Exposure apparatus, exposure method, and method for producing device

An exposure apparatus fills an optical path space of an exposure light beam with a liquid, and exposes a substrate by irradiating the substrate with the exposure light beam via a projection optical system and the liquid. A first optical element of the projection optical system is provided with a removing device for removing foreign matters in a space inside of the concave surface portion. Immersion exposure is performed by permitting the exposure light beam to excellently reach an image plane via the projection optical system and the liquid.

TECHNICAL FIELD

The present invention relates to an exposure apparatus, an exposure method, and a method for producing a device, wherein a substrate is exposed through a liquid.

BACKGROUND ART

An exposure apparatus, which performs the projection exposure onto a photosensitive substrate with a pattern formed on a mask, is used in the photolithography step as one of the steps of producing microdevices such as semiconductor devices, liquid crystal display devices, and the like. The exposure apparatus includes a mask stage for supporting the mask and a substrate stage for supporting the substrate. The pattern of the mask is subjected to the projection exposure onto the substrate via a projection optical system while successively moving the mask stage and the substrate stage. In the microdevice production, it is required to realize a fine and minute pattern to be formed on the substrate in order to achieve a high density of the device. In order to respond to this requirement, it is demanded to realize a higher resolution of the exposure apparatus. A liquid immersion exposure apparatus, in which a liquid immersion area is formed by filling the space between the projection optical system and the substrate with a liquid to perform the exposure process through the liquid of the liquid immersion area, has been contrived as one of means to realize the high resolution, as disclosed in the patent literature 1.Patent Literature 1: the International Publication No. 99/49504.

DISCLOSURE OF THE INVENTION

Task to be Solved by the Invention

In the liquid immersion exposure apparatus, the higher the refractive index of the liquid for filling the optical path space for the exposure light beam therewith is, the more improved the resolution and the depth of focus are. Accordingly, it is demanded to realize a liquid immersion exposure apparatus based on the use of the liquid having the high refractive index as described above.

The present invention has been made taking the foregoing circumstances into consideration. A first object of the present invention is to provide an exposure apparatus, an exposure method, and a method for producing a device based on the use of the exposure apparatus and the exposure method, wherein it is possible to realize the liquid immersion exposure by a liquid having a high refractive index. A second object of the present invention is to provide an exposure apparatus, an exposure method, and a method for producing a device based on the use of the exposure apparatus and the exposure method, wherein an exposure light beam is successfully allowed to arrive at an image plane through a liquid.

Solution for the Task

In order to achieve the objects as described above, the present invention adopts the following constructions corresponding toFIGS. 1 to 12as illustrated in embodiments. However, parenthesized symbols affixed to respective elements merely exemplify the elements by way of example, with which it is not intended to limit the respective elements.

According to a first aspect of the present invention, there is provided an exposure apparatus (EX) which exposes a substrate (P) by radiating an exposure light beam (EL) onto the substrate (P) through a liquid (LQ); the exposure apparatus comprising a projection optical system (PL) which includes a plurality of optical elements, at least one (LS1) of the plurality of optical elements having a concave surface portion (2) making contact with the liquid; and a removing device (40) which removes a foreign matter in a space inside of the concave surface portion (2).

According to the first aspect of the present invention, at least one optical element for constructing the projection optical system has the concave surface portion which makes contact with the liquid. Therefore, the angle of incidence of the exposure light beam can be reduced at the interface between the liquid and the optical element, and the exposure light beam is successfully allowed to arrive at the object (substrate or substrate stage) arranged on the image plane of the projection optical system or in the vicinity thereof. Even when any foreign matter is present in the space inside of the concave surface portion of the optical element which makes contact with the liquid, the foreign matter is removed by the removing device. Therefore, it is possible to allow the exposure light beam to satisfactorily arrive at the image plane of the projection optical system or the position disposed in the vicinity thereof.

According to a second aspect of the present invention, there is provided an exposure apparatus (EX) which exposes a substrate (P) by radiating an exposure light beam (EL) onto the substrate (P) through a liquid (LQ); the exposure apparatus comprising a projection optical system (PL) which includes a plurality of optical elements (LS1to LS5) and which has a first optical element (LS1) included in the plurality of optical elements and disposed closest to an image plane of the projection optical system, the first optical element (LS1) having a concave surface portion (2) which makes contact with the liquid (LQ); wherein a refractive index of the liquid with respect to the exposure light beam is higher than a refractive index of the first optical element.

According to the second aspect of the present invention, the liquid is used, which has the refractive index higher than the refractive index of the first optical element disposed closest to the image plane of the projection optical system with respect to the exposure light beam. Accordingly, it is possible to greatly improve the resolution and the depth of focus. The first optical element has the concave surface portion which makes contact with the liquid. Therefore, it is possible to allow the exposure light beam to satisfactorily arrive at the image plane of the projection optical system or the position disposed in the vicinity thereof.

According to a third aspect of the present invention, there is provided a method for producing a device, comprising using the exposure apparatus (EX) as defined in any one of the aspects described above. According to the third aspect of the present invention, it is possible to provide the device having the desired performance.

According to a fourth aspect of the present invention, there is provided an exposure method for exposing a substrate by radiating an exposure light beam onto the substrate (P) via a liquid (LQ) and an optical element (LS1) having a concave surface portion (2) which makes contact with the liquid (LQ); the exposure method including removing a foreign matter from the liquid (LQ) in the concave surface portion (2) of the optical element; and exposing the substrate (P) by radiating the exposure light beam onto the substrate via the optical element (LS1) and the liquid (LQ). According to this exposure method, the surface of the optical element which makes contact with the liquid is the concave surface. Therefore, the light beam, which is inclined with respect to the optical axis of the optical element, successfully has the reduced angle of incidence (angle of incidence toward the liquid) at the interface between the liquid and the optical element. Therefore, even when the refractive index of the liquid is higher than the refractive index of the optical element, it is possible to allow the outermost beam of the light flux (convergent light flux) to come into the liquid as well.

According to a fifth aspect of the present invention, there is provided an exposure method for exposing a substrate (P) by radiating an exposure light beam (EL) onto the substrate (P) via a liquid (LQ) and an optical element (LS1) having a concave surface portion to make contact with the liquid; the exposure method including supplying the liquid (LQ) to a space between the substrate (P) and the concave surface portion (2) of the optical element (LS1), the liquid (LQ) having a refractive index higher than a refractive index of the optical element; and exposing the substrate by radiating the exposure light beam onto the substrate (P) via the optical element (LS1) and the liquid. According to this exposure method, the exposure is performed through the liquid having the refractive index higher than the refractive index of the optical element (LS1). Therefore, it is possible to increase the numerical aperture NA for the optical element and the light radiation system (projection optical system) including the optical element, and it is possible to improve the resolution and the depth of focus. The reflection of the exposure light beam at the interface between the liquid and the optical element, which tends to occur as the numerical aperture NA is increased, is suppressed by the concave surface portion provided at the portion of the optical element which makes contact with the liquid.

According to a sixth aspect of the present invention, there is provided a method for producing a device; including exposing a substrate by the exposure method as defined in the fourth or fifth aspect; developing the exposed substrate; and processing the developed substrate. According to this production method, it is possible to provide the high density device having the desired performance.

EFFECT OF THE INVENTION

According to the present invention, it is possible to allow the exposure light beam to satisfactorily arrive at the image plane or the position in the vicinity thereof. It is possible to perform the accurate exposure process, and it is possible to produce the device having the desired performance.

PARTS LIST

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be explained below with reference to the drawings. However, the present invention is not limited thereto.

First Embodiment

FIG. 1shows a schematic arrangement illustrating an exposure apparatus EX according to a first embodiment. With reference toFIG. 1, the exposure apparatus EX comprises a mask stage MST which is movable while holding a mask M, a substrate stage PST which is movable while holding a substrate P, an illumination optical system IL which illuminates, with an exposure light beam EL, the mask M held by the mask stage MST, a projection optical system PL which projects an image of a pattern of the mask M illuminated with the exposure light beam EL onto the substrate P held by the substrate stage PST, and a control unit CONT which integrally controls the operation of the entire exposure apparatus EX. A storage unit MRY, which stores various pieces of information in relation to the exposure process, is connected to the control unit CONT.

The exposure apparatus EX of this embodiment is a liquid immersion exposure apparatus to which the liquid immersion method is applied in order that the exposure wavelength is substantially shortened to improve the resolution and to substantially widen the depth of focus. The exposure apparatus EX is provided with a liquid immersion mechanism1which forms a liquid immersion area LR of the liquid LQ on the substrate P. The liquid immersion mechanism1includes a nozzle member70which is provided in the vicinity of the image plane of the projection optical system PL and which has a supply port18for supplying the liquid LQ and a recovery port28for recovering the liquid LQ, a liquid supply mechanism10which supplies the liquid LQ to the image plane side of the projection optical system PL via the supply port18provided for the nozzle member70, and a liquid recovery mechanism20which recovers the liquid LQ on the image plane side of the projection optical system PL via the recovery port28provided for the nozzle member70. The nozzle member70is formed in an annular form so that a first optical element LS1, which is included in a plurality of optical elements LS1to LS5for constructing the projection optical system PL and which is disposed closest to the image plane of the projection optical system PL, is surrounded over or above the substrate P (substrate stage PST).

The first optical element LS1of the projection optical system PL, which is disposed closest to the image plane of the projection optical system PL, has a concave surface portion2which makes contact with the liquid LQ of the liquid immersion area LR. The concave surface portion2is provided on the lower surface T1of the first optical element LS1opposed to the substrate P. The exposure apparatus EX further includes a removing unit40which removes any foreign matter in the space inside of the concave surface portion2of the first optical element LS1. The removing unit40includes a suction member42which has a suction port43for sucking the foreign matter and which is provided on the substrate stage PST that is movable on the image plane side of the projection optical system PL. The exposure apparatus EX further includes a detection unit50which detects whether or not the foreign matter is present in the space inside of the concave surface portion2. The detection unit50includes an image pickup device such as CCD, which is provided on the substrate stage PST.

The exposure apparatus EX forms the liquid immersion area LR locally on a part of the substrate P including a projection area AR of the projection optical system PL by the liquid LQ supplied from the liquid supply mechanism10at least during the period in which the pattern image of the mask M is transferred onto the substrate P, the liquid immersion area LR being larger than the projection area AR and smaller than the substrate P. Specifically, the exposure apparatus EX adopts the local liquid immersion system, wherein the optical path space, which is disposed between the first optical element LS1arranged closest to the image plane of the projection optical system PL and the surface of the substrate P arranged on the image plane side of the projection optical system PL, is filled with the liquid LQ. The liquid immersion area of the liquid LQ is formed on a part of the substrate P, and the exposure light beam EL, which is allowed to pass through the mask M, is radiated onto the substrate P via the liquid LQ and the projection optical system PL. Accordingly, the substrate P is subjected to the projection exposure with the pattern of the mask M. The control unit CONT locally forms the liquid immersion area LR of the liquid LQ on the substrate P such that a predetermined amount of the liquid LQ is supplied onto the substrate P by the liquid supply mechanism10, and a predetermined amount of the liquid LQ on the substrate P is recovered by the liquid recovery mechanism20.

The embodiment of the present invention will be explained as exemplified by a case of the use of the scanning type exposure apparatus (so-called scanning stepper) as the exposure apparatus EX in which the substrate P is exposed with the pattern formed on the mask M while synchronously moving the mask M and the substrate P in mutually different directions (opposite directions) in the scanning directions. In the following explanation, the X axis direction resides in the synchronous movement direction (scanning direction) for the mask M and the substrate P in the horizontal plane, the Y axis direction (non-scanning direction) resides in the direction which is perpendicular to the X axis direction in the horizontal plane, and the Z axis direction resides in the direction which is perpendicular to the X axis direction and the Y axis direction and which is coincident with the optical axis AX of the projection optical system PL. The directions of rotation (inclination) about the X axis, the Y axis, and the Z axis are designated as θX, θY, and θZ directions respectively. The term “substrate” referred to herein includes those obtained by coating a semiconductor wafer with a resist (photosensitive material), and the term “mask” includes a reticle formed with a device pattern to be subjected to the reduction projection onto the substrate.

The illumination optical system IL includes, for example, an exposure light source, an optical integrator which uniformizes the illuminance of the light flux radiated from the exposure light source, a condenser lens which collects the exposure light beam EL supplied from the optical integrator, a relay lens system, and a field diaphragm which sets the illumination area on the mask M illuminated with the exposure light beam EL. The predetermined illumination area on the mask M is illuminated with the exposure light beam EL having a uniform illuminance distribution by the illumination optical system IL. Those usable as the exposure light beam EL radiated from the illumination optical system IL include, for example, far ultraviolet light beams (DUV light beams) such as emission lines (g-ray, h-ray, i-ray) radiated, for example, from a mercury lamp, the KrF excimer laser beam (wavelength: 248 nm), and the like, and vacuum ultraviolet light beams (VUV light beams) such as the ArF excimer laser beam (wavelength: 193 nm), the F2laser beam (wavelength: 157 nm), and the like. In this embodiment, the ArF excimer laser beam is used.

The mask stage MST is movable while holding the mask M. The mask stage MST holds the mask M by means of the vacuum attraction (or the electrostatic attraction). The mask stage MST is two-dimensionally movable in the plane perpendicular to the optical axis AX of the projection optical system PL, i.e., in the XY plane, and it is finely rotatable in the θZ direction in a state in which the mask M is held, in accordance with the driving of a mask stage-driving unit MSTD including a linear motor controlled by the control unit CONT. A movement mirror81, which is movable together with the mask stage MST, is provided on the mask stage MST. A laser interferometer82is provided at a position opposed to the movement mirror81. The position in the two-dimensional direction and the angle of rotation in the θZ direction (including the angles of rotation in the θX and θY directions in some situations) of the mask M on the mask stage MST are measured in real-time by the laser interferometer82. The result of the measurement of the laser interferometer82is outputted to the control unit CONT. The control unit CONT drives the mask stage-driving unit MSTD on the basis of the result of the measurement obtained by the laser interferometer82to thereby control the position of the mask M held on the mask stage MST.

The projection optical system PL projects the pattern of the mask M onto the substrate P at a predetermined projection magnification β to perform the exposure. The projection optical system PL comprises a plurality of optical elements LS1to LS5. The optical elements LS1to LS5are supported by a barrel PK. In this embodiment, the projection optical system PL is the reduction system having the projection magnification β which is, for example, ¼, ⅕, or ⅛. The projection optical system PL may be any one of the 1× magnification system and the magnifying system. The projection optical system PL is the dioptric system including no catoptric element. However, the projection optical system PL may be the catadioptric system including dioptric and catoptric elements.

The projection optical system PL is provided with an image formation characteristic-adjusting unit LC as disclosed, for example, in Japanese Patent Application Laid-open Nos. 60-78454 and 11-195602. The image formation characteristic-adjusting unit LC is adjustable of the image formation characteristic such as the image plane position of the projection optical system PL by driving a specified optical element of the plurality of optical elements LS1to LS5included in the projection optical system PL and/or adjusting the pressure in the barrel PK.

The substrate stage PST has a substrate holder PH which holds the substrate P. The substrate holder PH is movable on the image plane side of the projection optical system PL. The substrate holder PH holds the substrate P, for example, by the vacuum attraction. A recess86is provided on the substrate stage PST. The substrate holder PH for holding the substrate P is arranged in the recess86. The upper surface87of the substrate stage PST other than the recess86is a flat surface (flat section) which has approximately the same height as that of (flush with) the surface of the substrate P held by the substrate holder PH.

The substrate stage PST is two-dimensionally movable in the XY plane on the base member BP, and it is finely rotatable in the θZ direction in a state in which the substrate P is held by the aid of the substrate holder PH, in accordance with the driving of the substrate stage-driving unit PSTD including a linear motor or the like controlled by the control unit CONT. Further, the substrate stage PST is also movable in the Z axis direction, the θX direction, and the θY direction. Therefore, the surface of the substrate P supported by the substrate stage PST is movable in the directions of six degrees of freedom in the X axis, Y axis, Z axis, θX, θY, and θZ directions. A movement mirror83, which is movable together with the substrate stage PST, is fixed to the side surface of the substrate stage PST. A laser interferometer84is provided at a position opposed to the movement mirror83. The position in the two-dimensional direction and the angle of rotation of the substrate P on the substrate stage PST are measured in real time by the laser interferometer84. The exposure apparatus EX is provided with a focus/leveling-detecting system (not shown) based on the oblique incidence system which detects the surface position information about the surface of the substrate P held by the substrate stage PST as disclosed, for example, in Japanese Patent Application Laid-open No. 8-37149. The focus/leveling-detecting system detects the surface position information about the surface of the substrate P (position information in the Z axis direction, and the information about the inclination in the θX and θY directions of the substrate P). A system based on an electrostatic capacity type sensor may be adopted for the focus/leveling-detecting system. The result of the measurement performed by the laser interferometer84is outputted to the control unit CONT. The result of the detection performed by the focus/leveling-detecting system is also outputted to the control unit CONT. The control unit CONT drives the substrate stage-driving unit PSTD on the basis of the detection result of the focus/leveling-detecting system to adjust and match the surface of the substrate P with respect to the image plane of the projection optical system PL by controlling the focus position (Z position) and the angle of inclination (θX, θY) of the substrate P. Further, the position is controlled in the X axis direction, the Y axis direction, and the θZ direction of the substrate P on the basis of the measurement result of the laser interferometer84.

Next, an explanation will be made about the liquid LQ for filling the optical path space for the exposure light beam EL therewith. In the following explanation, the refractive index of the liquid LQ and the refractive index of the first optical element LS1with respect to the exposure light beam EL (ArF laser beam, wavelength: 193 nm) will be simply referred to as “refractive index”. In this embodiment, the liquid supply mechanism10supplies the liquid LQ having the refractive index higher than the refractive index of the first optical element LS1which is disposed closest to the image plane of the projection optical system PL and which is included in the plurality of optical elements LS1to LS5for constructing the projection optical system PL. The optical path space, which is disposed between the first optical element LS1and the substrate P (or the substrate stage PST) arranged on the image plane side of the projection optical system PL, is filled with the liquid LQ having the high refractive index. In this embodiment, the first optical element LS1is formed of silica glass. The refractive index of the liquid LQ is higher than the refractive index of silica glass. In this case, the refractive index of silica glass is about 1.5, and the refractive index of the liquid LQ supplied from the liquid supply mechanism10is about 1.6. The first optical element LS1may be formed of calcium fluoride.

The ArF excimer laser beam as the exposure light beam EL is transmissive through silica glass which is the material for forming the first optical element LS1. Silica glass is the material having the large refractive index. Therefore, for example, it is possible to decrease the size (diameter) of the first optical element LS1. It is possible to realize compact sizes of the entire projection optical system PL and the entire exposure apparatus EX. For example, the optical elements LS2to LS5may be formed of calcium fluoride, and the optical element LS1may be formed of silica glass. Alternatively, the optical elements LS2to LS5may be formed of silica glass, and the optical element LS1may be formed of calcium fluoride. Further alternatively, all of the optical elements LS1to LS5may be formed of silica glass (or calcium fluoride).

FIG. 2shows a magnified sectional view illustrating those disposed in the vicinity of the first optical element LS1arranged closest to the image plane of the projection optical system PL. With reference toFIG. 2, the concave surface portion2is formed at the lower surface T1of the first optical element LS1opposed to the substrate P. The supply port18is provided on the lower surface70A of the nozzle member70opposed to the substrate P so that the supply port18surrounds the projection area AR of the projection optical system PL. The recovery port28is provided outside the supply port18with respect to the projection area AR on the lower surface70A of the nozzle member70. The recovery port28is formed to have an annular slit-shaped form on the lower surface70A of the nozzle member70. The space among the lower surface T1of the first optical element LS1, the lower surface70A of the nozzle member70, and the substrate P is filled with the liquid LQ of the liquid immersion area LR.

The optical path space, which is disposed on the side of the upper surface T2of the first optical element LS1, is filled with the gas (nitrogen). The optical path space, which is disposed on the side of the lower surface T1of the first optical element LS1, is filled with the liquid LQ. The upper surface T2of the first optical element LS1has a shape of convex curved surface to expand toward the object plane of the projection optical system PL (toward the mask). With this shape, all beams, which form the image on the surface of the substrate P (image plane), are allowed to come thereinto.

The lower surface T1of the first optical element LS1has the concave surface portion2which is recessed to make separation from the substrate P. The concave surface portion2has a curved shape. In the same manner as the shape of the upper surface T2, the lower surface T1has such a shape that all beams, which form the image on the surface of the substrate P, are allowed to come thereinto.

With reference toFIG. 2, the lower surface T1and the upper surface T2of the first optical element LS1are depicted to have spherical shapes having the same center of curvature. However, the respective curvatures and the curved shapes can be appropriately determined so that the projection optical system PL successfully obtains the desired performance. It is also allowable to provide any non-spherical shape. When the lower surface T1and the upper surface T2have the curved shapes including the spherical shapes, the curvatures of the lower surface T1and the upper surface T2can be appropriately determined so that all of the beams, which form the image on the surface of the substrate P, are allowed to come into the surfaces, and the angles of incidence of the light beams allowed to come into the lower surface T1and the upper surface T2are reduced in accordance with the following principle.

The numerical aperture NA of the projection optical system PL on the image plane side is represented by the following expression.
NA=n·sin θ  (1)

In this expression, n represents the refractive index of the liquid LQ, and θ represents the convergence half angle. The resolution R and the depth of focus δ are represented by the following expressions respectively.
R=k1·λ/NA(2)
δ=±k2·λ/NA2(3)

In these expressions, λ represents the exposure wavelength, and k1and k2represent the process coefficients. As described above, when the numerical aperture NA is increased about n times by the liquid LQ having the high refractive index (n), it is possible to greatly improve the resolution and the depth of focus according to the expressions (2) and (3).

When it is intended to obtain the numerical aperture NA of the projection optical system PL which is not less than the refractive index of the first optical element LS1, if the lower surface T1is a flat surface which is substantially perpendicular to the optical axis AX, then a part of the exposure light beam EL, which includes the outermost beam K of the exposure light beam EL, is totally reflected by the interface between the first optical element LS1and the liquid LQ, and the part of the exposure light beam EL cannot arrive at the image plane of the projection optical system PL. For example, the following expression holds according to the Snell's law provided that n1represents the refractive index of the first optical element LS1, n2represents the refractive index of the liquid LQ, θ1represents the angle of the outermost beam K of the exposure light beam EL allowed to come into the interface (lower surface T1) between the first optical element LS1and the liquid LQ with respect to the optical axis AX, and θ2represents the angle of the beam K allowed to outgo from the interface (allowed to come into the liquid LQ) with respect to the optical axis AX.
n1sin θ1=n2sin θ2(4)

The numerical aperture of the projection optical system PL is represented by the following expression by the refractive index n2of the liquid LQ and the angle θ2of the beam K allowed to come into the liquid LQ with respect to the optical axis AX.
NA=n2sin θ2(5)

According to the expressions (4) and (5), the following expression holds.
sin θ1=NA/n1(6)

Therefore, as clarified from the expression (6) as well, if the interface (lower surface T1) between the first optical element LS1and the liquid LQ is the flat surface substantially perpendicular to the optical axis AX, and the numerical aperture NA of the projection optical system PL is larger than the refractive index n1of the first optical element LS1, then the part of the light beam, which includes the outermost beam K of the exposure light beam EL, cannot come into the liquid LQ. On the contrary, the lower surface T1of the first optical element LS1of this embodiment has the concave surface portion2. Therefore, it is possible to lower the angle of incidence of the light beam allowed to come into the interface (lower surface T1) between the first optical element LS1and the liquid LQ, especially the beam inclined with respect to the optical axis AX of the projection optical system PL. Accordingly, even when the numerical aperture NA of the projection optical system PL is larger than the refractive index n1of the first optical element LS1, the outmost beam K of the exposure light beam EL can arrive at the image plane satisfactorily without being totally reflected by the interface.

Next, an explanation will be made about the liquid supply mechanism10and the liquid recovery mechanism20of the liquid immersion mechanism1.FIG. 3shows parts of the liquid supply mechanism10. As shown inFIGS. 1 and 3, the liquid supply mechanism10of this embodiment is provided with a first liquid supply section11which is capable of feeding a first liquid LQ1, a second liquid supply section12which is capable of feeding a second liquid LQ2, and a mixing unit19which mixes the first liquid LQ1fed from the first liquid supply section11and the second liquid LQ2fed from the second liquid supply section12. The liquid LQ, which is prepared by the mixing unit19, is supplied to the image plane side of the projection optical system PL. The first liquid LQ1and the second liquid LQ2are different from each other. The mixing unit19mixes the two types of the liquids LQ1, LQ2. As described above, the exposure apparatus of this embodiment is provided with the mixing unit which mixes the two types of the liquids LQ1, LQ2. Accordingly, it is possible to appropriately adjust the optical properties such as the transmittance and the refractive index of the liquid LQ for forming the liquid immersion area LR. In this embodiment, glycerol, which has a refractive index of about 1.61, is used as the first liquid LQ1, and isopropanol, which has a refractive index of about 1.50, is used as the second liquid LQ2. The amounts of the first liquid LQ1and the second liquid LQ2are adjusted so that the liquid LQ, which is obtained by mixing them, has a refractive index of about 1.60.

Each of the first and second liquid supply sections11,12includes, for example, a tank for accommodating the first or second liquid LQ1, LQ2, a pressurizing pump, a temperature-adjusting unit for adjusting the temperature of the first or second liquid LQ1, LQ2to be supplied, a filter unit for removing any foreign matter (including any bubble) from the first or second liquid LQ1, LQ2, and the like. It is not necessary that the exposure apparatus EX is provided with all of the tank, the pressurizing pump, the filter unit and the like of the liquid supply mechanism10. These components may be replaced with the equipment of a factory or the like in which the exposure apparatus EX is installed. One end of a first supply tube13is connected to the first liquid supply section11. The other end of the first supply tube13is connected to a collective tube15. One end of a second supply tube14is connected to the second liquid supply section12. The other end of the second supply tube14is connected to the collective tube15. The first liquid LQ1, which is fed from the first liquid supply section11, is allowed to flow through the first supply tube13, and then the first liquid LQ1is supplied to the mixing unit19via the collective tube15. The second liquid LQ2, which is fed from the second liquid supply section12, is allowed to flow through the second supply tube14, and then the second liquid LQ2is supplied to the mixing unit19via the collective tube15.

Valves13B,14B are provided for the first and second supply tubes13,14respectively. The operations of the valves13B,14B are controlled by the control unit CONT. The control unit CONT adjusts the valves13B,14B (opening degrees of the valves13B,14B), and thus the supply amounts per unit time of the first and second liquids LQ1, LQ2, which are supplied from the first and second liquid supply sections11,12to the mixing unit19via the first and second supply tubes13,14and the collective tube15, are adjusted respectively.

The liquid LQ, which is returned from the liquid recovery mechanism20, can be also supplied to the mixing unit19. The liquid LQ, which is returned from the liquid recovery mechanism20, is supplied to the mixing unit19via a return tube27. The mixing unit19mixes the first and second liquids LQ1, LQ2supplied from the first and second liquid supply sections11,12via the first and second supply tubes13,14and the collective tube15with the liquid LQ supplied from the liquid recovery mechanism20via the return tube27. One end of a supply tube16is connected to the mixing unit19, and the other end is connected to the nozzle member70. A supply internal flow passage, which has one end connected to the supply port18, is formed in the nozzle member70. The other end of the supply tube16is connected to the other end of the supply internal flow passage. The liquid LQ, which is prepared or produced by the mixing unit19, is supplied to the nozzle member70via the supply tube16. The liquid LQ is allowed to flow through the supply internal flow passage of the nozzle member70, and then the liquid LQ is supplied from the supply port18to the image plane side of the projection optical system PL.

With reference toFIG. 1, the liquid recovery mechanism20includes a liquid recovery section21which is capable of recovering the liquid LQ in order to recover the liquid LQ on the image plane side of the projection optical system PL, and a recovery tube26which has one end connected to the liquid recovery section21. The other end of the recovery tube26is connected to the nozzle member70. The liquid recovery section21is provided with, for example, a vacuum system (suction unit) such as a vacuum pump or the like, a gas/liquid separator for separating the recovered liquid LQ from the gas, and a tank for accommodating the recovered liquid LQ. It is not necessary that the exposure apparatus EX is provided with all of the vacuum system, the gas/liquid separator, the tank and the like of the liquid recovery mechanism20. These components may be replaced with the equipment of a factory or the like in which the exposure apparatus EX is installed. A recovery internal flow passage, which has one end connected to the recovery port28, is formed in the nozzle member70. The other end of the recovery tube26is connected to the other end of the recovery internal flow passage of the nozzle member70. When the vacuum system of the liquid recovery section21is driven, then the liquid LQ on the substrate P, which is arranged on the image plane side of the projection optical system PL, is allowed to flow into the recovery internal flow passage from the recovery port28, and the liquid LQ is recovered by the liquid recovery section21via the recovery tube26.

The liquid recovery mechanism20is provided with a process unit60which applies a predetermined treatment to the recovered liquid LQ. The liquid recovery mechanism20returns the liquid LQ after being processed with the process unit60to the mixing unit19of the liquid supply mechanism10via the return tube27. The process unit60cleans the recovered liquid LQ, which includes, for example, a filter unit and a distillation unit. The liquid LQ, which is recovered by the liquid recovery mechanism20, may possibly contain any impurity generated from the substrate P due to the contact with the substrate P coated with the resist. Accordingly, the liquid recovery mechanism20cleans a part of the recovered liquid LQ with the process unit60, and then the cleaned liquid LQ is returned to the mixing unit19of the liquid supply mechanism10. A part of the residual of the recovered liquid LQ is discharged (discarded) by the liquid recovery mechanism20to the outside of the exposure apparatus EX without returning the part of the residual of the recovered liquid LQ to the liquid supply mechanism10.

The liquid supply mechanism10further includes a measuring unit30which measures the optical property of the liquid LQ to be supplied to the image plane side of the projection optical system PL. The measuring unit30includes a first measuring unit31which is provided at an intermediate position of the return tube27disposed between the mixing unit19and the process unit60of the liquid recovery mechanism20, and a second measuring unit32which is provided at an intermediate position of the supply tube16disposed between the mixing unit19and the nozzle member70. The first measuring unit31measures the optical property of the liquid LQ which is returned from the process unit60of the liquid recovery mechanism20before being supplied to the mixing unit19. The second measuring unit32measures the optical property of the liquid LQ which is prepared by the mixing unit19before being supplied to the image plane side of the projection optical system PL via the nozzle member70. The first measuring unit31and the second measuring unit32are constructed substantially equivalently, which can measure at least one of the refractive index of the liquid LQ and the transmittance of the liquid LQ.

The control unit CONT adjusts the first and second valves13B,14B provided for the first and second supply tubes13,14on the basis of the measurement result of the first measuring unit31to adjust the supply amounts per unit time of the first and second liquids LQ1, LQ2to be supplied from the first and second liquid supply sections11,12to the mixing unit19respectively. In other words, the control unit CONT adjusts the mixing ratio of the first and second liquids LQ1, LQ2supplied from the first and second liquid supply sections11,12respectively and mixed in the mixing unit19on the basis of the measurement result of the first measuring unit31. In this embodiment, the mixing ratio of the first liquid LQ1and the second liquid LQ2is adjusted so that the refractive index is approximately 1.60.

The first and second liquids LQ1, LQ2are the liquids of the different types. Therefore, the optical properties (refractive index, light transmittance) may be highly possibly different from each other. Accordingly, in order to obtain the desired state of the optical property of the liquid LQ to be prepared by the mixing unit19, specifically in order to maintain a predetermined value of at least one of the refractive index and the light transmittance of the liquid LQ prepared by the mixing unit19, the control unit CONT adjusts the mixing ratio of the first and second liquids LQ1, LQ2subjected to the mixing in the mixing unit19on the basis of the measurement result of the first measuring unit31. The first measuring unit31measures the optical property of the liquid LQ returned from the liquid recovery mechanism20. Therefore, the control unit CONT can maintain the desired state of the optical property of the liquid LQ prepared by the mixing unit19such that appropriate amounts of the first and second liquids LQ1, LQ2are appropriately added to the returned liquid LQ from the first and second liquid supply sections11,12on the basis of the measurement result of the first measuring unit31. As described above, each of the first and second liquid supply sections11,12is provided with the temperature-adjusting unit for maintaining the constant temperature of each of the first and second liquids LQ1, LQ2. Therefore, the control unit CONT avoids the fluctuation of the optical property of the liquid LQ which would be otherwise caused by the fluctuation of the temperature of the liquid LQ, by controlling the temperature-adjusting unit.

The relationship between the mixing ratio of the first and second liquids LQ1, LQ2and the optical property of the liquid LQ prepared on the basis of the mixing ratio is previously determined, for example, by an experiment or simulation. The information about the relationship is previously stored in the storage unit MRY connected to the control unit CONT. The control unit CONT can adjust the first and second valves13B,14B on the basis of the information stored in the storage unit MRY and the measurement result obtained by the first measuring unit31to determine the mixing ratio of the first and second liquids LQ1, LQ2in order to obtain the desired optical property of the liquid LQ.

The optical property of the liquid LQ prepared by the mixing unit19is measured by the second measuring unit32. The control unit CONT adjusts, for example, the positional relationship between the surface of the substrate P and the position of the image plane formed via the projection optical system PL and the liquid LQ on the basis of the measurement result of the second measuring unit32. Specifically, the control unit CONT uses the image formation characteristic-adjusting unit LC provided for the projection optical system PL on the basis of the measurement result of the second measuring unit32so that the specified optical element of the plurality of optical elements LS1to LS5for constructing the projection optical system PL is driven and/or the pressure in the barrel PK is adjusted to adjust the position of the image plane of the projection optical system PL thereby. Accordingly, even when, for example, the refractive index, which is included in the optical property of the liquid LQ prepared by the mixing unit19, is slightly varied, and the image plane position via the projection optical system PL and the liquid LQ is varied, then the image formation characteristic is adjusted in response to the optical property (refractive index) of the liquid LQ, and thus the surface of the substrate P can be aligned with the position of the image plane formed via the projection optical system PL and the liquid LQ. The control unit CONT may be operated such that the surface position of the substrate P is adjusted by driving the substrate stage PST, the mask stage MST, which holds the mask M, is driven, and/or the temperature of the liquid LQ to be supplied is adjusted, in place of the adjustment of the projection optical system PL by the image formation characteristic-adjusting unit LC or in combination with the adjustment by the image formation characteristic-adjusting unit LC. In this case, the relationship between the optical property of the liquid LQ and the position of the image plane formed via the projection optical system PL and the liquid LQ is previously determined, for example, by an experiment or simulation, and the information about the relationship is previously stored in the storage unit MRY connected to the control unit CONT. The control unit CONT can use, for example, the image formation characteristic-adjusting unit LC on the basis of the information stored in the storage unit MRY and the measurement result of the second measuring unit32so that the surface of the substrate P is consistent or coincident with the position of the image plane formed via the projection optical system PL and the liquid LQ. When the light transmittance, which is included in the optical property of the liquid LQ, is varied, the control unit CONT adjusts, for example, the illumination optical system IL including the light source on the basis of the measurement result of the second measuring unit32, and the exposure amount control parameter can be adjusted in the scanning exposure including, for example, the scanning velocity of the substrate P and the radiation amount (illuminance) of the exposure light beam EL.

Next, the removing unit40will be explained.FIG. 4shows the removing unit40. As shown inFIGS. 1 and 4, the exposure apparatus EX is provided with the removing unit40which removes the foreign matter in the space inside of the concave surface portion2of the first optical element LS1. The removing unit40includes the suction member42which has the suction port43for sucking the foreign matter and which is provided for the substrate stage PST. As shown inFIG. 4, the removing unit40includes the suction member42which is arranged inside a hole45formed at a part of the upper surface87of the substrate stage PST, and a driving mechanism44which drives the suction member42. The suction member42is a pipe-shaped member, and its upper end (one end) is the suction port43. The suction port43is provided on the upper surface87of the substrate stage PST. The suction port43is arranged outside the exposure light beam EL during the exposure for the substrate P. The suction member42is movable in the Z axis direction in accordance with the driving force of the driving mechanism44. The suction port43appears and disappears with respect to the upper surface87of the substrate stage PST. In this embodiment, when the suction member42is moved downwardly and arranged inside the hole45, the suction port43, which is provided at the upper end of the suction member42, is substantially flush with the upper surface87of the substrate stage PST as shown inFIG. 4. The suction member42may be movable in the oblique direction in relation to the Z axis direction.

The suction port43, which is provided on the upper surface87of the substrate stage PST, can be opposed to the concave surface portion2on the lower surface T1of the first optical element LS1of the projection optical system PL in accordance with the movement of the substrate stage PST. On the other hand, the lower end (the other end) of the suction member42is connected to the suction unit41via a flow passage-forming member46. The suction unit41includes, for example, a vacuum system such as a vacuum pump, which is capable of sucking and recovering the liquid. A part of the flow passage-forming member46has an expandable/contractible portion47which is expandable/contractible in order not to inhibit the movement of the suction member42.

Next, an explanation will be made with reference to a flow chart shown inFIG. 12about the operation for exposing the substrate P by the exposure apparatus EX constructed as described above. When the substrate P is subjected to the exposure, the control unit CONT starts the operation for forming the liquid immersion area LR of the liquid LQ by the liquid immersion mechanism1. It is assumed that the substrate P to be subjected to the exposure process is already loaded on the substrate holder PH. When the operation for forming the liquid immersion area LR is started, the control unit CONT moves the substrate stage PST so that the concave surface portion2of the first optical element LS1of the projection optical system PL is opposed to the recovery port43of the removing unit40. The control unit CONT starts the supply operation of the liquid LQ by the liquid supply mechanism10of the liquid immersion mechanism1and the recovery operation of the liquid LQ by the liquid recovery mechanism20in the state in which the concave surface portion2of the first optical element LS1of the projection optical system PL is opposed to the recovery port43of the removing unit40(S1).

FIG. 5shows a state which is brought about immediately after starting the operation for forming the liquid immersion area LR. As shown inFIG. 5, when the operation for forming the liquid immersion area LR is started, there is such a possibility that any bubble (gas portion) may be formed in the liquid LQ. There is such a possibility that the bubble may be also formed after the elapse of a predetermined period of time after the start of the operation for forming the liquid immersion area LR depending on the state of the liquid immersion mechanism1. In this embodiment, the first optical element LS1has the concave surface portion2. Therefore, there is such a high possibility that the bubble, which has a specific gravity smaller than that of the liquid LQ, stays at the highest position of the concave surface portion2or in the vicinity thereof. The control unit CONT drives the driving mechanism44of the removing unit40to move the suction member42upwardly so that the suction port43, which is provided at the upper end of the suction member42, is moved in the +Z direction, and the substrate stage PST, on which the suction member42is provided, is moved in the XY directions by the aid of the substrate stage-driving unit PSTD. Accordingly, the control unit CONT moves the suction port43relatively with respect to the concave surface portion2by the driving mechanism44and the substrate stage-driving unit PSTD to arrange the suction port43at the position optimum for the concave surface portion2. Specifically, the control unit CONT arranges the suction port43of the removing unit44at the position in the vicinity of the position at which the bubble is arranged, i.e., at the highest position of the concave surface portion2or in the vicinity thereof, by the driving mechanism44and the substrate stage-driving unit PSTD. The control unit CONT drives the suction unit41in a state in which the suction port43is allowed to approach the concave surface portion2while leaving a predetermined distance (for example, about 1 mm) to suck and remove the bubble having the specific gravity smaller than that of the liquid LQ by the aid of the suction port43, the bubble being contained in the liquid LQ in the space inside of the concave surface portion2(S2). In this procedure, the liquid supply operation by the liquid supply mechanism10of the liquid immersion mechanism1and the liquid recovery operation by the liquid recovery mechanism20are continued even when the operation to remove the bubble is performed by the removing unit40. The suction amount and the relative distance between the suction port43and the concave surface portion2, which are provided when the suction-port43sucks the bubble, are optimally adjusted depending on the physical properties such as the viscosity of the liquid LQ to be used. The suction operation (removal operation) may be executed while moving the suction port43in the Z direction (+Z direction and/or −Z direction). Alternatively, the suction operation (removal operation) may be executed while moving the suction port43in the direction perpendicular to the Z axis so that the suction port43does not collide with the concave surface portion2.

The removing unit40can suck and remove any foreign matter having a specific gravity smaller than that of the liquid LQ in the liquid LQ in the space inside of the concave surface portion2without being limited to the bubble contained in the liquid LQ.

In this procedure, the operation for forming the liquid immersion area LR is started by the liquid immersion mechanism1in the state in which the suction port43is opposed to the concave surface portion2. However, the following procedure is also available. That is, the liquid immersion area LR is formed in an area (including the surface of the substrate P) of the upper surface87of the substrate stage PST, the area being away from an area in which the suction port43is provided. After that, the substrate stage PST is moved in the XY directions so that the suction port43is opposed to the concave surface portion2of the first optical element LS1. The foreign matter in the space inside of the concave surface portion2can be also removed smoothly such that the concave surface portion2is opposed to the suction port43, and then the suction port43is allowed to approach the concave surface portion2to start the suction operation.

After the operation for removing the bubble contained in the liquid LQ is completed, the control unit CONT moves the suction member42of the removing unit40downwardly so that the suction member42is arranged inside the hole45. The control unit CONT confirms, by the detection unit50, whether or not the bubble (foreign matter) is removed from the liquid LQ in the space inside of the concave surface portion2. That is, the control unit CONT moves the substrate stage PST in the XY directions so that the liquid immersion area LR, which is formed on the upper surface87of the substrate stage PST, is moved to the position over or above the detection unit50. In this procedure, the liquid supply operation by the liquid supply mechanism10of the liquid immersion mechanism1and the liquid recovery operation by the liquid recovery mechanism20are also continued during the period in which the substrate stage PST is moved in the XY directions.

FIG. 6shows a state in which the detection unit50detects the foreign matter (including the bubble). With reference toFIG. 6, the detection unit50is provided at the inside of the substrate stage PST. The detection unit50is arranged in the internal space56of the substrate stage PST. The detection unit50includes an optical system51which is arranged under a transparent member54, and an image pickup element53which is composed of, for example, CCD. The image pickup element53is capable of obtaining an optical image (image) of, for example, the liquid LQ and the first optical element LS1via the transparent member54and the optical system51. The image pickup element53coverts the obtained image into an electric signal, and the signal (image information) is outputted to the control unit CONT. The detection unit50further includes an adjusting mechanism52which is capable of adjusting the focus position of the optical system51. The detection unit50has a field capable of observing the entire liquid LQ arranged inside the concave surface portion2. The entire detection unit50may be arranged in the substrate stage PST. Alternatively, for example, a part of the optical element among a plurality of optical elements for constructing the optical system51and the image pickup element53, and the like may be arranged outside the substrate stage PST. Another arrangement may be also adopted, in which the adjusting mechanism52is omitted.

The control unit CONT uses the detection unit50to detect whether or not any bubble (foreign matter) is present in the liquid LQ of the liquid immersion area LR formed on the transparent member54(S3). The detection unit50observes, through the transparent member54, the liquid LQ of the liquid immersion area LR on the upper surface of the transparent member54. When the detection unit50observes the state of the liquid immersion area LR, the substrate stage PST substantially stands still. The image pickup element53of the detection unit50obtains the image of the liquid LQ for forming the liquid immersion area LR on the transparent member54, via the transparent member54and the optical system51. When the bubble (foreign matter) in the space inside of the concave surface portion2, is detected by the detection unit50, the control unit CONT uses the adjusting mechanism52to adjust the focus position of the optical system51to the position in the vicinity of the concave surface portion2. Therefore, the image pickup element53can satisfactorily obtain the image of the liquid LQ in the concave surface portion2disposed over or above the transparent member54. The detection unit50has the field which is larger than the concave surface portion2. Therefore, it is possible to collectively obtain the full field image of the liquid LQ in the space inside of the concave surface portion2.

The image information obtained by the image pickup element53is outputted to the control unit CONT. The control unit CONT performs the calculation processing (image processing) for the signal (image information) outputted from the image pickup element53to judge whether or not the bubble (foreign matter) is present in the liquid LQ on the basis of the result of the processing (S4).

If it is judged or determined that the bubble (foreign matter) is absent in the liquid LQ on the basis of the detection result of the detection unit50, the control unit CONT performs the measurement process by various measuring units (not shown) provided on the substrate stage PST (S5). That is, the control unit CONT moves the substrate stage PST in the XY directions to move the liquid immersion area LR onto the measuring unit from the position on the transparent member54. The measuring unit as described above is provided to perform the measurement process in relation to the exposure process. The measuring unit includes a substrate alignment system based on the FIA (field image alignment) system as disclosed, for example, in Japanese Patent Application Laid-open No. 4-65603 and a reference member having any mark to be measured by a mask alignment system based on the VRA (visual reticle alignment) as disclosed, for example, in Japanese Patent Application Laid-open No. 7-176468. The measuring unit further includes, for example, unevenness sensors for measuring the uneven illuminance as disclosed in Japanese Patent Application Laid-open No. 57-117238 and for measuring the fluctuation amount of the transmittance of the exposure light beam EL of the projection optical system PL as disclosed in Japanese Patent Application Laid-open No. 2001-267239, a spatial image-measuring sensor as disclosed in Japanese Patent Application Laid-open No. 2002-14005, and a radiation amount sensor (illuminance sensor) as disclosed in Japanese Patent Application Laid-open No. 11-16816. The measurement process is performed in a state in which the liquid immersion area LR of the liquid LQ is arranged on a predetermined measuring unit of the respective measuring units as described above. The baseline amount is derived and the calibration process for the projection optical system PL is performed by the control unit CONT on the basis of the measurement result obtained thereby. The reference member and the sensor, which are to be used for the measurement process as described above, will be briefly explained in a third embodiment described later on.

After the completion of, for example, the calibration process for the projection optical system PL, the control unit CONT moves the substrate stage PST in the XY directions so that the liquid immersion area LR, which is formed on the upper surface87of the substrate stage PST, is moved onto the substrate P. The control unit CONT radiates the exposure light beam EL onto the substrate P via the projection optical system PL and the liquid LQ from which the bubble (foreign matter) is removed to expose the substrate P (S6).

On the other hand, if it is judged that the bubble (foreign matter) is present in the liquid LQ (YES in S4) on the basis of the detection result of the detection unit50, then the control unit CONT moves the substrate stage PST in the XY directions, and the liquid immersion area LR is moved again from the position on the transparent member54to the position over or above the recovery port43of the removing unit40. The control unit CONT performs the operation for removing the bubble (foreign matter) by the removing unit40(S1). After performing the operation for removing the bubble (foreign matter) by the removing unit40, the control unit CONT uses the detection unit50again to detect whether or not the bubble (foreign matter) is present in the liquid LQ (S2). The operation as described above is repeated until the bubble (foreign matter) is not detected in the liquid LQ by the detection unit50. After the bubble (foreign matter) is not detected in the liquid LQ, the liquid immersion exposure is performed for the substrate P (S6).

In this procedure, after the liquid immersion area LR is formed by the liquid immersion mechanism1, the control unit CONT uses the removing unit40to perform the operation for removing the bubble (foreign matter) contained in the liquid LQ, and then the control unit CONT uses the detection unit50to detect whether or not the bubble (foreign matter) contained in the liquid LQ is removed. However, it is also allowable to detect whether or not the bubble (foreign matter) is present in the liquid LQ by the detection unit50without performing the operation for removing the bubble (foreign matter) contained in the liquid LQ by the removing unit40after forming the liquid immersion area LR by the liquid immersion mechanism1. In this procedure, when it is judged that the bubble (foreign matter) is absent in the liquid LQ on the basis of the detection result of the detection unit50, the control unit CONT can perform the measurement process based on the use of the measuring unit and the exposure process for the substrate P without performing the removing operation by the removing unit40. Therefore, it is possible to omit any useless operation which would be otherwise performed such that the removing operation is performed by the removing unit40although the bubble (foreign matter) is absent in the liquid LQ.

The control unit CONT can also perform the operation for removing the bubble (foreign matter) based on the use of the removing unit40, for example, at every predetermined period of time or every time when a predetermined number of substrates are processed, irrelevantly to the detection result of the detection unit50. The operation for removing the bubble (foreign matter) by the removing unit40and the detecting operation by the detection unit50may be performed after the exposure for the substrate P (before unloading the substrate P from the substrate holder PH).

As explained above, the first optical element LS1, which is included in the plurality of optical elements LS1to LS5for constructing the projection optical system PL and which is disposed closest to the image plane of the projection optical system PL, has the concave surface portion2which makes contact with the liquid LQ. Therefore, even when the liquid LQ has the refractive index higher than that of the first optical element LS1, the exposure light beam EL is successfully allowed to arrive at the substrate P (image plane) arranged on the image plane side of the projection optical system PL satisfactorily via the first optical element LS1and the liquid LQ. Even when any bubble (foreign matter) enters the space inside of the concave surface portion2, the bubble (foreign matter) is removed by the removing unit40. Therefore, it is possible to allow the exposure light beam EL to satisfactorily arrive at the substrate P (image plane) arranged on the image plane side of the projection optical system PL.

Second Embodiment

Next, a second embodiment will be explained with reference toFIG. 7. In the following description, any explanation will be simplified or omitted for constitutive parts which are the same as or equivalent to those of the embodiment described above. The point of the second embodiment different from the first embodiment, i.e., the feature of the second embodiment resides in the fact that a part of the removing unit40is provided for a nozzle member70′. That is, in the second embodiment, a suction port43′ of the removing unit40is provided on the nozzle member70′. The suction port43′ is connected to the suction unit41via a flow passage46′ formed in the nozzle member70′. As shown inFIG. 7, a part of the nozzle member70′ is arranged under the concave surface portion2of the first optical element LS1. An opposing surface71, which is opposed to the concave surface portion2, is formed by the part of the nozzle member70′ arranged under the concave surface portion2. The suction port43′ is formed on the opposing surface71.

In the projection optical system PL of this embodiment, the optical path for the exposure light beam EL is deviated with respect to the optical axis AX (Z axis). That is, an area (hereinafter referred to as “effective area”) A1of the concave surface portion2, through which the exposure light beam EL passes, is deviated with respect to the center of the concave surface portion2(highest position of the concave surface portion2). An area (hereinafter referred to as “non-effective area”) A2, through which the exposure light beam EL does not pass, is provided in the vicinity of the highest position of the concave surface portion2. The opposing surface71is provided opposite to the non-effective area A2of the concave surface portion2. The suction port43′, which is provided on the opposing surface71, is provided at the position opposed to the concave surface portion2outside the optical path for the exposure light beam EL.

The bubble (foreign matter) in the space inside of the concave surface portion2, can be also removed by the aid of the suction port43′ without disturbing the passage of the exposure light beam EL by providing the suction port43′ at the part of the nozzle member70′ at the position outside the optical path for the exposure light beam EL opposite to the concave surface portion2. In this embodiment, it is also possible to concurrently perform the exposure operation for the substrate P in a state in which the optical path space for the exposure light beam EL between the first optical element LS1and the substrate P is filled with the liquid LQ and the sucking operation by the removing unit40by the aid of the suction port43′.

Third Embodiment

Next, a third embodiment will be explained with reference toFIGS. 8 to 10. The point of the third embodiment different from the first embodiment, i.e., the feature of the third embodiment resides in the fact that an exposure apparatus EX2has first and second stages PST1, PST2which are movable on the image plane side of the projection optical system PL. The first stage PST1is a substrate stage which is movable while holding the substrate P. The second stage PST2is a measuring stage which carries measuring units for performing the measurement process in relation to the exposure process as disclosed, for example, in Japanese Patent Application Laid-open No. 11-135400. The removing unit40and the detection unit50are provided for the measuring stage PST2.

As shown in a plan view inFIG. 9, a reference member300, which has marks as described above, is provided as the measuring unit on an upper surface88of the measuring stage PST2. An upper plate400for constructing an unevenness sensor as described above, an upper plate500for constructing a part of a spatial image-measuring sensor, and an upper plate600for constructing a part of a radiation amount sensor (illuminance sensor) are provided as measuring units on the upper surface88. The upper surface of the reference member300and the upper surfaces of the upper plates400,500,600are substantially flush with the upper surface88of the measuring stage PST2and the upper surface of the transparent member54of the detection unit50. The measuring units provided for the measuring stage PST2are not limited to those described herein. It is possible to carry various measuring units, if necessary.

When the substrate P is exposed by the exposure apparatus EX2, the control unit CONT firstly drives the liquid immersion mechanism1to form the liquid immersion area LR on the measuring stage PST2in a state in which the first optical element LS1of the projection optical system PL is opposed to the measuring stage PST2. Subsequently, the control unit CONT performs the operation for removing the bubble (foreign matter) contained in the space inside of the concave surface portion2of the first optical element LS1by the removing unit40provided for the measuring stage PST2in the same manner as in the first embodiment. The control unit CONT confirms whether or not the bubble (foreign matter) contained in the space inside of the concave surface portion2is removed, by the detection unit50. If it is judged that the bubble (foreign matter) is present in the space inside of the concave surface portion2on the basis of the detection result obtained by the detection unit50, the control unit CONT performs the operation for removing the bubble (foreign matter) by the removing unit40again. On the other hand, if it is judged that the bubble (foreign matter) is absent in the space inside of the concave surface portion2on the basis of the detection result obtained by the detection unit50, the control unit CONT moves the liquid immersion area LR onto the substrate stage PST1after performing the measurement process by the various measuring units as described above. In this procedure, the control unit CONT moves the substrate stage PST1to the load position to load the substrate P to be subjected to the exposure process on the substrate stage PST1during the period in which the operation for removing the bubble (foreign matter) based on the use of the removing unit40provided on the measuring stage PST2, the operation for detecting the bubble (foreign matter) based on the use of the detection unit50, or the measurement process based on the use of the measuring unit is performed.

As shown inFIG. 10, when the liquid immersion area LR on the measuring stage PST2is moved onto the substrate stage PST1, then the control unit CONT moves the substrate stage PST1and the measuring stage PST2in the XY directions together in a state in which the substrate stage PST1and the measuring stage PST2are allowed to make approach closely to one another or make contact with each other, and the liquid immersion area LR is moved between the upper surface87of the substrate stage PST1and the upper surface88of the measuring stage PST2. After the liquid immersion area LR is moved onto the substrate stage PST1, the control unit CONT exposes the substrate P on the substrate stage PST1via the projection optical system PL and the liquid LQ. The control unit CONT performs the exposure process for the substrate P in consideration of the measurement result of the measurement process performed on the measuring stage PST2.

In the first to third embodiments described above, the control unit CONT may start the suction operation while the suction port43of the removing unit40is moved closer to the concave surface portion2by a predetermined distance before the operation for forming the liquid immersion area LR is started, i.e., in a state in which the side of the lower surface T1of the concave surface portion2is not filled with the liquid LQ. The supply operation and the recovery operation for the liquid LQ by the liquid immersion mechanism1may be started in a state in which the suction operation is continued by the aid of the suction port43. Accordingly, it is possible to further suppress the formation of the bubble (gas portion). When the suction operation is started by the aid of the suction port43before being filled with the liquid LQ, then the foreign matter, which floats in the gas space inside of the concave surface portion2, can be removed, and then the side of the lower surface T1of the concave surface portion2can be filled with the liquid LQ.

In the embodiments described above, the explanation has been made as exemplified by the case in which the suction port of the removing unit is provided, for example, on the nozzle member, the movable member, and the like (for example, the substrate stage, the measuring stage, and the like) which is movable on the image plane side of the projection optical system PL by way of example. However, for example, a suction member having a suction port may be supported by a support member called “column (body)” for supporting the projection optical system PL. Alternatively, a suction port to be connected to the suction unit may be formed at a portion of the concave surface portion2of the first optical element LS1outside the optical path for the exposure light beam EL.

In the embodiments described above, the removing unit40removes the bubble (foreign matter) in the concave surface portion2formed on the lower surface T1of the first optical element LS1which is disposed closest to the image plane of the projection optical system PL and which is included in the plurality of optical elements LS1to LS5for constructing the projection optical system PL. However, a concave surface portion, which makes contact with the liquid, may be formed on any surface other than the lower surface of the first optical element LS1depending on the arrangement of the projection optical system PL. Alternatively, a concave surface portion, which makes contact with the liquid, may be formed on any one of the optical elements LS2to LS5other than the first optical element LS1. For example, the liquid may be introduced into the space between the first optical element and the second optical element, and a lens, which has a concave curved surface as the lower surface (surface opposed to the first optical element), may be used as the second optical element. Even in the case of such an arrangement, it is possible to maintain the characteristic of the projection optical system PL by providing the removing unit to remove any foreign matter in the space inside of the concave surface portion.

In the embodiments described above, the liquid supply mechanism10is constructed such that the two types of the first and second liquids LQ1, LQ2are mixed in the mixing unit19, and the liquid LQ, which is prepared by the mixing unit19, is supplied to the image plane side of the projection optical system PL. However, it is of course possible to provide such an arrangement that a plurality of arbitrary liquids of three or more types are mixed in the mixing unit19, and the liquid LQ prepared by the mixing unit19is supplied.

Alternatively, the liquid supply mechanism10may supply one type of liquid (liquid having a refractive index higher than the refractive index of the first optical element LS1) without mixing the plurality of types of liquids. In this case, the liquid supply mechanism10is constructed to have no mixing unit19.

The liquid LQ, which is supplied by the liquid supply mechanism10, includes, for example, predetermined liquids having C—H bond and O—H bond such as isopropanol and glycerol, and predetermined liquid (organic solvents) such as hexane, heptane, decane, and the like. Alternatively, it is also allowable to use those obtained by mixing two or more arbitrary liquids of the predetermined liquids. Further alternatively, it is also allowable to use those obtained by adding (mixing) the predetermined liquid to pure water. Further alternatively, the liquid LQ, which is supplied by the liquid supply mechanism10, may include those obtained by adding (mixing) a base or an acid for liberating anion or cation such as H+, Cs+, K+, Cl−, SO42−, PO42−, and the like to pure water. Further alternatively, it is also allowable to use those obtained by adding (mixing) fine particles of Al oxide or the like to pure water. The ArF excimer laser beam is transmissive through the liquid LQ as described above. As for the liquid LQ, it is preferable to use those in which the light absorption coefficient is small, the properties such as the refractive index scarcely depend on the temperature, and the liquid LQ is stable against the resist coated on the surface of the substrate P and the projection optical system PL.

Those having refractive indexes of about 1.6 to 1.8 may be used as the liquid LQ. Further, as for the first optical element LS1, any material having a refractive index (for example, not less than 1.6) higher than those of silica glass and calcium fluoride may be used to form the first optical element LS1.

In the embodiments described above, the liquid immersion area LR is formed with the liquid having the refractive index higher than the refractive index of the first optical element LS1. However, there is no limitation thereto. For example, a liquid having a refractive index lower than the refractive index of the first optical element LS1may be used. For example, a lens made of silica glass may be used as the first optical element LS1, and pure water may be used as the liquid LQ. In the case of such an arrangement, the total reflection tends to occur when the angle of inclination of the light component of the light flux, especially the outermost beam of the light flux, with respect to the optical axis (or NA) is increased, the light flux being allowed to come from the first optical element LS1into the interface between the first optical element LS1and the liquid LQ, and the light component being inclined with respect to the optical axis AX. Therefore, the arrangement, in which the surface of the optical element included in the projection optical system to make contact with the liquid is the concave surface, especially the concave curved surface, is effective regardless of the refractive index of the liquid LQ with respect to the refractive index of the optical element, because it is possible to lower the angle of incidence into the interface between the liquid and the optical element.

In the first to third embodiments described above, the ArF excimer laser is used as the exposure light beam EL. However, as described above, it is possible to adopt various types of exposure light beams (exposure beams) including, for example, the F2laser. As for the liquid LQ to be supplied from the liquid supply mechanism10, any optimum liquid can be appropriately used depending on, for example, the exposure light beam (exposure beam) EL, the numerical aperture of the projection optical system PL, and the refractive index of the first optical element LS1with respect to the exposure light beam EL.

In the first to third embodiments described above, at least a part of the liquid LQ recovered by the liquid recovery mechanism20is returned to the liquid supply mechanism10. However, all of the liquid, which is recovered by the liquid recovery mechanism20, may be discarded, and the new and clean liquid LQ may be supplied from the liquid supply mechanism10. The structure of the liquid immersion mechanism1including, for example, the nozzle member70is not limited to the above. It is also possible to use those described, for example, in European Patent Publication No. 1420298 and International Publication Nos. 2004/055803, 2004/057589, 2004/057590, and 2005/029559.

In the first to third embodiments described above, the detection unit50is provided. However, the detection unit50may be omitted, and it is also allowable to judge that the bubble (foreign matter) is absent in the space inside of the concave surface portion2on the basis of the completion of the removing operation performed by the removing unit40.

In the third embodiment described above, the removing unit40may be arranged for the substrate stage PST1.

In the first to third embodiments described above, the explanation has been made about the case in which the refractive index of the first optical element LS1with respect to the exposure light beam EL is smaller than the numerical aperture NA of the projection optical system PL. However, the optical element such as the first optical element LS1, which has the concave surface portion2, can be also adopted when the refractive index of the optical element with respect to the exposure light beam is larger than the numerical aperture NA of the projection optical system PL. Also in this case, it is possible to adapt the removing unit as explained in the first to third embodiments.

When the numerical aperture NA of the projection optical system is large due to the use of the liquid immersion method as described above, it is desirable to use the polarized illumination, because the image formation performance is deteriorated due to the polarization effect in some cases with the random polarized light which has been hitherto used as the exposure light beam. In this case, it is appropriate that the linear polarized illumination, which is adjusted to the longitudinal direction of the line pattern of the line-and-space pattern of the mask (reticle), is effected so that the diffracted light of the S-polarized light component (TE-polarized light component), i.e., the component in the polarization direction along with the longitudinal direction of the line pattern is dominantly allowed to outgo from the pattern of the mask (reticle). When the space between the projection optical system PL and the resist applied to the surface of the substrate P is filled with the liquid, the diffracted light of the S-polarized light component (TE-polarized light component), which contributes to the improvement in the contrast, has the high transmittance on the resist surface, as compared with the case in which the space between the projection optical system PL and the resist applied to the surface of the substrate P is filled with the air (gas). Therefore, it is possible to obtain the high image formation performance even when the numerical aperture NA of the projection optical system exceeds 1.0. Further, it is more effective to appropriately combine, for example, the phase shift mask and the oblique incidence illumination method or the like (especially the dipole illumination method) adjusted to the longitudinal direction of the line pattern as disclosed in Japanese Patent Application Laid-open No. 6-188169. In particular, the combination of the linear polarized illumination method and the dipole illumination method is effective when the periodic direction of the line-and-space pattern is restricted to one predetermined direction and when the hole pattern is clustered in one predetermined direction. For example, when a phase shift mask of the half tone type having a transmittance of 6% (pattern having a half pitch of about 45 nm) is illuminated by the linear polarized illumination method and the dipole illumination method in combination, the depth of focus (DOF) can be increased by about 150 nm as compared with the use of the random polarized light provided that the illumination a, which is prescribed by the circumscribed circle of the two light fluxes for forming the dipole on the pupil plane of the illumination system, is 0.95, the radius of each of the light fluxes at the pupil plane is 0.125 σ, and the numerical aperture of the projection optical system PL is NA=1.2.

It is also effective to adopt a combination of the linear polarized illumination and the small σ illumination method (illumination method wherein the σvalue, which indicates the ratio between the numerical aperture NAi of the illumination system and the numerical aperture NAp of the projection optical system, is not more than 0.4).

For example, when the ArF excimer laser is used as the exposure light beam, and the substrate P is exposed with a fine line-and-space pattern (for example, line-and-space of about 25 to 50 nm) by the projection optical system PL having a reduction magnification of about ¼, then the mask M acts as a polarizing plate due to the Wave guide effect depending on the structure of the mask M (for example, the pattern fineness and the thickness of chromium), and the diffracted light of the S-polarized light component (TE-polarized light component) outgoes from the mask M in an amount larger than that of the diffracted light of the P-polarized light component (TM-polarized light component) which lowers the contrast. In this case, it is desirable to use the linear polarized illumination as described above. However, even when the mask M is illuminated with the random polarized light, it is possible to obtain the high resolution performance even when the numerical aperture NA of the projection optical system PL is large.

When the substrate P is exposed with an extremely fine line-and-space pattern on the mask M, there is such a possibility that the P-polarized light component (TM-polarized light component) is larger than the S-polarized light component (TE-polarized light component) due to the Wire Grid effect. However, for example, when the ArF excimer laser is used as the exposure light beam, and the substrate P is exposed with a line-and-space pattern larger than 25 nm by the projection optical system PL having a reduction magnification of about ¼, then the diffracted light of the S-polarized light component (TE-polarized light component) outgoes from the mask M in an amount larger than that of the diffracted light of the P-polarized light component (TM-polarized light component). Therefore, it is possible to obtain the high resolution performance even when the numerical aperture NA of the projection optical system PL is large.

Further, it is also effective to use the combination of the oblique incidence illumination method and the polarized illumination method in which the linear polarization is effected in the tangential (circumferential) direction of the circle having the center of the optical axis as disclosed in Japanese Patent Application Laid-open No. 6-53120, without being limited to only the linear polarized illumination (S-polarized illumination) adjusted to the longitudinal direction of the line pattern of the mask (reticle). In particular, when the pattern of the mask (reticle) includes not only the line pattern extending in one predetermined direction, but the pattern also includes the line patterns extending in a plurality of different directions in a mixed manner (line-and-space patterns having different periodic directions are present in a mixed manner), then it is possible to obtain the high image formation performance even when the numerical aperture NA of the projection optical system is large, by using, in combination, the zonal illumination method and the polarized illumination method in which the light is linearly polarized in the tangential direction of the circle having the center of the optical axis, as disclosed in Japanese Patent Application Laid-open No. 6-53120 as well. For example, when a phase shift mask of the half tone type having a transmittance of 6% (pattern having a half pitch of about 63 nm) is illuminated by using, in combination, the zonal illumination method (zonal ratio: 3/4) and the polarized illumination method in which the light is linearly polarized in the tangential direction of the circle having the center of the optical axis, the depth of focus (DOF) can be increased by about 250 nm as compared with the use of the random polarized light provided that the illumination a is 0.95 and the numerical aperture of the projection optical system PL is NA=1.00. In the case of a pattern having a half pitch of about 55 nm and a numerical aperture of the projection optical system NA=1.2, the depth of focus can be increased by about 100 nm.

In addition to the various types of the illumination methods as described above, it is also effective to adapt, for example, the progressive multi-focal exposure method disclosed in Japanese Patent Application Laid-open Nos. 4-277612 and 2001-345245, and the multiwavelength exposure method to obtain an effect equivalent to that of the multi-focal exposure method by a multiwavelength (for example, two wavelengths) exposure light beam.

It is also allowable that the first optical element LS1is tightly fixed so that the first optical element LS1is not moved, without allowing the first optical element LS1to be exchangeable. In this case, an exchangeable optical member may be arranged between the substrate P (image plane) and the first optical element LS1having the curved lower surface T1.

The substrate P, which is usable in the respective embodiments described above, is not limited to the semiconductor wafer for producing the semiconductor device. Those applicable include, for example, the glass substrate for the display device, the ceramic wafer for the thin film magnetic head, the master plate (synthetic silica glass, silicon wafer) for the mask or the reticle to be used for the exposure apparatus, and the like. In the embodiment described above, the light-transmissive type mask (reticle) is used, in which the predetermined light-shielding pattern (or phase pattern or dimming or light-reducing pattern) is formed on the light-transmissive substrate. However, in place of such a reticle, as disclosed, for example, in U.S. Pat. No. 6,778,257, it is also allowable to use an electronic mask on which a transmissive pattern, a reflective pattern, or a light-emitting pattern is formed on the basis of the electronic data of the pattern to be subjected to the exposure.

As for the exposure apparatus EX, the present invention is also applicable to the scanning type exposure apparatus (scanning stepper) based on the step-and-scan system for performing the scanning exposure with the pattern of the mask M by synchronously moving the mask M and the substrate P as well as the projection exposure apparatus (stepper) based on the step-and-repeat system for performing the full field exposure with the pattern of the mask M in a state in which the mask M and the substrate P are allowed to stand still, while successively step-moving the substrate P.

As for the exposure apparatus EX, the present invention is also applicable to the exposure apparatus based on the system in which the full field exposure is performed on the substrate P by a projection optical system (for example, the dioptric type projection optical system having a reduction magnification of ⅛ and including no catoptric element) with a reduction image of a first pattern in a state in which the first pattern and the substrate P are allowed to substantially stand still. In this case, the present invention is also applicable to the full field exposure apparatus based on the stitch system in which the full field exposure is further performed thereafter on the substrate P by partially overlaying a reduction image of a second pattern with respect to the first pattern by the projection optical system in a state in which the second pattern and the substrate P are allowed to substantially stand still. As for the exposure apparatus based on the stitch system, the present invention is also applicable to the exposure apparatus based on the step-and-stitch system in which at least two patterns are partially overlaid and transferred on the substrate P, and the substrate P is successively moved.

The present invention is also applicable to the twin-stage type exposure apparatus. The structure and the exposure operation of the twin-stage type exposure apparatus are disclosed, for example, in Japanese Patent Application Laid-open Nos. 10-163099 and 10-214783 (corresponding to U.S. Pat. Nos. 6,341,007, 6,400,441, 6,549,269, and 6,590,634), Japanese Patent Application Laid-open No. 2000-505958 (PCT) (corresponding to U.S. Pat. No. 5,969,441), and U.S. Pat. No. 6,208,407. The disclosures thereof are incorporated herein by reference within a range of permission of the domestic laws and ordinances of the state designated or selected in this international application.

In the first to third embodiments described above, the exposure apparatus, in which the space between the projection optical system PL and the substrate P is locally filled with the liquid, is adopted. However, the present invention is also applicable to such an exposure apparatus that the exposure is performed for a substrate in a state in which the entire surface of the substrate for exposure is immersed in the liquid, as disclosed, for example, in Japanese Patent Application Laid-open Nos. 6-124873 and 10-303114 and U.S. Pat. No. 5,825,043. The structure and the exposure operation of such a liquid immersion exposure apparatus are described in detail in U.S. Pat. No. 5,825,043. The contents of the description in this United States patent document are incorporated herein by reference within a range of permission of the domestic laws and ordinances of the state designated or selected in this international application.

As for the type of the exposure apparatus EX, the present invention is not limited to the exposure apparatus for the semiconductor device production for exposing the substrate P with the semiconductor device pattern. The present invention is also widely applicable, for example, to the exposure apparatus for producing the liquid crystal display device or for producing the display as well as the exposure apparatus for producing, for example, the thin film magnetic head, the image pickup device (CCD), the reticle, or the mask.

When the linear motor is used for the substrate stage PST and/or the mask stage MST, it is allowable to use any one of those of the air floating type based on the use of the air bearing and those of the magnetic floating type based on the use of the Lorentz's force or the reactance force. Each of the stages PST, MST may be either of the type in which the movement is effected along the guide or of the guideless type in which no guide is provided. An example of the use of the linear motor for the stage is disclosed in U.S. Pat. Nos. 5,623,853 and 5,528,118. The contents of the descriptions in the literatures are incorporated herein by reference respectively within a range of permission of the domestic laws and ordinances of the state designated or selected in this international application.

As for the driving mechanism for each of the stages PST, MST, it is also allowable to use a plane motor in which a magnet unit provided with two-dimensionally arranged magnets and an armature unit provided with two-dimensionally arranged coils are opposed to one another, and each of the stages PST, MST is driven by means of the electromagnetic force. In this case, any one of the magnet unit and the armature unit is connected to the stage PST, MST, and the other of the magnet unit and the armature unit is provided on the side of the movable surface of the stage PST, MST.

The reaction force, which is generated in accordance with the movement of the substrate stage PST, may be mechanically released to the floor (ground) by a frame member so that the reaction force is not transmitted to the projection optical system PL, as described in Japanese Patent Application Laid-open No. 8-166475 (U.S. Pat. No. 5,528,118). The contents of the descriptions in U.S. Pat. No. 5,528,118 are incorporated herein by reference within a range of permission of the domestic laws and ordinances of the state designated or selected in this international application.

The reaction force, which is generated in accordance with the movement of the mask stage MST, may be mechanically released to the floor (ground) by a frame member so that the reaction force is not transmitted to the projection optical system PL, as described in Japanese Patent Application Laid-open No. 8-330224 (U.S. Pat. No. 5,874,820). The disclosure of U.S. Pat. No. 5,874,820 is incorporated herein by reference within a range of permission of the domestic laws and ordinances of the state designated or selected in this international application.

As described above, the exposure apparatus EX according to the embodiment of the present invention is produced by assembling the various subsystems including the respective constitutive elements as defined in claims so that the predetermined mechanical accuracy, the electric accuracy, and the optical accuracy are maintained. In order to secure the various accuracies, those performed before and after the assembling include the adjustment for achieving the optical accuracy for the various optical systems, the adjustment for achieving the mechanical accuracy for the various mechanical systems, and the adjustment for achieving the electric accuracy for the various electric systems. The steps of assembling the various subsystems into the exposure apparatus include, for example, the mechanical connection, the wiring connection of the electric circuits, the piping connection of the air pressure circuits, and the like in correlation with the various subsystems. It goes without saying that the steps of assembling the respective individual subsystems are performed before performing the steps of assembling the various subsystems into the exposure apparatus. When the steps of assembling the various subsystems into the exposure apparatus are completed, the overall adjustment is performed to secure the various accuracies as the entire exposure apparatus. It is desirable that the exposure apparatus is produced in a clean room in which, for example, the temperature, the cleanness and the like are managed.

As shown inFIG. 11, the microdevice such as the semiconductor device is produced by performing, for example, a step201of designing the function and the performance of the microdevice, a step202of manufacturing a mask (reticle) based on the designing step, a step203of producing a substrate as a base material for the device, a substrate processing step204of exposing the substrate with a pattern of the mask by the exposure apparatus EX of the embodiment described above and developing the exposed substrate, a step of assembling the device (including a dicing step, a bonding step, and a packaging step)205, an inspection step206, and the like. The substrate processing step204includes the process such as a step of removing the foreign matter and a step of inspecting the foreign matter as explained with reference toFIGS. 5 to 7and12.

INDUSTRIAL APPLICABILITY

According to the present invention, it is possible to realize the liquid immersion exposure in which the substrate is exposed through the liquid. Therefore, it is possible to produce the device having the device pattern in which the resolution and the density are further enhanced.