obtained from such information serving as a reference. From this detection, a relation is obtained between measurement values (the surface position information at the edge on one side and the other side in the X-axis direction of wafer table WTB 1 ) of the pair of XZ heads  68 X 3  and  67 X 3  in a state where the center line of wafer table WTB 1  coincides with reference axis LV previously described, and the detection results (surface position information) at the detection point on the surface of measurement plate  30  of the AF system ( 90   a ,  90   b ). 
     Next, main controller  20  begins the focus mapping using four-spindle heads  67  and  68  of the second top side encoder system  80 B and the AF system ( 90   a ,  90   b ). 
     Now, the focus mapping performed in exposure apparatus  100  related to the present embodiment will be described. On this focus mapping, main controller  20  controls the position within the XY plane of wafer table WTB 1 , based on measurement values of the two four-spindle heads  67  and  68  of the second top side encoder system  80 B that face scales  39   1  and  39   2 , respectively. 
     And, in this state, main controller  20  repeats a high speed scanning of wafer stage WST 1  alternately in the −Y direction and the +Y direction with a step movement in the X-axis direction in between as shown by outlined arrows in  FIG. 16 , takes in position information in the X-axis, the Y-axis and the Z-axis directions of both ends in the X-axis direction (the pair of the second water-repellent plates  28   b ) of the wafer table WTB 1  surface (plate  28  surface) measured by each of the two four-spindle heads  67  and  68  during the high speed scanning, and position information (surface position information) in the Z-axis direction of the wafer W surface detected at the detection point detected by the AF system ( 90   a ,  90   b ), at a predetermined sampling interval, and associates such taken-in information with each other and then sequentially stores the information in a memory which is not shown. 
     Then, main controller  20  completes the sampling described above, and then converts the surface position information on the detection point of the AF system ( 90   a ,  90   b ) into data which uses as a reference the position information in the Z-axis direction measured by each of the two four-spindle heads  67  and  68  simultaneously taken in. 
     To describe this further in detail, surface position information at a predetermined point (corresponding to a point on substantially the same X-axis as the detection point of the AF system ( 90   a ,  90   b ): hereinafter, referring to this point as a left measurement point) on an area near the −X side edge of plate  28  (the second water repellent plate  28   b  where scale  39   2  is formed) is obtained, based on measurement values of the Z position by one of the four-spindle heads, four-spindle head  67 . Further, surface position information at a predetermined point (corresponding to a point on substantially the same X-axis as the detection point of the AF system ( 90   a ,  90   b ): hereinafter, referring to this point as a right measurement point) on an area near the +X side edge of plate  28  (the second water repellent plate  28   b  where scale  39   1  is formed) is obtained, based on measurement values of the Z position by the other four-spindle head  68 . Then, main controller  20  converts the surface position information at the detection point of the AF system ( 90   a ,  90   b ) into surface position data which uses a straight line formed by connecting the surface position of the left measurement point and the surface position of the right measurement point (hereinafter referred to as a table surface reference line) as a reference. Main controller  20  performs such a conversion on all of the information taken in at the time of sampling. 
     Now, in exposure apparatus  100  related to the present embodiment, concurrently with the measurement by the second top side encoder system  80 B described above, measurement of position information of wafer table WTB 1  (fine movement stage WFS) in the X-axis direction, the Y-axis direction, the Z-axis direction and the θy direction (and the θz direction) by the second back side encoder system  70 B can be performed. Therefore, at the same timing as when the position information in the X-axis, the Y-axis and the Z-axis directions of both ends in the X-axis direction of the wafer table WTB 1  surface (plate  28  surface) measured by each of the two four-spindle heads  67  and  68 , and the position information (surface position information) in the Z-axis direction of the wafer W surface detected at the detection point detected by the AF system ( 90   a ,  90   b ) are taken in, main controller  20  also takes in measurement values of the position in each of the directions described above (X, Y, Z, θy (and θz)) by the second back side encoder system  70 B. And, main controller  20  obtains a relation between data (Z, θy) of the table surface reference line that can be obtained from the measurement information of the second top side encoder system  80 B, and measurement information (Z, θy) of the second back side encoder system  70 B, which are simultaneously taken in. This allows the surface position data using the table surface reference line described above as a reference to be converted into surface position data using a reference line corresponding to the table surface reference line described above which is determined by the Z position and the θy rotation of wafer table WTB obtained by a rear surface measurement (hereinafter, referred to as a rear surface measurement reference line, for the sake of convenience). 
     By acquiring the conversion data described above in advance in the manner described above, for example, on exposure and the like, wafer table WTB 1  (or WTB 2 ) surface (a point on the second water-repellent plate  28   b  where scale  39   2  is formed, and a point on the second water-repellent plate  28   b  where scale  39   1  is formed) is measured by XZ heads  64 X and  65 X previously described, and a Z position and a tilt with respect to the XY plane (mainly θy rotation) of wafer table WTB 1  (or WTB 2 ) are calculated. By using this Z position and the tilt with respect to the XY plane of wafer table WTB 1  (or WTB 2 ) that have been calculated and the surface position data (surface position data using the table surface reference line as a reference) previously described, surface position control of wafer W becomes possible, without actually having to acquire the surface position information of the wafer W surface. Accordingly, because the AF system can be placed at a position away from projection optical system PL without any problems, the focus mapping of the present embodiment can be suitably applied, even in the exposure apparatus having a small working distance (a distance between projection optical system PL and wafer W at the time of exposure). 
     After the focus mapping described above has been completed, wafer alignment is performed, for example, by an EGA method. To be more specific, main controller  20  step-drives wafer stage WST 1  in the XY two-dimensional directions as shown by outlined arrows in  FIG. 17  while performing servo-control on the position of wafer table WTB, based on the measurement values of the second fine movement stage position measurement system  110 B, and at each stepping position, detects an alignment mark arranged in each shot area on the wafer using alignment detection system ALG, and associates the detection results of alignment detection system ALG with the measurement values of the second fine movement stage position measurement system  110 B at the time of detection and stores the associated information in memory which is not shown. 
     Then, main controller  20  performs statistical calculation by the EGA method disclosed in, for example, U.S. Pat. No. 4,780,617 using measurement values of the second fine movement stage position measurement system  110 B that correspond to the detection results of the plurality of alignment marks obtained in the manner described above, and calculates EGA parameters (X offset, Y offset, orthogonal degree, wafer rotation, wafer X scaling, wafer Y scaling and the like), and obtains array coordinates of all the shot areas of wafer W 2  based on the calculation results. Then, main controller  20  converts the array coordinates into coordinates which uses a position of fiducial mark FM as a reference. At this point in time, the exposure of the area on the −X side half of wafer W 2  is still being continued. 
     Incidentally, while, in the description above, the wafer alignment is performed after the focus mapping has been completed, this is not intended to be limiting, and the focus mapping can be performed after the wafer alignment has been completed, or the focus mapping and the wafer alignment can be performed at least partially concurrent. 
     Then, when the series of measurement operations are completed, main controller  20 , as shown by an outlined arrow in  FIG. 18 , drives wafer stage WST 1  holding wafer W 3  in the −X direction and the +Y direction toward a standby position that is symmetric to the standby position of wafer stage WST 2  shown in  FIG. 9  with respect to reference axis LV.  FIG. 19  shows a state where wafer stage WST 1  moves to the standby position and is waiting at the position. This standby position is substantially directly under the waiting position UP 3  of the wafer described previously, and on the way of moving to the standby position, the measurement system that measures the position of wafer stage WST 1  is switched from the second fine movement stage position measurement system  110 B to measurement system  80 D. 
     Concurrently with moving wafer stage WST 1  to the standby position described above and the waiting at the standby position thereafter, main controller  20  performs exposure of the area on the +X side half of wafer W 2  held on wafer table WTB 2  while moving wafer stage WST 2  along a path shown by a black arrow in each of  FIGS. 18 and 19 . 
     When wafer stage WST 1  is moved to the standby position, main controller  20  carries wafer W 1  to the delivery position to the wafer carrier system by driving the wafer in the −Y direction as shown by a black arrow in  FIG. 20 , after driving downward, by a predetermined amount, the second unloading slider that holds wafer W 1  that has undergone exposure above waiting position UP 2 . 
     As is obvious when comparing  FIGS. 20 and 9 , while wafer stage WST 1  and wafer stage WST 2  are switched and the standby position of wafer stage WST 1  is set to a position symmetric about reference axis LV to the standby position of wafer stage WST 2  in the state shown in  FIG. 20 , the progress of the processing of the two wafers W held on the two wafer stages WST 1  and WST 2  is the same. 
     After that, an operation similar to the described above is repeated by main controller  20 , while alternately using wafer stages WST 1  and WST 2 . 
     However, on this repetition, when the exposure of wafer W held by wafer stage WST 2  is completed, wafer stage WST 2  is driven in the −Y direction to be replaced with wafer stage WST 1 , after being driven in the +X direction. In this case, wafer stage WST 1  is driven in the +Y direction to be replaced with wafer stage WST 2 . 
     Then, after the replacement, wafer stage WST 2  is moved to unloading position UP 1 , and then the exposed wafer that has been unloaded from wafer stage WST 2  is made to wait at waiting position UP 3  on the −X side of unloading position UP 1 . Then, at the point when the loading of a new wafer onto wafer stage WST 2  and the series of measurement operations described previously are completed, and wafer stage WST 2  is moved to the standby position directly under waiting position UP 2 , the exposed wafer that has been waiting at waiting position UP 3  is carried along the path in the −Y direction to the delivery position to the wafer carrier system. 
     As described in detail so far, according to exposure apparatus  100  related to the present embodiment, for example, in the case when one of the wafer stages, wafer stage WST 1  (or WST 2 ) is at exposure station  200 , and the other of the wafer stages, wafer stage WST 2  (or WST 1 ) is at measurement station  300 , it becomes possible to perform the series of measurement previously described on wafer W held by wafer table WTB 2  (or WTB 1 ) in measurement station  300 , concurrently with exposing wafer W held by wafer table WTB 1  (or WTB 2 ) using illumination light IL via projection optical system PL and liquid Lq in exposure station  200 . Further, when exposure to wafer W held by wafer table WTB 1  (or WTB 2 ) is completed, delivery of liquid Lq (liquid immersion area  14 ) directly below projection optical system PL is performed between wafer table WTB 1  (or WTB 2 ) and measurement table MTB, and the liquid is held by projection optical system PL and measurement table MTB. It becomes possible to perform this delivery of liquid Lq immediately after exposure to wafer W held by wafer table WTB 1  (or WTB 2 ) has been completed. This eliminates the need of delivering liquid Lq supplied to directly below projection optical system PL from one of wafer tables WTB 1  or WTB 2  to the other. This also eliminates the need of moving wafer table WTB 1  (or WTB 2 ) a long way around, for example, as in the case when liquid Lq supplied to directly below projection optical system PL is delivered from one of wafer tables WTB 1  or WTB 2  to the other, when wafer table WTB 1  (or WTB 2 ) is returned to the measurement station  300  side for wafer exchange and the like. Further, according to exposure apparatus  100  related to the present embodiment, in a state where liquid Lq is held between projection optical system PL and measurement table MTB, main controller  20  drives wafer stages WST 1  and WST 2  via coarse movement stage driving systems  51 A and  51 B so as to replace, in the Y-axis direction, the position of wafer stage WST 1  (or WST 2 ) that includes wafer table WTB 1  (or WTB 2 ) holding wafer W that has undergone exposure and the position of wafer stage WST 2  (or WST 1 ) that includes wafer table WTB 2  (or WTB 1 ) holding wafer W that has undergone the series of measurement described previously. In this case, in order to replace the positions in the Y-axis direction, main controller  20  concurrently drives wafer stage WST 1  including wafer table WTB 1  and wafer stage WST 2  including wafer table WTB 2  along the respective movement paths that include paths in reverse directions to each other and parallel to the Y-axis direction (refer to  FIG. 12 ). In the present embodiment, such movement paths that include paths in directions reverse to each other and parallel to the Y-axis direction are employed, and before and after wafer stages WST 1  and WST 2  pass through the movement paths, main controller  20  moves wafer stages WST 1  and WST 2  from one of exposure station  200  and measurement station  300  to the other, using coarse movement stage driving systems  51 A and  51 B, respectively, so that in replacement of one of arm members  71   1  and  71   2  (that is, heads  73   a  to  73   c  and  75   a  to  75   c ) placed in the space of coarse movement stage WCS, the other of arm members  71   1  and  71   2  (that is, heads  73   a  to  73   c  and  75   a  to  75   c ) is placed (refer to, for example,  FIGS. 9 and 18 ). In this case, main controller  20  controls the drive of wafer stage WST 1  or WST 2  by coarse movement stage driving system  51 A or  51 B based on the position information of wafer stage WST 1  or WST 2  measured by measurement system  80 D, so that wafer stage WST 1  or WST 2  moves from an area (a middle area) in between exposure station  200  and measurement station  300  to exposure station  200  (or measurement station  300 ). Further, wafer stage WST 1  and wafer stage WST 2  are moved from one of exposure station  200  and measurement station  300  to the other through the movement paths different from each other within the middle area described previously, and in the present embodiment, the positions of the different movement paths are different in the X direction, that is, the different movement paths are set apart on one edge side and the other edge side in the X direction on base board  12 . In the present embodiment, because the tube carrier is connected to wafer stage WST 1  from the −X direction and connected to wafer stage WST 2  from the +X direction, the movement path of wafer stage WST 1  is set on the −X side of projection optical system PL in the X direction and the movement path of wafer stage WST 2  is set on the +X side of projection optical system PL in the X direction. 
     Further, main controller  20  can perform at least one of an uneven illuminance measurement, an aerial image measurement, a wavefront aberration measurement and a dose measurement, using at least one of the measurement members that measurement table MTB has, namely, illuminance irregularity sensor  95 , aerial image measuring device  96 , wavefront aberration measuring device  97 , and illuminance monitor  98  that are previously described, in a part of a period after the exposure of wafer W held by one of wafer stages WST 1  or WST 2  has been completed until the exposure of wafer W held by the other of wafer stages WST 1  or WST 2  begins, including, for example, the time described above of replacing the position in the Y-axis direction of one of wafer stages WST 1  or WST 2  holding wafer W which has been exposed and the position in the Y-axis direction of the other of wafer stages WST 1  or WST 2  holding wafer W on which the series of measurements has been performed. This makes it possible to perform measurement related to exposure when necessary, without reducing the throughput. 
     In the present embodiment, the movement paths of wafer stages WST 1  and WST 2  further include paths in which wafer stages WST 1  and WST 2  are driven in directions reverse to each other in the X-axis direction (refer to  FIG. 13 ). 
     Accordingly, the throughput can be improved, and the apparatus can also be downsized. 
     According to exposure apparatus  100  related to the present embodiment, the first fine movement stage position measurement system  110 A, which measures the position of wafer table WTB 1  (or WTB 2 ), i.e. fine movement stage WFS, held movable in the directions of six degrees of freedom by coarse movement stage WCS when wafer stage WST 1  (or WST 2 ) is at exposure station  200 , is equipped with the first back side encoder system  70 A which irradiates a measurement beam from below on grating RG provided on the rear surface (surface on the −Z side) of wafer table WTB 1  (or WTB 2 ), receives the light (reflected and diffracted light) of the measurement beam from grating RG, and measures the position information of wafer table WTB 1  (or WTB 2 ) in the directions of six degrees of freedom, when wafer table WTB 1  (or WTB 2 ) moves in a predetermined range within exposure station  200  (a range within exposure station  200  that includes at least a range where wafer table WTB 1  (or WTB 2 ) moves for exposure of wafer W held by wafer table WTB 1  (or WTB 2 )), and is also equipped with the first top side encoder system  80 A which has head sections  62 A and  62 C provided at main frame BD, and irradiates a measurement beam on the pair of scales  39   1  and  39   2  (two-dimensional gratings) provided on wafer table WTB 1  (or WTB 2 ) from head sections  62 A and  62 C, receives the light (reflected and diffracted light) of the measurement beam from scales  39   1  and  39   2  (two-dimensional gratings), and can measure the position information of wafer table WTB 1  (or WTB 2 ) in the directions of six degrees of freedom, concurrently with the measurement of the position information by the first back side encoder system  70 A, when wafer table WTB 1  (or WTB 2 ) moves in the predetermined range described above within exposure station  200 . And, when wafer table WTB 1  (or WTB 2 ) moves in the predetermined range described above within exposure station  200 , such as, for example, at the time of exposure, main controller  20  drives wafer table WTB 1  (or WTB 2 ) based on the position information having higher reliability, out of the position information according to the first back side encoder system  70 A and the position information according to the first top side encoder system  80 A. 
     Further, according to exposure apparatus  100  related to the present embodiment, the second fine movement stage position measurement system  110 B, which measures the position of wafer table WTB 1  (or WTB 2 ), i.e. fine movement stage WFS, held movable in the directions of six degrees of freedom by coarse movement stage WCS when wafer stage WST 1  (or WST 2 ) is at measurement station  300 , is equipped with the second back side encoder system  70 B which irradiates a measurement beam from below on grating RG provided on the rear surface (surface on the −Z side) of wafer table WTB 1  (or WTB 2 ), receives light from grating RG (reflection diffraction light) of the measurement beam, and measures the position information of wafer table WTB 1  (or WTB 2 ) in the directions of six degrees of freedom, when wafer table WTB 1  (or WTB 2 ) moves in a predetermined range within measurement station  300  (a range within measurement station  300  including at least a range where wafer table WTB 1  (or WTB 2 ) moves for the series of measurement processing previously described, such as, for example, a range in measurement station  300  corresponding to the predetermined range previously described in exposure station  200 ), and is also equipped with the second top side encoder system  80 B which has head sections  62 F and  62 E provided at main frame BD, and irradiates a measurement beam on the pair of scales  39   1  and  39   2  (two-dimensional gratings) on wafer table WTB 1  (or WTB 2 ) from head sections  62 F and  62 E, receives light (reflection diffraction light) from scales  39   1  and  39   2  (two-dimensional gratings) of the measurement beam, and can measure the position information of wafer table WTB 1  (or WTB 2 ) in the directions of six degrees of freedom concurrently with the measurement of the position information by the second back side encoder system  70 B, when wafer table WTB 1  (or WTB 2 ) moves in the predetermined range described above in measurement station  300 . And, when wafer table WTB 1  (or WTB 2 ) moves in the predetermined range described above within measurement station  300 , such as, for example, at the time of alignment, main controller  20  servo-drives wafer table WTB 1  (or WTB 2 ) based on the position information having higher reliability, out of the position information according to the second back side encoder system  70 B and the position information according to the second top side encoder system  80 B. 
     Further, because unloading position LP 1  is set between the exposure position and the alignment position, to be more specific, at the position to which wafer stage WST 1  or WST 2  that holds wafer W that has been exposed is driven along the movement path in the −Y direction and then driven in the X-axis direction, the wafer which has been exposed can be unloaded from wafer table WTB 1  (or WTB 2 ) in a short time after exposure has been completed, and then wafer table WTB 1  (or WTB 2 ) can return to loading position LP. Further, after exposure has been completed, wafer table WTB 1  (or WTB 2 ) after having delivered liquid immersion area  14  (liquid Lq) to measurement table MTB, returns to unloading position LP 1  and then to loading position LP, without coming into contact with the liquid. Accordingly, the movement of wafer table WTB 1  (or WTB 2 ) at this point in time can be performed at a high speed and with high acceleration. Furthermore, because loading position LP is set at the position where the first half processing of BCHK of alignment detection system ALG is performed, the series of measurement processing including the first half processing of BCHK of alignment detection system ALG can be started at least partially concurrent with the loading of a wafer onto wafer table WTB 1  (or WTB 2 ), or immediately after the loading. Further, because this is measurement processing is performed without wafer table WTB 1  (or WTB 2 ) being in contact with the liquid, the processing can be performed while moving wafer table WTB 1  (or WTB 2 ) at a high speed and with high acceleration. 
     Furthermore, because, as the order of exposure of the plurality of shot areas on wafer W, the shot areas are exposed in the order from the −Y side to the +Y side on the +X side half (or the −X side half) after the shot areas have been exposed in the order from the +Y side to the −Y side on the −X side half (or the +X side half), wafer table WTB 1  (or WTB 2 ) is located at a position closest to unloading position LP 1  at the point when the exposure has been completed. Accordingly, after the exposure has been completed, wafer table WTB 1  (or WTB 2 ) can be moved to unloading position LP 1  in the shortest time. 
     As is obvious from the description so far, according to exposure apparatus  100  related to the present embodiment, exposure with high resolution is performed, with good overlay accuracy, by liquid immersion exposure to wafer W in a step-and-scan method, based on the highly precise results of the alignment and the focus mapping. Further, even if wafer W subject to exposure, for example, is a 450 mm wafer or the like, a high throughput can be maintained. To be specific, in exposure apparatus  100 , it is possible to achieve exposure processing to a 450 mm wafer, with equal or higher throughput to/than the exposure processing to a 300 mm wafer using a liquid immersion scanner as disclosed in U.S. Patent Application Publication No. 2008/0088843 and the like previously described. 
     Incidentally, in the embodiment described above, as an example of controlling the position of wafer table WTB 1  (WTB 2 ) in exposure station  200 , by using together the first back side encoder system  70 A and the first top side encoder system  80 A, and using measurement information having higher reliability out of measurement information of theses encoder systems, the measurement information by the first top side encoder system  80 A is used for the θx, the θy and the θz directions, and the measurement information by the first back side encoder system  70 A is used for the remaining directions, i.e. the X-axis, the Y-axis and the Z-axis directions, but this is merely an example. 
     For example, in an exposure apparatus to cope with a 450 mm wafer, because the length of measurement arm  71 A (arm member  71   1 ), with a cantilevered supported structure, of the first back side encoder system  70 A will become 500 mm or more in view of the size of the wafer table, the influence of background vibration (vibration of body) becomes large, for example, in a band of around 100 Hz to 400 Hz. In contrast, regarding the first top side encoder system  80 A, influence by vibration of the body is small, and it can be considered that measurement deception is small except for the extremely low frequency band. Therefore, focusing on these points, out of the measurement information of the first back side encoder system  70 A and measurement information of the first top side encoder system  80 A, the measurement information having higher reliability can be selectively used in the frequency band of the output signals. In this case, for example, the output of the first back side encoder system  70 A and the output of the first top side encoder system  80 A can be selectively used (switched) by using a low pass filter and a high pass filter that have the same cutoff frequency, or not limited to this, and for example, without using the filters, a hybrid position signal that is obtained by weighting the output signal of the top side encoder system and the output signal of the back side encoder system and adding both can be used. Further, the top side encoder system and the back side encoder system can be used separately or used together depending on other factors than the vibration. 
     Besides this, in the case when it is obvious that reliability is higher for measurement information (position information) according to the first back side encoder system  70 A or the first top side encoder system  80 A as for predetermined operations which involve movement of wafer table WTB 1  or WTB 2 , such position information having higher reliability can be used for position control of wafer table WTB 1  or WTB 2  during such operations. For example, in the first fine movement stage position measurement system  110 A, only the first back side encoder system  70 A may be used, for example, during scanning exposure. 
     In any case, according to the present embodiment, because position measurement of wafer table WTB 1  or WTB 2  is possible concurrently by the first back side encoder system  70 A and the first top side encoder system  80 A, various usages, such as using only one encoder system, or using both of the systems or the like, become possible depending on the good and bad points of these encoder systems. 
     Further, in the embodiment described above, a method similar to the one described above can be employed in the second fine movement stage position measurement system  110 B, for the method of selecting position information having higher reliability from measurement information (position information) according to the second back side encoder system  70 B and the second top side encoder system  80 B. 
     Further, while, in the embodiment described above, the first fine movement stage position measurement system  110 A is equipped with the first top side encoder system  80 A in addition to the first back side encoder system  70 A, this is not intended to be limiting, and the measurement system to measure the position of wafer table WTB 1  or WTB 2  in exposure station  200  can be only the first back side encoder system  70 A, or instead of the first top side encoder system  80 A, another encoder system having a different structure or an interferometer system or the like can be used in combination with the first back side encoder system  70 A. In the case of using only the first back side encoder system  70 A, it is desirable to perform calibration necessary for securing a long-term stability in the θx, the θy and the θz directions or the directions of six degrees of freedom of the coordinate system of back side encoder system  70 A. 
     Further, while, in the embodiment described above, the second fine movement stage position measurement system  110 B is equipped with the second back side encoder system  70 B and the second top side encoder system  80 B, this is not intended to be limiting, and the measurement system to measure the position of wafer table WTB 1  or WTB 2  in measurement station  300  can be only the second back side encoder system  70 B, or instead of the second top side encoder system  80 B, another encoder system having a different structure or an interferometer system or the like may be used in combination with the second back side encoder system  70 B. In the case of using only the second back side encoder system  70 B, it is desirable to perform calibration necessary for securing a long-term stability in the θx, the θy and the θz directions or the directions of six degrees of freedom of the coordinate system of back side encoder system  70 B. 
     Further, while, in the embodiment described above, exposure coordinate setting measurement system  34  and measurement coordinate setting measurement system  35  are each equipped with the Z sensors and the pair of imaging sensors that detect the position of the marks on the wafer table in the X and the Y two-dimensional directions, this is not intended to be limiting, and for example, instead of the imaging sensors, an absolute encoder which can measure the absolute position of the wafer table in the XY two-dimensional directions can be provided. 
     Further, while, in the embodiment described above, unloading position UP 1  is set in between exposure station  200  and measurement station  300 , this is not intended to be limiting, and the unloading position may be set in the vicinity of loading position LP, as in an exposure apparatus related to a modified example to be described next. 
     Modified Example 
       FIG. 21  shows a state of a moment during concurrent processing operations of the exposure apparatus related to a modified example.  FIG. 21  corresponds to a state of  FIG. 14  related to the embodiment described previously. As can seen from  FIG. 21 , in the exposure apparatus related to this modified example, unloading position UP and loading position LP are both set in the vicinity of the measurement arm. To be more specific, when assuming loading position LP of the exposure apparatus related to the embodiment described previously as a reference, loading position LP is set at a position a predetermined distance shifted to the +X side, and unloading position UP is set at a position a predetermined distance shifted to the −X side. And, waiting positions for the wafer such as waiting positions UP 2  and UP 3  described previously are not provided. Further, in the exposure apparatus related to the modified example, measurement coordinate setting measurement system  35  (imaging sensors  36   c  and  36   d  and Z sensors  38   d  to  38   f ) is placed on the +Y side of head sections  62 F and  62 E. The structures of the other parts and the like are similar to those of exposure apparatus  100  related to the embodiment described previously. 
     Now, of a series of concurrent processing operations using wafer stages WST 1  and WST 2  and measurement stage MST in the exposure apparatus related to this modified example, a part of operations including a wafer exchange operation will be described, based on  FIGS. 21 to 24 . 
     The concurrent processing using wafer stages WST 1  and WST 2  and measurement stage MST is performed in the procedure similar to that of the embodiment described previously, and when wafer stage WST 2  moves to the position shown in  FIG. 21 , main controller  20  switches a position measurement system used in position control of wafer table WTB 2  (wafer stage WST 2 ) temporarily to the third fine movement stage position measurement system  110 C from measurement system  80 D, similarly to the above-described manner. Afterwards, control of the position of wafer table WTB 2  is performed based on the measurement values according to the third fine movement stage position measurement system  110 C. Further, in a state where wafer stage WST 2  has moved to the position shown in  FIG. 21 , wafer table WTB 2  is in a state in contact with or proximity to measurement table MTB in the Y-axis direction (scrum state), for delivery of the liquid immersion area. 
     Next, main controller  20  drives wafer stage WST 2  and measurement stage MST in the +Y direction as is shown by two outlined arrows pointing upward in  FIG. 21 , while maintaining the contact or proximity state of wafer table WTB 2  and measurement table MTB. By this drive, liquid immersion area  14  (liquid Lq) formed below projection unit PU is moved (delivered) from measurement table MTB onto wafer table WTB 2 , and liquid immersion area  14  (liquid Lq) is to be held by projection optical system PL and wafer table WTB 2  (refer to  FIG. 23 ). 
     At the point when the delivery of liquid immersion area  14  described above has been completed, measurement arm  71 A is inserted into a space of wafer stage WST 2 , and the rear surface (grating RG) of wafer table WTB 2  faces heads  73   a  to  73   c  of measurement arm  71 A, and head sections  62 A and  62 C face scale  39   1  and  39   2  (refer to  FIG. 23 ). That is, the position of wafer table WTB 2  can be measured by the third fine movement stage position measurement system  110 C, as well as by the first fine movement stage position measurement system  110 A. Therefore, similarly to the above-described manner, main controller  20  performs origin return of the first back side encoder system  70 A and the first top side encoder system  80 A based on the position coordinates in the directions of six degrees of freedom of wafer table WTB 2  measured by the third fine movement stage position measurement system  110 C. In the manner described above, return of the exposure-time coordinate system which controls the position of wafer table WTB 2  that moves within exposure station  200  is performed. 
     After the return of the exposure-time coordinate system described above, main controller  20  controls the position of wafer table WTB 2 , based on the position information having higher reliability out of the position information of the first back side encoder system  70 A and the position information of the first top side encoder system  80 A. 
     Concurrently with the drive in the +Y direction of wafer stage WST 2  and measurement stage MST for the delivery of liquid immersion area  14  described above, main controller  20  drives wafer stage WST 1  toward unloading position UP (and loading position LP), as shown by an outlined arrow pointing downward in  FIG. 21 . Halfway along this drive, position measurement of wafer stage WST 1  (wafer table WTB 1 ) by measurement system  80 D can no longer be performed. Therefore, before wafer stage WST 1  falls out of the measurement range by measurement system  80 D, for example, at the point when wafer stage WST 1  reaches the position shown in  FIG. 22 , main controller  20  switches the position measurement system used for position control of wafer table WTB 1  (wafer stage WST 1 ) from measurement system  80 D previously described to the second fine movement stage position measurement system  110 B. That is, at the point when wafer stage WST 1  has reached the position shown in  FIG. 22 , measurement arm  71 B is inserted into a space of wafer stage WST 1 , and the rear surface (grating RG) of wafer table WTB 1  faces heads  75   a  to  75   c  of measurement arm  71 B, and head sections  62 F and  62 E face scales  39   1  and  39   2 . Further, at this point in time, measurement of the absolute position in the directions of six degrees of freedom of wafer table WTB 1  by measurement coordinate setting measurement system  35  is possible. Therefore, main controller  20  simultaneously measures the position in the directions of six degrees of freedom of wafer table WTB 1 , using measurement coordinate setting measurement system  35  and the second fine movement stage position measurement system  110 B. And, similarly to the previously-described manner, main controller  20  re-sets the measurement values of the second back side encoder system  70 B and the second top side encoder system  80 B of the second fine movement stage position measurement system  110 B, based on the absolute position of wafer table WTB 1  measured by measurement coordinate setting measurement system  35 , so as to perform origin return of the second back side encoder system  70 B and the second top side encoder system  80 B. In the manner described above, return of the measurement-time coordinate system which controls the position of wafer table WTB 1  that moves within measurement station  300  is performed. 
     Measurement coordinate setting measurement system  35  can measure the absolute position in the directions of six degrees of freedom of wafer table WTB 1 , and therefore, the switching from measurement system  80 D to the second fine movement stage position measurement system  110 B described above, namely, the return of the measurement-time coordinate system described above, can be performed within a short time. 
     After the return of the measurement-time coordinate system described above, main controller  20  drives wafer stage WST 1  in the −Y direction and also in the −X direction as shown by an outlined arrow in  FIG. 22 , and sets the position of wafer stage WST 1  at unloading position UP, while controlling the position of wafer table WTB 1  based on the position information having higher reliability out of the position information from the second back side encoder system  70 B and the position information from the second top side encoder system  80 B (refer to  FIG. 23 ). 
     At unloading position LP, wafer W 1  which has been exposed is unloaded from wafer stage WST 1  in the procedure described below. That is, after suction of wafer W 1  by a vacuum chuck which is not shown is released, by the vertical movement pin moving upward, wafer W 1  is lifted from the wafer holder. Then, the unloading arm made up of a robot arm and the like which is not shown is inserted between wafer W 1  and the holder, and by the unloading arm moving upward by a predetermined amount, wafer W 1  is delivered from the vertical movement pin to the unloading arm. Then, the unloading arm carries out the wafer to a delivery position to an external carrier system, as is shown by the black arrow in  FIG. 23 . In this case, the vertical movement pin maintains a state of moving upward by a predetermined amount in preparation for loading the next wafer. 
     Next, main controller  20  drives wafer stage WST 1  in the +X direction by a predetermined amount as is shown by an outlined arrow in  FIG. 24 , and sets the position of wafer stage WST 1  to loading position LP. At loading position LP, a new wafer W 3  before exposure (here, as an example, the wafer is to be a wafer in the middle of a lot (1 lot including 25 or 50 slices of wafers)) is loaded onto wafer table WTB 1  similarly to the previously-described manner.  FIG. 24  shows a state where the new wafer W 3  before exposure is loaded on wafer table WTB 1 . 
     Meanwhile, concurrently with the moving of wafer stage WST 1  to unloading position UP, the unloading of wafer W 1 , the moving of wafer stage WST 1  to loading position LP, and the loading of wafer W 3 , wafer stage WST 2  moves toward an exposure starting position of wafer W 2 , namely, an acceleration starting position for exposure of the first shot area, as shown by two outlined arrows each in  FIGS. 23 and 24 , while maintaining the contact or proximity state of measurement table MTB and wafer table WTB 2 . Prior to beginning this movement to the acceleration starting position, as shown in  FIG. 23 , in a state where measurement plate  30  of wafer stage WST 2  is at a position placed directly under projection optical system PL, main controller  20  stops both stages WST 2  and MST as necessary, and performs the second half processing of BCHK and the second half processing of focus calibration. 
     When the operations described so far are completed, main controller  20  drives measurement stage MST in the −X direction and the +Y direction, and after releasing the contact or proximity state of both stages WST 2  and MST, begins exposure of wafer W 2  similar to the previously-described exposure. 
     Concurrently with the exposure of wafer W 2  described above, main controller  20  performs a series of measurement processing. That is, main controller  20  drives wafer stage WST 1  where wafer W 3  is loaded by a predetermined amount in the −X direction, and sets the position of wafer stage WST 1  at a position where fiducial mark FM on measurement plate  30  is positioned in the field (detection area) of alignment detections system ALG. Then, after performing the first half processing of baseline measurement (BCHK) of alignment detection system ALG, main controller  20  performs the first half processing of focus calibration. After that, similarly to the embodiment described above, main controller  20  performs the focus mapping and the wafer alignment based on the EGA method. 
     Although the detailed description is omitted, the concurrent processing operations using wafer stages WST 1  and WST 2  similar to those in the embodiment described previously are performed subsequently by main controller  20 . 
     In the exposure apparatus related to the modified example described so far, although two wafer stages WST 1  and WST 2  are used, waiting positions UP 2  and UP 3  do not have to be provided and also the unloading system of the wafer can be structured by a single robot arm. Accordingly, especially, the structure of the unloading system of the wafer can be simplified. Incidentally, in the exposure apparatus related to the modified example, the unloading position and the loading position can be set at the same position, and in this case, it is preferable that the unloading position which also serves as the loading position is set at a position where fiducial mark FM on measurement plate  30  is positioned in the field (detection area) of alignment detection system ALG. 
     Further, in the embodiment and the modified example described above (hereinafter, referred to as the embodiment described above), a measurement system that measures position information of coarse movement stage WCS equipped in each of wafer stages WST 1  and WST 2 , and/or a measurement system that measures position information of slider section  60  and support section  62  of measurement stage MST, for example, an interferometer system and the like can be provided separately. In this case, a measurement system which measures relative position information between coarse movement stage WCS and fine movement stage WFS, and/or a measurement system which measures relative position information between slider section  60  and support section  62  of measurement stage MST and measurement table MTB can be provided. 
     Further, while, in the embodiment described above, the position information of wafer stage WST 1  or WST 2  in the area (the middle area) in between exposure station  200  and measurement station  300  is measured by measurement system  80 D (refer to  FIG. 6 ) having a plurality of Hall elements, this is not intended to be limiting, and measurement system  80 D can be structured by an interferometer system or an encoder system. Or, separately from measurement system  80 D, for example, similar to top side encoder systems  80 A and  80 B, or the third fine movement stage position measurement system  110 C and the like, an encoder system for middle area position measurement can be provided that has a plurality of heads provided outside wafer stage WST 1  or WST 2  and measures position information of wafer stage WST 1  or WST 2  by irradiating a measurement beam on each of scales  39   1  and  39   2  on wafer table WTB 1  or WTB 2  via the plurality of heads, when wafer stage WST 1  or WST 2  is located in the middle area. The plurality of heads of this encoder system are placed so as to cover the movement paths of wafer stages WST 1  and WST 2  in the middle area described previously. In this case, in order to move wafer stage WST 1  or WST 2  from the middle area to exposure station  200  or to measurement station  300 , main controller  20  can control the drive of wafer stage WST 1  or WST 2  by coarse movement stage driving system  51 A or  51 B, based on the position information of wafer stage WST 1  or WST 2  measured by measurement system  80 D and the position information of wafer stage WST 1  or WST 2  measured by the encoder system for middle area position measurement described above. 
     Incidentally, while, in the embodiment described above, the case has been described where the first and the second back side encoder systems  70 A and  70 B are equipped with measurement arms  71 A and  71 B having arm members  71   1  and  71   2 , respectively, in each of which only at least a part of the optical system of an encoder head is incorporated, this is not intended to be limiting, and for example, as long as a measurement beam can be irradiated from a section facing grating RG, for example, a light source or a photodetector and the like can be incorporated at the tip of the arm member. In this case, the optical fiber previously described does not have to be arranged inside of the arm member. Furthermore, the arm member can have any outer and sectional shape, or a damping member that suppresses vibration of a specific vibration frequency can be provided at its free end. Further, in the first and the second back side encoder systems  70 A and  70 B, the inside of arm members  71   1  and  71   2  do not necessarily have to be used even in the case when the light source and/or a detector are/is not provided in arm members  71   1  and  71   2 . 
     Further, while, in the embodiment described above, the case has been described as an example where the first and the second back side encoder systems  70 A and  70 B are each equipped with a three-dimensional head, an XZ head and a YZ head, it is a matter of course that the combination and placement of the heads are not limited to this. Further, the first and the second back side encoder systems  70 A and  70 B can each employ a head section (optical system) that is equipped with a Z head separately from an X head and/or a Y head. 
     In the embodiment described above, because grating RG is placed on the lower surface (rear surface) of fine movement stage WFS, fine movement stage WFS can be structured hollow to reduce its weight, and piping, wiring and the like can also be placed inside. That is because the measurement beam irradiated from the encoder head does not proceed inside fine movement stage WFS, and therefore fine movement stage WFS does not have to be a solid member through which light can be transmitted. However, this is not intended to be limiting, and in the case when fine movement stage WFS is a solid member through which light can be transmitted, the grating can be placed on the upper surface of the fine movement stage, that is, the surface facing the wafer, or the grating can be formed on the wafer holder which holds the wafer. In the latter case, even if the wafer holder expands during the exposure, or the loading position with respect to the fine movement stage deviates, such situation can be followed, and the position of the wafer holder (wafer) can be measured. 
     Further, the structures of the first to the third top side encoder systems  80 A to  80 C in the embodiment described above are not limited to the ones described in the embodiment above. For example, at least a part of the first to the third top side encoder systems  80 A to  80 C can employ an encoder system which has a structure, as disclosed in, for example, U.S. Patent Application Publication No. 2006/0227309 and the like, in which a plurality of encoder head sections (each encoder head section can be structured, for example, similar to the four-spindle head previously described) are provided on wafer table WTB, and facing these heads, a grating section (for example, a two-dimensional grating or a one-dimensional grating section placed two-dimensionally) can be placed external to wafer table WTB. In this case, the plurality of encoder head sections may be placed at four corners of wafer table WTB, or a pair of encoder head sections may be placed external to wafer table WTB, with wafer table WTB in between, on two diagonal lines intersecting at the center of wafer table WTB (the center of the wafer holder). Further, as the grating section, it is also possible that four grating plates on each of which a two-dimensional grating is formed are attached to one fixed member (such as a plate) and the fixed member is supported in a suspended manner by main frame BD using a support member including a flexure so that the four grating plates are placed in the periphery of projection optical system PL (or nozzle unit  32 ). 
     Incidentally, in the embodiment described above, in each of the back side encoder systems, the structure and the like of the head section are not limited to the above-described ones but arbitrary structure and the like may be employed. Further, in each of the top side encoder systems, arbitrary placement and number of the heads may be employed. 
     Incidentally, it is also possible that the placement (position) of the heads of the third top side encoder system  80 C is changed or at least one head is added, thereby allowing position information of measurement stage MST to be measured by the third top side encoder system  80 C during the scrum operation described previously. 
     Incidentally, while, in the embodiment described above, fine movement stage WFS is drivable in all of the directions of six degrees of freedom, this is not intended to be limiting, and fine movement stage WFS only has to be movable in at least within a two-dimensional plane parallel to the XY-plane. Further, fine movement stage driving systems  52 A and  52 B are not limited to the moving magnet type systems described above, and can also be moving coil type systems. Furthermore, fine movement stage WFS can be supported in contact by coarse movement stage WCS. Accordingly, the fine movement stage driving system which drives fine movement stage WFS with respect to coarse movement stage WCS, for example, can be a combination of a rotary motor and a ball spring (or a feed screw). 
     Incidentally, in the embodiment described above, all the measurement operations using a plurality of measurement members (sensors) of measurement stage MST need not be performed during replacement from one of wafer stage WST 1  and wafer stage WST 2  to the other, and for example, some of the plurality of measurements can be performed during the replacement from wafer stage WST 1  to wafer stage WST 2  and the remaining measurements can be performed during the replacement from wafer stage WST 2  to wafer stage WST 1 . 
     Further, in the embodiment described above, measurement stage MST does not necessarily have to have the various types of measurement members (sensors) described previously, and the measurement stage can be used only for maintaining the liquid immersion area under projection optical system PL instead of the wafer stage. In this case, at least a part of the various types of measurement members (sensors) can be provided at the wafer stage. 
     Further, in the embodiment described above, a device (also called a chuck unit) can be provided that is used to support in a non-contact manner a wafer before exposure above the loading position prior to loading the wafer onto wafer table WTB 1  or WTB 2 , and to load the wafer onto wafer table WTB 1  or WTB 2 . The chuck unit can be equipped with, for example, a Bernoulli chuck (or also called a float chuck), as a support member that supports the wafer from above in a non-contact manner. The chuck unit (Bernoulli chuck) may have, for example, only a carrying function, or in addition to the carrying function, may have at least one of a temperature adjusting function, a prealignment function and a bending correction function (flattening function), and the structure of the chuck unit (Bernoulli chuck) can be determined depending on the types and number of the functions to be added to the chuck unit (Bernoulli chuck), and as the structure to achieve four functions including the carrying function, the chuck unit (Bernoulli chuck) can have any structure as long as each of the functions can be achieved. Incidentally, not limited to the chuck which utilizes the Bernoulli effect like the Bernoulli chuck, a chuck that can support the wafer in a non-contact manner can be used. 
     Further, while, in the embodiment described above, the case has been described where the exposure apparatus employs the structure where wafer stage WST 1  and wafer stage WST 2  each equipped with fine movement stage WFS and coarse movement stage WCS that supports fine movement stage WFS are moved back and forth between measurement station  300  and exposure station  200 , this is not intended to be limiting, and it is also possible that the structure in which the two fine movement stages can be exchanged between the two coarse movement stages is added and the two fine movement stages are alternately made to move back and forth between measurement station  300  and exposure station  200 . Or, three or more fine movement stages can be used. It becomes possible to concurrently perform the exposure processing to a wafer on one of the fine movement stages WFS and the above-described measurement processing using the other of fine movement stages WFS. In this case, it is also possible that one of the two coarse movement stages is movable only in exposure station  200  and the other of the two coarse movement stages is movable only in measurement station  300 . 
     Incidentally, while, in the embodiment described above, the liquid immersion type exposure apparatus is described, the exposure apparatus is not limited to this, and can also be a dry type exposure apparatus which performs exposure of wafer W not via liquid (water). In such a case as well, for example, in the period after exposure of wafer W held by one wafer stage (WST 1  or WST 2 ) has been completed and the one wafer stage moves away from below projection optical system PL until exposure of wafer W held by the other wafer stage (WST 2  or WST 1 ) begins, main controller  20  can perform a measurement related to exposure in which illumination light IL via projection optical system PL is received via the light-receiving plane of each measuring device, using the measurement member that measurement table MTB has (that is, at least one of illuminance irregularity sensor  95 , aerial image measuring device  96 , wavefront aberration measuring device  97 , and illuminance monitor  98  previously described), that is, main controller  20  can perform at least one of an uneven illuminance measurement, an aerial image measurement, a wavefront aberration measurement and a dose measurement. This allows the measurement related to exposure to be performed as necessary, without reducing the throughput. 
     Incidentally, while, in the embodiment described above, the case has been described where the exposure apparatus is a scanning stepper, this is not intended to be limiting, and the embodiment described above can also be applied to a static type exposure apparatus such as a stepper. Further, the embodiment described above can also be applied to a reduction projection exposure apparatus which employs a step-and-stitch method where a shot area and a shot area are synthesized. 
     Further, the projection optical system in the exposure apparatus of the embodiment described above is not limited to a reduction system and can also be an equal magnifying or a magnifying system, and projection optical system PL is not limited to the refractive system, and can also be a reflection system or a catadioptric system, and the projection image can be either an inverted image or an upright image. 
     Further, illumination light IL is not limited to the ArF excimer laser beam (wavelength 193 nm), and can also be an ultraviolet light such as a KrF excimer laser beam (wavelength 248 nm), or a vacuum-ultraviolet light such as an F 2  laser beam (wavelength 157 nm). For example, as disclosed in U.S. Pat. No. 7,023,610, as the vacuum-ultraviolet light, a harmonic wave can also be used which is a single-wavelength laser beam in the infrared or visible range emitted by a DFB semiconductor laser or a fiber laser that is amplified by a fiber amplifier doped with, for example, erbium (or both erbium and ytterbium), and whose wavelength is converted into a vacuum-ultraviolet light using a nonlinear optical crystal. 
     Further, in the embodiment described above, it is a matter of course that illumination light IL of the exposure apparatus is not limited to light having a wavelength of 100 nm or over, and light having a wavelength less than 100 nm can also be used. For example, the embodiment described above can be applied to an EUV (Extreme Ultraviolet) exposure apparatus that uses an EUV light in a soft X-ray range (for example, a wavelength range of 5 to 15 nm). In addition, the embodiment descried above can also be applied to an exposure apparatus that uses charged particle beams such as an electron beam or an ion beam. 
     Further, while, in the embodiment described above, a light transmissive type mask (reticle) in which a predetermined light-shielding pattern (or a phase pattern or a light-attenuation pattern) is formed on a light-transmitting substrate is used, instead of this reticle, as disclosed in, for example, U.S. Pat. No. 6,778,257, an electron mask (which is also called a variable shaped mask, an active mask or an image generator, and includes, for example, a DMD (Digital Micro-mirror Device) that is a type of a non-emission type image display element (spatial light modulator) or the like) where a light-transmitting pattern, a reflection pattern, or an emission pattern is formed according to electronic data of the pattern that is to be exposed can also be used. In the case of using such a variable shaped mask, because the stage where the wafer or the glass plate and the like is mounted is scanned with respect to the variable shaped mask, by measuring the position of this stage using the first and the second fine movement stage position measurement systems  110 A and  110 B previously described, an effect equal to the embodiment described above can be obtained. 
     Further, as disclosed in, for example, PCT International Publication No. 2001/035168, the embodiment described above can also be applied to an exposure apparatus (lithography system) which forms a line-and-space pattern on wafer W by forming an interference fringe on wafer W. 
     Furthermore, as disclosed in, for example, U.S. Pat. No. 6,611,316, the embodiment described above can also be applied to an exposure apparatus that synthesizes two reticle patterns on a wafer via a projection optical system, and by performing scanning exposure once, performs double exposure of one shot area on the wafer almost simultaneously. 
     Incidentally, in the embodiment described above, the object where the pattern is to be formed (the object subject to exposure on which an energy beam is irradiated) is not limited to a wafer, and may be another object such as a glass plate, a ceramic substrate, a film member, or a mask blank and the like. 
     The usage of the exposure apparatus is not limited to the exposure apparatus used for producing semiconductor devices, and for example, the exposure apparatus can also be widely applied to an exposure apparatus for liquid crystal displays used to transfer a liquid crystal display device pattern on a square shaped glass plate, or an exposure apparatus used to manufacture an organic EL, a thin film magnetic head, an imaging device (such as a CCD), a micromachine, a DNA chip and the like. Further, the embodiment described above can also be applied not only to an exposure apparatus for producing microdevices such as semiconductor devices, but also to an exposure apparatus which transfers a circuit pattern on a glass substrate or a silicon wafer, in order to manufacture a reticle or a mask used in a light exposure apparatus, an EUV exposure apparatus, an X-ray exposure apparatus, and an electron beam exposure apparatus and the like. 
     Electronic devices such as semiconductor devices are manufactured through the following steps; a step where the function/performance design of the device is performed, a step where a reticle based on the design step is manufactured, a step where a wafer is manufactured from silicon materials, a lithography step where the pattern of a mask (reticle) is transferred onto the wafer by the exposure apparatus (pattern formation apparatus) related to the embodiment previously described and an exposure method corresponding thereto, a development step where the wafer that has been exposed is developed, an etching step where an exposed member of an area other than the area where the resist remains is removed by etching, a resist removing step where the resist that is no longer necessary when etching has been completed is removed, a device assembly step (including a dicing process, a bonding process, and a package process), an inspection step and the like. In this case, in the lithography step, because the device pattern is formed on the wafer by executing the exposure method previously described using the exposure apparatus in the embodiment described above, a highly integrated device can be produced with good productivity. 
     Further, the exposure apparatus (pattern forming apparatus) in the embodiment described above is manufactured by assembling various subsystems, which include the respective constituents that are recited in the claims of the present application, so as to keep predetermined mechanical accuracy, electrical accuracy and optical accuracy. In order to secure these various kinds of accuracy, before and after the assembly, adjustment to achieve the optical accuracy for various optical systems, adjustment to achieve the mechanical accuracy for various mechanical systems, and adjustment to achieve the electrical accuracy for various electric systems are performed. A process of assembling various subsystems into the exposure apparatus includes mechanical connection, wiring connection of electric circuits, piping connection of pressure circuits, and the like among various types of subsystems. Needless to say, an assembly process of individual subsystem is performed before the process of assembling the various subsystems into the exposure apparatus. When the process of assembling the various subsystems into the exposure apparatus is completed, a total adjustment is performed and various kinds of accuracy as the entire exposure apparatus are secured. Incidentally, the making of the exposure apparatus is preferably performed in a clean room where the temperature, the degree of cleanliness and the like are controlled. 
     Incidentally, the disclosures of all the publications, the PCT International Publications, the U.S. patent Application Publications and the U.S. patents that are cited in the description so far related to exposure apparatuses and the like are each incorporated herein by reference. 
     While the above-described embodiment of the present invention is the presently preferred embodiment thereof, those skilled in the art of lithography systems will readily recognize that numerous additions, modifications, and substitutions may be made to the above-described embodiment without departing from the spirit and scope thereof. It is intended that all such modifications, additions, and substitutions fall within the scope of the present invention, which is best defined by the claims appended below.