Patent Publication Number: US-2009237638-A1

Title: Exposure apparatus and device manufacturing method

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an exposure apparatus that exposes a substrate through liquid and a method for manufacturing a device using the exposure apparatus. 
     2. Description of the Related Art 
     Referring to  FIGS. 8A and 8B , existing immersion exposure apparatuses are described. 
       FIGS. 8A and 8B  are schematic sectional views illustrating a state when a periphery of a wafer  40  is exposed to light. In  FIG. 8A , a wafer holding section  802  supports the back side of the wafer  40  on a surface  801  and firmly fixes the wafer  40  by holding the wafer  40  with a vacuum. A support plate  843  is disposed so as to surround the wafer  40 . The height of a surface  843   a  of the support plate  843  is substantially equal to the height of a surface of the wafer  40 . 
     A liquid recovery mechanism is disposed in a lower part of a space  800 . The liquid recovery mechanism includes a recovery port  804 , a recovery pipe  805 , and a suction device  806 . The recovery port  804  serves to drain liquid LW that has dropped into the space  800  as shown in  FIG. 8B . The recovery port  804  is connected to the suction device  806  through the recovery pipe  805 . 
     Japanese Patent Laid-Open No. 2006/186112 describes controlling of spattering and flow of liquid by providing a hydrophilic area on a surface of a support plate. International Publication No. WO 2004/112108 pamphlet and International Publication No. WO 2006/049134 pamphlet describe a liquid recovery mechanism for recovering liquid that has dropped into a gap between the wafer and the support plate. 
     Referring to  FIG. 8A , a first problem with existing immersion exposure apparatuses is described. The first problem is that, when a periphery of the wafer  40  is exposed to light, the liquid may be divided when liquid LW spreads over a gap, and the divided liquid d may spatter in the exposure apparatus when a wafer stage moves. The spattering of liquid may cause corrosion of peripheral components, or may form water marks and stain the exposure apparatus. To address the problem, the surface  843   a  of the support plate may be made hydrophilic so as to retain liquid d on the surface  843   a  and suppress spattering of liquid d in the exposure apparatus. With this method, however, it is difficult to recover liquid d from the surface  843   a  that is hydrophilic, and watermarks may be formed on the surface  843   a.    
     Referring to  FIG. 8B , a second problem is described. When a periphery of the wafer  40  is exposed to light, liquid LW drops into the space  800  through the gap g between the wafer  40  and the support plate  843 . Then, when the wafer stage is driven, liquid LW may overflow through the gap g, spatter onto the support plate  843  and the wafer  40  and stain the exposure apparatus. This is the second problem. In order to solve the problem, liquid LW in the space  800  may be recovered using the suction device  806  so as to suppress overflow of liquid LW. However, this may accelerate vaporization of liquid LW, which may cause thermal deformation of peripheral components. 
     As heretofore described, it is important to rapidly recover liquid d divided at gap g without allowing the liquid d to spatter in the exposure apparatus, and to prevent liquid LW that has dropped into the space  800  from overflowing when the stage moves. 
     SUMMARY OF THE INVENTION 
     The present invention provides an exposure apparatus with which one or both of the first problem and the second problems is solved and light exposure is performed with excellent precision. 
     According to an aspect of the present invention, an exposure apparatus for exposing a substrate through liquid includes a stage for holding and moving the substrate. The stage includes a holding section for holding the substrate and a supporting section disposed around the holding section. The supporting section includes a recovery port including a gap between the substrate held by the holding section and the supporting section, the recovery port for recovering the liquid, a space for storing the liquid recovered through the recovery port, a liquid recovery mechanism for draining the liquid that has collected in a lower part of the space, and a sloshing reduction member disposed in the space, the sloshing reduction member for reducing sloshing of the liquid. 
     Further aspects of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a schematic sectional view of a periphery of a wafer for describing a first embodiment of the present invention. 
         FIG. 1B  is a schematic sectional view of the periphery of the wafer for describing the first embodiment. 
         FIG. 1C  is a schematic sectional view of the periphery of the wafer for describing the first embodiment. 
         FIG. 2  is a schematic sectional view of an exposure apparatus. 
         FIG. 3  is a schematic view for explaining an equation of motion for liquid LW. 
         FIG. 4  is a graph showing a relationship between hydraulic conductivity and rise value of liquid. 
         FIG. 5  is a schematic sectional view of a periphery of a wafer for describing a second embodiment of the present invention. 
         FIG. 6A  is a schematic sectional view of a periphery of a wafer for describing a third embodiment of the present invention. 
         FIG. 6B  is a schematic sectional view of the periphery of the wafer for describing the third embodiment. 
         FIG. 7  is a schematic perspective view of a periphery of a wafer for describing a fourth embodiment of the present invention. 
         FIG. 8A  is a schematic sectional view of a periphery of a wafer for describing conventional arts. 
         FIG. 8B  is a schematic sectional view of the periphery of the wafer for describing conventional arts. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, various embodiments of the present invention are described in detail with reference to the attached drawings. 
       FIG. 2  is a schematic sectional view showing a structure of an exposure apparatus  1  according to a first embodiment of the present invention. 
     The exposure apparatus  1  is an immersion exposure apparatus that exposes a pattern of a reticle (mask)  20  onto a wafer  40  through liquid (immersion liquid) LW that is supplied between a final surface  30   a  of a projection optical system  30  and the wafer  40 . The exposure apparatus  1  exposes the wafer  40  to light by a step-and-scan method. However, an exposure apparatus that exposes the wafer  40  to light by a step-and-repeat method can also be used. 
     As shown in  FIG. 2 , the exposure apparatus  1  includes an illumination unit  10 , a reticle stage  21 , the projection optical system  30 , a wafer stage  41 , a support plate (supporting section)  43 , and a distance measuring unit  50 . 
     The illumination unit  10  includes a light source  11  and an illumination optical system  12 . In this embodiment, ArF excimer lasers with a wavelength of 193 nm are used as the light source  11 . However, KrF excimer lasers of a wavelength of about 248 nm or F 2  lasers with a wavelength of about 157 nm can be used as the light source  11 . The illumination optical system  12  illuminates the reticle  20  with light from the light source  11 . 
     The reticle stage  21  is mounted on a base  22  for fixing the reticle stage  21 . The reticle stage  21  holds the reticle  20  with a reticle chuck (not shown). The reticle stage  21  is controlled by a movement mechanism (not shown) and a control unit described below. The reticle  20 , which is made of quartz, is an original having a circuit pattern formed thereon. Diffracted light that has passed through the circuit pattern of the reticle  20  is projected onto the wafer  40  with the projection optical system  30 . 
     The projection optical system  30  projects the pattern of the reticle  20  onto the wafer  40 . A dioptric system or a catadioptric system can be used for the projection optical system  30 . 
     The wafer stage  41  is mounted on a base  42  for fixing the wafer stage  41 . The wafer stage  41  holds the wafer  40  on a wafer holding section. The wafer stage  41  functions to adjust the up-and-down (vertical) position, the orientation, and the inclination of the wafer  40 . The wafer stage  41  is controlled by a stage control unit. While the wafer  40  is being exposed to light, the stage control unit controls the wafer stage  41  so that the focal plane of the projection optical system  30  coincides with the upper surface of the wafer  40  with high precision. The wafer  40  is conveyed into the exposure apparatus  1  with a wafer conveying system (not shown). The wafer  40  is supported on and moved with the wafer stage  41 . Although the wafer  40  is used as a substrate in this embodiment, a liquid crystal substrate or the like can be also used as the substrate. The wafer  40  is coated with a photoresist. 
     The support plate  43  surrounds the wafer  40 . The height of the upper surface of the support plate  43  is adjusted so as to be substantially the same height as the upper surface of the wafer  40 . The support plate  43  and the wafer  40  support the liquid LW when an edge of the wafer  40  is exposed to light. 
     The distance measuring unit  50  measures in real time the position of the reticle stage  21  and the three-dimensional position of the wafer stage  41  using reference mirrors  51  and  52  and laser interferometers  53  and  54 . Measurements made by the distance measuring unit  50  are transmitted to a control unit  130  described below. The reticle stage  21  and the wafer stage  41  are driven and positioned under control by the control unit  130 . 
     The liquid LW can be selected, for example, from substances having a low absorptance for the light used for exposure and having a refractive index as high as possible. As more specific examples, pure water, functional water, a fluoridized liquid (for example, a fluorocarbon), an organic liquid, or the like may is used as the liquid LW. Dissolved gas in the liquid LW can be sufficiently removed using a degassing apparatus. As the liquid LW, liquid including water with a very small amount of additives or hydrocarbon organic liquid can also be used. 
     The exposure apparatus  1  further includes a supply/recovery unit  110  and the control unit  130 . 
     The supply/recovery unit  110  supplies the liquid LW to and recovers the liquid LW from between the wafer  40  and the final surface  30   a  of the projection optical system  30  through a supply pipe  111 , a recovery pipe  112 , a supply nozzle  113 , and a recovery nozzle  114 . The supply/recovery unit  110 , which has a structure for supplying and recovering the liquid LW, is controlled by the control unit  130 . The supply/recovery unit  110  also supplies and recovers the liquid LW when the wafer stage  41  moves. With the above-described structure, the supply/recovery unit  110  can remove dissolved gas and impurities from the liquid LW, and the liquid LW is maintained in a homogeneous state. 
     The control unit  130 , which includes a CPU (not shown) and a memory, controls the exposure apparatus  1 . The control unit  130  is electrically connected to the illumination unit  10 , the movement mechanism (not shown) for the reticle stage  21 , a movement mechanism (not shown) for the wafer stage  41 , and the supply/recovery unit  110 . For example, the control unit  130  may be configured to supply and recover the liquid LW by switching the flow direction of the liquid LW in accordance with the wafer stage  41  when light exposure is performed. Alternatively, the control unit  130  may be configured to supply and recover the liquid LW in a constant amount when light exposure is performed. 
     Referring to  FIGS. 1A to 1C , a method for recovering liquid d that has been divided and a method for suppressing an overflow of the liquid LW that has dropped into a space  100  in this embodiment is described below.  FIGS. 1A to 1C  are schematic sectional views of a periphery of the wafer  40  for describing the first embodiment. 
     First, a structure around the periphery of the wafer  40  in this embodiment is described. A surface of the support plate  43  includes a first area  43   a  that is hydrophilic and a second area  43   b  that is hydrophobic (liquid-repellent). The first area  43   a  is made of hydrophilic material (for example, SiO2, SiC, or a metal oxide such as titanium oxide). Lateral sides of the first area are also hydrophilic. The first area  43   a  surrounds the wafer  40 . The first area  43   a  has a width w in the range of several millimeters to several tens of millimeters. The width of a gap g between the wafer  40  and the first area  43   a  is adjusted so as to be approximately between 0.1 mm to 2 mm. The second area  43   b  surrounds the first area  43   a.  A gap g 2  is formed between the first area  43   a  and the second area  43   b.  The second area  43   b  is coated with Teflon or treated by a hydrophobic treatment such as PFA. 
     The gap g 2  and the gap g provide recovery ports  109  for recovering the liquid d and allow the liquid d to be recovered from the surface of the support plate  43  to the space  100  therethrough. A side surface  43   c  of the support plate  43  is made hydrophilic so that the liquid d can be smoothly recovered to the space  100 . As hydrophilic treatment, titanium oxide coating, for example, can be used. Moreover, a side surface of the wafer  40  and a side surface  802   a  of the wafer holding section  802  may be made hydrophilic. Furthermore, the liquid d can be recovered more effectively by disposing a recovery port for recovering the liquid d in the first area  43   a.  For example, slits, pinholes, or a porous body may be formed in the first area  43   a.    
     The space  100  is formed in the support plate  43  in a ring shape so as to surround the wafer  40  so that liquid recovered through the recovery ports  109  can be temporarily stored therein. 
     A porous body  101 , which serves as a sloshing reduction member, has a ring shape so as to surround the wafer  40  and has a volume equal to or larger than half the volume of the space  100 . In this embodiment, the porous body  101  occupies a space from a space bottom  100   a  to near the first area  43   a.  As the porous body  101 , for example, SiO2, SiC, or a sintered compact of metal such as stainless steel or titanium can be used. Hydraulic conductivity is an indicator of the permeability of a porous body. Hydraulic conductivity is a coefficient defined by Darcy&#39;s law expressed by equation 1. Here, v is apparent seepage flow velocity (cm/sec), k is hydraulic conductivity (cm/sec), and i is hydraulic gradient. 
       v=ki   (1) 
     The porous body  101  in this embodiment has a hydraulic conductivity equal to or lower than 1000 cm/sec for the reasons described below. 
     A liquid recovery mechanism  104  is a mechanism for draining liquid that has collected in the space  100 . In this embodiment, the liquid recovery mechanism  104  includes a groove  102  and pinholes  103  disposed in the lower part of the space  100 . The groove  102 , which is formed in the space bottom  100   a,  has a ring shape so as to surround the wafer  40 . The groove  102  serves to guide the liquid LW that has infiltrated into the porous body  101  to the pinholes  103 . The pinholes  103  have a diameter in the range from several hundred micrometers to several tens of millimeters. The pinholes  103  are disposed in the groove  102 . In this embodiment, the pinholes  103  are disposed at equally spaced intervals along the circumference of the wafer  40 . The groove  102  is not necessary when a large number of the pinholes  103  are provided, because the liquid LW that has infiltrated into the porous body  101  is easily drained to the pinholes  103  in this case. The liquid recovery mechanism  104  is disposed near the center of the space bottom  100   a  or below the recovery ports  109 . In order to effectively drain the liquid LW, the space bottom  100   a  may be inclined downward toward the liquid recovery mechanism  104 . 
     As shown in  FIG. 1B , the liquid recovery mechanism  104  may be disposed in the side surface  43   c  of the support plate  43 . Because the liquid LW is collected on the space bottom  100   a  by gravitation, the liquid LW can be drained as in the configuration shown in  FIG. 1A . 
     A recovery pipe  105  guides liquid from the liquid recovery mechanism  104  to a suction device  108 . The suction device  108  includes a gas-liquid separation unit  106  and a decompressor  107 . 
     Next, some of the advantages of this embodiment are described. 
     While a periphery of the wafer  40  is being exposed to light (edge shot), liquid may be divided when an immersion area spreads over the gap g. However, in this embodiment, the liquid d that has been divided remains on the first area  43   a  because the first area  43   a  is hydrophillic, whereby spattering of the liquid d is reduced. Therefore, corrosion of peripheral components and formation of water marks resulting from spattering of the liquid d can be reduced. 
     Moreover, the liquid d on the first area  43   a  is drained to the space  100  through the recovery ports  109 . Therefore, evaporation of the liquid d on the first area  43   a  and the formation of water marks resulting therefrom can be reduced. 
     Although the first area  43   a  is made hydrophilic in this embodiment, the first area  43   a  may be made hydrophobic in a case when liquid is not divided or in a case when only a small amount of liquid is divided. In this case, the contact angle between the first area  43   a  and the surface of liquid is equal to the contact angle between the second area  43   b  and the surface of liquid. Moreover, the surface of the support plate  43  may be constituted by a single region without the gap g 2 . 
     As shown in  FIG. 1C , in the case when only a small amount of liquid is divided, the first area  43   a  that is hydrophilic and the second area  43   b  that is hydrophobic may be formed continuously. Although the gap g 2  is not provided in this case, the liquid d on the hydrophilic first area  43   a  can be sufficiently recovered through a gap g 1 , since the amount of the liquid d is small. For example, the first area  43   a  and the second area  43   b  of the support plate  43  may be integrally formed from a hydrophilic material such as SiC, and only the second area  43   b  may be treated by hydrophobic treatment with Teflon (registered trademark) or the like. By integrally forming the first area  43   a  and the second area  43   b,  formation of a difference in height or a gap between the first area  43   a  and the second area  43   b  can be prevented, whereby the state of the liquid LW can be maintained stably when the wafer stage  41  moves at a higher velocity. 
     The liquid LW enters from the recovery ports  109 , passes through the porous body  101 , and collects in the space  100 . A material having a sufficiently high permeability is used for the porous body  101 . 
     The liquid LW that has collected in the space  100  may overflow through the recovery ports  109  when the wafer stage  41  moves. However, sloshing of the liquid LW is reduced in this embodiment since the porous body  101  is disposed in the space  100 . As a result, overflow of the liquid LW from the recovery ports  109  can be reduced. Actually, overflow of the liquid LW is reduced when hydraulic conductivity of the porous body  101  is equal to or less than  1000  cm/sec. In particular, it is beneficial to reduce overflow of the liquid LW for this embodiment, because the liquid easily drops into the space  100  since the first area  43   a  is hydrophilic. 
     Next, referring to equations 2 to 5 and  FIGS. 3 and 4 , measures for reducing overflow of the liquid LW are described. 
     When the Z coordinate is taken as shown in  FIG. 3 , the equation of motion for the liquid LW using hydraulic conductivity can be expressed by equation 2. The solution to this equation of motion is given by equation 3. 
     
       
         
           
             
               
                 
                   
                     
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             z(t) [m]: Vertical position of liquid LW 
             ρ [kg/m 3 ]: Density of liquid 
             g: Acceleration of gravity 9.8 m/s 2    
             k [cm/s]: Hydraulic conductivity 
           
         
       
    
     
       
         
           
             
               
                 
                   
                     
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     Here, maximum value of Z is expressed by equation 4. The maximum rise value Δz of the liquid LW resulting from sloshing of the liquid caused by the movement of the wafer stage  41  is expressed by equation 5. 
     
       
         
           
             
               
                 
                   
                     
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     The relation between hydraulic conductivity k and a rise value of the liquid Δz is illustrated in the graph of  FIG. 4 . Δz is a value obtained by normalizing the rise value of the liquid LW (maximum value of z−initial value of z) [m] with the rise value of the liquid LW (maximum value of z−initial value of z)=v 0   2 /(2 g) [m] when the porous body  101  is not present (corresponding to k=∞). Here, the initial velocity v 0  is set to be 1 m/s, because v 0  is at most comparable to the velocity of the movement of the wafer stage  41 . It can be seen from  FIG. 4  that the rise of the liquid LW is effectively reduced when the hydraulic conductivity of the porous body is lower than 1000 cm/s. 
     In this embodiment, it is not necessary to continuously suck and recover the liquid LW through the liquid recovery mechanism  104 , because the liquid LW collected in the space  100  does not overflow. For example, suction recovery of the liquid LW may be stopped by closing a valve  105   a  shown in  FIGS. 1A and 1B  while the wafer  40  is being exposed to light, and suction recovery of the liquid LW may be restarted by opening the valve  105   a  after light exposure (when light exposure is not performed). Alternatively, the power of suction recovery may be reduced during light exposure and increased after light exposure (when light exposure is not performed). As a result, the influence of heat of vaporization resulting from suction recovery can be reduced during light exposure. 
     As heretofore described, since the exposure apparatus  1  of this embodiment has the first area  43   a  that is hydrophilic and the recovery ports  109  on the surface of the support plate  43 , the liquid d can be recovered to the space  100  without allowing the liquid d to spatter in the exposure apparatus  1 . Moreover, since the porous body  101  is disposed in the space  100 , the liquid LW is prevented from overflowing from the space  100  as the stage moves. As a result, corrosion of components near the wafer and formation of water marks can be suppressed, and staining of the exposure apparatus  1  can be reduced. Moreover, since it is not necessary to constantly suck the liquid that has collected in the space  100 , heat of vaporization can be reduced, whereby decline of exposure accuracy caused by the heat of vaporization can be suppressed. 
     Referring to  FIG. 5 , a second embodiment of the present invention is described below.  FIG. 5  is a schematic sectional view of the periphery of the wafer  40  corresponding to  FIGS. 1A and 1C . In the following description, the same numerals are used for the components that are the same as or similar to those in the first embodiment, and redundant description of such components is avoided. 
     In  FIG. 5 , a porous body  501  having a thickness of several millimeters is disposed in the upper part of the space  100  so as to serve as a sloshing reduction member. To be specific, the porous body  501  is disposed in the upper half of the space  100  in this embodiment. Liquid d is drained through the recovery ports  109 , passes through the porous body  501 , and is recovered to the space bottom  100   a.  Sloshing of the liquid LW caused by the movement of the wafer stage  41  is reduced with the porous body  501 . As a result, the liquid LW does not overflow from the recovery ports  109 . It is beneficial that the hydraulic conductivity of the porous body  501  be higher than 1000 cm/sec for the above-described reason. The liquid LW that has collected on the space bottom  100   a  is recovered to the recovery pipe  105  through the liquid recovery mechanism  104 . 
     Although the porous body  501  is used as a sloshing reduction member in the foregoing description, a porous plate having pinholes therein can also be used as a sloshing reduction member. The porous plate has a thickness of several millimeters, and the diameter of the pinholes is in the range from several hundred micrometers to several millimeters. By treating the porous plate by hydrophilic treatment, liquid can be easily drained to the space  100  through the pinholes. 
     As described above, since an exposure apparatus of this embodiment has a porous body or a porous plate as a sloshing reduction member in the upper part of the space  100 , liquid d can be recovered through the recovery ports  109  and sloshing of the liquid LW in the space  100  can be reduced. As a result, the liquid LW is prevented from overflowing from the recovery ports  109 , and spattering of liquid in the exposure apparatus can be suppressed. 
     Referring to  FIGS. 6A and 6B , a third embodiment of the present invention is described below.  FIGS. 6A and 6B  are schematic sectional views corresponding to  FIGS. 1A to 1C . In the following description, the same numerals are used for the components that are the same as or similar to those in the first embodiment, and redundant description of such components is avoided. 
     As shown in  FIG. 6A , in this embodiment, plates  602  having pinholes  601  are disposed in the space  100  in a multi-tiered manner so as to serve as a sloshing reduction member. The diameter of the pinholes  601  is in the range of several hundred micrometers to several of millimeters. Although the number of plates  602  is three in this embodiment, the number of plates  602  can be reduced by reducing the diameter of the pinholes  601 . The number of plates  602  may be appropriately set in accordance with the diameter of the pinholes  601 . Liquid d is recovered through the recovery ports  109  and collects in the space  100  through the pinholes  601  of the plates  602 . When the wafer stage  41  moves, sloshing of liquid is suppressed with the multi-tiered plates  602 , whereby overflow of the liquid through the recovery ports  109  is suppressed. By positioning the pinholes  601  of vertically adjacent plates  602  in a staggered manner, sloshing of liquid LW can be effectively suppressed. The diameter of the pinholes  601  may become smaller from the upper plates to the lower plates. 
     In the foregoing description, the plates  602  with the pinholes  601  are used as multi-tiered plates so as to reduce sloshing of liquid. However, as shown in  FIG. 6B , openings  603  may be formed between the plates  602  and the support plate  43 , or between the plates  602  and the wafer holding section  802 . In this case, since the positions of the openings  603  formed with vertically adjacent plates  602  are staggered, sloshing of liquid LW can be suppressed effectively. 
     In this embodiment, the plates  602  may be hydrophilic. In this case, liquid d recovered through the recovery ports  109  can be quickly drained to the lower part of the space  100 . 
     As heretofore described, since the exposure apparatus of this embodiment has the multi-tiered plates  602  with openings in the space  100  as a sloshing reduction member, liquid d can be recovered through the recovery ports  109  and sloshing of liquid LW in the space  100  can be reduced. As a result, overflow of liquid LW through the recovery ports  109  and spattering of liquid LW in the exposure apparatus can be suppressed. 
     Referring to  FIG. 7 , a fourth embodiment of the present invention is described below.  FIG. 7  is a schematic perspective view corresponding to  FIGS. 1A to 1C . In the following description, the same numerals are used for the components that are the same as or similar to those in the first embodiment, and redundant description of such components is avoided. 
     In this embodiment, partition plates  701  serving as a sloshing reduction member divides the space  100  into a plurality of spaces  702 . As shown in  FIG. 7 , the partition plates  701  are disposed in the radial direction and the circumferential direction. The number of partition plates  701  may be determined appropriately in accordance with the viscosity of liquid LW and dimensions of the wafer stage  41  and the space  100 . A gap  703  is formed between the partition plates  701  and the space bottom  100   a.  The size of the gap  703  is in the range from several hundred micrometers to several millimeters. With this structure, liquid d is recovered through the recovery ports  109  and collects in the space  100  through the divided spaces  702 , whereby the liquid can spread all over the lower part of the space  100 . As a result, the liquid recovery mechanism  104  can recover the entire liquid d in the space  100  through the groove  102 . Because the partition plates  701  are hydrophilic, liquid d can be recovered rapidly. 
     When the wafer stage  41  moves, the partition plates  701  serve to reduce sloshing of the liquid and suppress overflow of the liquid through the recovery ports  109 . 
     Although the partition plates  701  are disposed in the radial direction and the circumferential direction of the wafer  40  in this embodiment, the partition plates  701  may be disposed in only one of the directions. It is not necessary that the partition plates  701  be disposed in the radial direction or in the circumferential direction as long as the space  100  is divided into a plurality of spaces. 
     As heretofore described, since the exposure apparatus of this embodiment has the partition plates  701  serving as a sloshing reduction member in the space  100 , liquid d can be recovered through the recovery ports  109 , and sloshing of liquid LW in the space  100  can be reduced. As a result, overflow of liquid LW through the recovery ports  109  and spattering of liquid LW in the exposure apparatus can be suppressed. 
     Next, a method for manufacturing a device (semiconductor device, liquid crystal display device, or the like) according to another embodiment of the present invention is described. A method for manufacturing a semiconductor device is used as an example here. 
     A semiconductor device is manufactured by a front-end process by which an integrated circuit is formed on a wafer and a back-end process by which chips of the integrated circuit formed by the front-end process are finished into a product. The front-end process includes a process for exposing a substrate coated with a photoresist to light using any of the above-described exposure apparatuses of the present invention and a process for developing the substrate. The back-end process includes an assembly process (dicing and bonding) and a packaging process. 
     With the device manufacturing method of this embodiment, a device having a quality higher than the existing device can be manufactured. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. This application claims the benefit of Japanese Patent Application No. 2008-076891 filed Mar. 24, 2008 and No. 2009-016217 filed Jan. 28, 2009, which are hereby incorporated by reference herein in their entirety.