JP2004207710A - Exposure system, exposure method, and device-manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid immersion exposure system which exposes a substrate with proper pattern transfer accuracy, when exposure treatment is conducted between a projection lens system and the substrate with a liquid filled up. <P>SOLUTION: The exposure system EX fills a space between the projection lens system PL and the substrate P up with the liquid 50, and the substrate P is exposed by the projection lens system PL, by projecting an image of the pattern on the substrate P via the liquid 50. A substrate stage PST to support the substrate P, a liquid-supplying apparatus 1 to supply the liquid 50 to an image face side of the projection lens system PL, and a focus-leveling detection system 14 to detect an face information of the surface of the substrate P, without going through the intermediary the liquid 50 via are provided. The exposure system EX achieves liquid immersion exposure; while adjusting a position relation of the surface of the substrate P to the image face formed via the projection lens system PL and the liquid 50, based on the face information detected at the focus leveling detection system 14. The liquid immersion exposure is conducted with proper pattern transfer accuracy. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention provides an immersion exposure apparatus and an immersion exposure method for exposing with an image of a pattern projected by the projection optical system in a state where at least a portion between the projection optical system and the substrate is filled with a liquid, and the exposure apparatus. The present invention relates to a device manufacturing method to be used.

A semiconductor device and a liquid crystal display device are manufactured by a so-called photolithography technique of transferring a pattern formed on a mask onto a photosensitive substrate. The exposure apparatus used in this photolithography process has a mask stage that supports a mask and a substrate stage that supports a substrate, and sequentially moves the mask stage and the substrate stage to project a pattern of the mask through a projection optical system. This is to be transferred to a substrate. In recent years, further improvement in the resolution of the projection optical system has been desired in order to cope with higher integration of device patterns. The resolution of the projection optical system increases as the exposure wavelength used decreases and as the numerical aperture of the projection optical system increases. For this reason, the exposure wavelength used in the exposure apparatus is becoming shorter year by year, and the numerical aperture of the projection optical system is also increasing. The exposure wavelength currently mainstream is 248 nm of KrF excimer laser, but 193 nm of shorter wavelength ArF excimer laser is also being put to practical use. When performing exposure, the depth of focus (DOF) becomes important as well as the resolution. The resolution R and the depth of focus δ are respectively represented by the following equations.
R = k ₁ · λ / NA (1)
δ = ± k ₂ · λ / NA ² (2)
Here, λ is the exposure wavelength, NA is the numerical aperture of the projection optical system, and k ₁ and k ₂ are the process coefficients. From the expressions (1) and (2), it can be seen that when the exposure wavelength λ is shortened and the numerical aperture NA is increased in order to increase the resolution R, the depth of focus δ becomes narrower.

If the depth of focus δ becomes too narrow, it becomes difficult to match the substrate surface with the image plane of the projection optical system, and the focus margin during the exposure operation may be insufficient. Therefore, as a method of substantially shortening the exposure wavelength and widening the depth of focus, for example, a liquid immersion method disclosed in International Publication WO99 / 49504 has been proposed. In this immersion method, the space between the lower surface of the projection optical system and the substrate surface is filled with a liquid such as water or an organic solvent, and the wavelength of the exposure light in the liquid is 1 / n (n is the refraction of the liquid) in the air. The ratio is usually about 1.2 to 1.6), thereby improving the resolution and expanding the depth of focus to about n times.
WO 99/49504 pamphlet

  In the above-described exposure apparatus, the detection light is projected onto the substrate surface during the exposure of the substrate, and the reflected light is received to detect the substrate surface position. Based on the detection result, the detection light is formed through the projection optical system. The positional relationship between the pattern image plane to be formed and the substrate surface is appropriately adjusted. However, in an immersion exposure apparatus based on the immersion method, a liquid exists between the projection optical system and the substrate, and the surface position of the substrate surface can be accurately detected under the influence of a change in the temperature of the liquid. Therefore, the adjustment of the positional relationship between the pattern image plane and the substrate surface may not be properly performed. Similarly, if the alignment mark on the substrate is detected through the liquid, the mark on the substrate cannot be detected accurately due to the influence of the temperature change of the liquid, etc., and the alignment between the mask and the substrate will be accurate. May not be done.

  The present invention has been made in view of such circumstances, and when performing an exposure process in a state where a liquid is filled between a projection optical system and a substrate, the liquid immersion that can expose the substrate with good pattern transfer accuracy is performed. An object of the present invention is to provide an exposure apparatus and an immersion exposure method. It is another object of the present invention to provide an immersion exposure apparatus and an immersion exposure method that can adjust the positional relationship between the substrate surface and the pattern image plane to an optimal state. It is another object of the present invention to provide an immersion exposure apparatus and an immersion exposure method that can accurately perform substrate alignment (alignment).

  In order to solve the above-described problem, the present invention employs the following configuration corresponding to FIGS. However, the parenthesized code given to each element is only an example of the element, and there is no intention to limit each element.

  According to a first aspect of the present invention, there is provided an exposure apparatus for transferring an image of a pattern onto a substrate (P) via a liquid (50) and exposing the substrate, wherein the projection apparatus projects the image of the pattern onto the substrate. An optical system (PL), a first substrate stage (PST) for holding a substrate (P), a liquid supply device (1) for supplying a liquid (50) to the image plane side of the projection optical system (PL), and a substrate (P) a surface detection system (14) for detecting surface information of the surface without passing through the liquid (50), and based on the detected surface information, a surface of the substrate (P) and a projection optical system (PL). An exposure apparatus (EX) for performing immersion exposure of the substrate (P) while adjusting a positional relationship with an image plane formed via the liquid (50).

  According to the present invention, after the surface information of the substrate surface is detected without passing through the liquid for immersion exposure, the immersion exposure is performed based on the information, so that the immersion exposure is affected by the temperature change of the liquid. Instead, the adjustment of the positional relationship between the substrate surface and the image plane formed via the liquid, and the alignment of each shot area on the substrate with the projection position of the pattern image can be performed accurately. Further, there is no need to configure the alignment system for liquid immersion, and the conventional detection system can be used as it is.

  According to a second aspect of the present invention, a plurality of shots on the substrate are sequentially exposed to a plurality of shot areas (S1 to S20) on the substrate (P) via the liquid (50). An exposure apparatus for exposing an area, comprising: a projection optical system (PL) for projecting a pattern image onto a substrate; a first substrate stage (PST) for holding the substrate (P); and an image of the projection optical system (PL). A liquid supply device (1) for supplying a liquid (50) to the surface side; and a first alignment system (18) for detecting an alignment mark on the substrate (P) without passing through the liquid (50). An exposure apparatus (EX) for performing immersion exposure of a substrate (P) while performing alignment between a substrate (P) and a pattern based on a detection result of one alignment system (18).

  According to the present invention, after the alignment mark on the substrate is detected without the intervention of the liquid for immersion exposure, the immersion exposure is performed based on the information, so that the exposure apparatus is the same as the exposure apparatus of the first aspect. Adjustment of the positional relationship between the substrate surface and the image plane formed via the liquid, and alignment of each shot area on the substrate with the projection position of the pattern image without being affected by changes in the temperature of the liquid Can be performed accurately. Further, there is no need to configure the alignment system for liquid immersion, and the conventional detection system can be used as it is.

  According to the present invention, there is provided a device manufacturing method using the exposure apparatus of the above aspect.

  According to a third aspect of the present invention, there is provided an immersion exposure method for exposing a substrate by transferring an image of a pattern onto a substrate (P) via a liquid (50), wherein the substrate is exposed to light. A step (S2, S4) of obtaining surface information of the substrate surface by measurement not via the supplied liquid; a step (S5) of supplying a liquid onto the substrate; and a step (S5) of obtaining the substrate information based on the obtained surface information. There is provided an immersion exposure method including a step (S8) of performing immersion exposure on the substrate while adjusting a positional relationship between a surface and an image surface formed via the liquid. According to this method, since the surface information of the substrate surface is obtained by measurement that does not pass through the liquid, it is possible to accurately and easily execute the positioning of the substrate without being affected by physical changes such as the temperature of the liquid. Can be.

  According to a fourth aspect of the present invention, there is provided an immersion exposure method for exposing a substrate (P) by transferring an image of a pattern onto a substrate via a liquid (50), wherein the liquid is supplied onto the substrate. Detecting the alignment mark on the substrate when not being performed (S1), supplying the liquid onto the substrate (S5), and detecting the alignment mark on the substrate based on the detection result of the alignment mark. An immersion exposure method is provided which includes a step (S8) of immersion exposure of the substrate while performing alignment between the substrate and the pattern. According to this method, the alignment of the shot area of the substrate is performed in a state where the liquid is not interposed (dry condition), so that the alignment is performed accurately and easily without being affected by a physical change such as the temperature of the liquid used for the immersion exposure. The positioning of the shot area of the substrate can be executed. On the other hand, since the exposure operation is performed in a state where the liquid is supplied (wet condition), exposure with a wide depth of focus can be performed. Further, since a conventional apparatus can be used for the alignment system, an increase in apparatus cost due to immersion exposure can be suppressed.

  The immersion exposure apparatus and the immersion exposure method of the present invention detect surface information of a substrate surface or an alignment mark on the substrate without using a liquid for immersion exposure, and then, based on the information. Since the liquid immersion exposure is performed, the positional relationship between the substrate surface and the image plane formed via the liquid can be adjusted, and the position between each shot area on the substrate and the projection position of the pattern image can be accurately adjusted. . Therefore, a precise exposure process can be performed, and a device exhibiting desired performance can be manufactured.

  Hereinafter, an exposure apparatus and a device manufacturing method of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of the exposure apparatus of the present invention.

  1, an exposure apparatus EX includes a mask stage MST that supports a mask M, a substrate stage PST that supports a substrate P, and an illumination optical system IL that illuminates the mask M supported by the mask stage MST with exposure light EL. A projection optical system PL for projecting and exposing an image of the pattern of the mask M illuminated by the exposure light EL onto a substrate P supported on a substrate stage PST, and a control device CONT for controlling the overall operation of the exposure apparatus EX. It has.

  Here, in the present embodiment, the exposure apparatus EX scans the mask M and the substrate P synchronously in directions different from each other in the scanning direction (opposite directions) while exposing the pattern formed on the mask M to the substrate P. An example in which an apparatus (a so-called scanning stepper) is used will be described. In the following description, the direction that coincides with the optical axis AX of the projection optical system PL is the Z-axis direction, the synchronous movement direction (scanning direction) between the mask M and the substrate P in a plane perpendicular to the Z-axis direction is the X-axis direction, A direction perpendicular to the Z-axis direction and the Y-axis direction (non-scanning direction) is defined as a Y-axis direction. In addition, directions around the X axis, the Y axis, and the Z axis are defined as θX, θY, and θZ directions, respectively. Here, the “substrate” includes a semiconductor wafer coated with a resist, and the “mask” includes a reticle on which a device pattern to be reduced and projected onto the substrate is formed.

The illumination optical system IL illuminates the mask M supported by the mask stage MST with the exposure light EL, and includes an exposure light source, an optical integrator for equalizing the illuminance of a light beam emitted from the exposure light source, and an optical integrator. A condenser lens, a relay lens system, and a variable field stop for setting an illumination area on the mask M by the exposure light EL in a slit shape. A predetermined illumination area on the mask M is illuminated by the illumination optical system IL with exposure light EL having a uniform illuminance distribution. The exposure light EL emitted from the illumination optical system IL includes, for example, ultraviolet bright lines (g-line, h-line, i-line) emitted from a mercury lamp and far ultraviolet light (KrF excimer laser light (wavelength: 248 nm)). DUV light) and, ArF excimer laser light (wavelength 193 nm) and _{F 2} laser beam (wavelength 157 nm) vacuum ultraviolet light (VUV light) and the like. In this embodiment, ArF excimer laser light is used.

  The mask stage MST supports the mask M, and is two-dimensionally movable in a plane perpendicular to the optical axis AX of the projection optical system PL, that is, in an XY plane, and is capable of minute rotation in the θZ direction. The mask stage MST is driven by a mask stage driving device MSTD such as a linear motor. The mask stage driving device MSTD is controlled by the control device CONT. The movable mirror 56 is provided on the mask stage MST. A laser interferometer 57 is provided at a position facing the movable mirror 56. The two-dimensional position and rotation angle of the mask M on the mask stage MST are measured in real time by the laser interferometer 57, and the measurement result is output to the control unit CONT. The control device CONT drives the mask stage driving device MSTD based on the measurement result of the laser interferometer 57 to position the mask M supported by the mask stage MST.

  The projection optical system PL projects and exposes the pattern of the mask M onto the substrate P at a predetermined projection magnification β, and is composed of a plurality of optical elements (lenses). These optical elements are mirrors as metal members. It is supported by the cylinder PK. In the present embodiment, the projection optical system PL is a reduction system in which the projection magnification β is, for example, ４ or ５. Note that the projection optical system PL may be either a unity magnification system or an enlargement system. Further, an optical element (lens) 60 is exposed from the lens barrel PK on the distal end side (substrate P side) of the projection optical system PL of the present embodiment. The optical element 60 is provided detachably (exchangeable) with respect to the lens barrel PK.

  The substrate stage (first substrate stage) PST supports the substrate P, and includes a Z stage 51 that holds the substrate P via a substrate holder, an XY stage 52 that supports the Z stage 51, and an XY stage 52. And a base 53 for supporting the The substrate stage PST is driven by a substrate stage driving device PSTD such as a linear motor. The substrate stage driving device PSTD is controlled by the control device CONT.

  Surface information (position information and tilt information in the Z-axis direction) of the surface of the substrate P is detected by a focus / leveling detection system 14 which is a surface detection system. The focus / leveling detection system 14 includes a projection system 14A that projects detection light onto the surface of the substrate P, and a light receiving system 14B that receives light reflected from the substrate P. The detection result of the focus / leveling detection system 14 is output to the control unit CONT. The controller CONT drives the Z stage 51 based on the detection result of the focus / leveling detection system 14 and adjusts the position (focus position) and the tilt angle of the substrate P held on the Z stage 51 in the Z-axis direction. Thereby, the surface of the substrate P is adjusted to an optimum state with respect to the image plane of the projection optical system PL by the autofocus method and the autoleveling method. Note that the Z stage and the XY stage may be formed integrally.

  On the substrate stage PST (Z stage 51), a movable mirror 54 that moves with respect to the projection optical system PL together with the substrate stage PST is provided. A laser interferometer 55 is provided at a position facing the movable mirror 54. The two-dimensional position and the rotation angle of the substrate P on the substrate stage PST are measured in real time by the laser interferometer 55, and the measurement result is output to the control device CONT. The control device CONT drives the XY stage 52 via the substrate stage driving device PSTD based on the measurement result of the laser interferometer 55 to thereby position the substrate P in the XY direction (substantially parallel to the image plane of the projection optical system PL). The position of the substrate P supported by the substrate stage PST is adjusted.

  A substrate alignment system (first alignment system) 18 that detects an alignment mark on the substrate P or a reference mark (described later) provided on the Z stage 51 is arranged near the front end of the projection optical system PL. A mask alignment system (second alignment system) 19 for detecting a reference mark on the Z stage 51 via the mask M and the projection optical system PL is provided near the mask stage MST.

  The configuration of the autofocus / leveling detection system 14 is disclosed, for example, in Japanese Patent Application Laid-Open No. 8-37149 (US Pat. No. 6,195,154). The configuration of the substrate alignment system 18 is disclosed in Japanese Patent Application Laid-Open No. 4-65603 (US Pat. No. 5,493,403). Further, the configuration of the mask alignment system 19 is disclosed in JP-A-7-176468 (US Pat. No. 5,646,413).

  In the present embodiment, the immersion method is applied to improve the resolution by substantially shortening the exposure wavelength and substantially widen the depth of focus. Therefore, at least while the image of the pattern of the mask M is being transferred onto the substrate P, the surface of the substrate P and the tip surface (lower surface) 7 of the optical element (lens) 60 on the substrate P side of the projection optical system PL are connected. A predetermined liquid 50 is filled in between. As described above, the lens 60 is exposed on the distal end side of the projection optical system PL, and the liquid 50 is supplied so as to contact only the lens 60. This prevents corrosion of the lens barrel PK made of metal. In the present embodiment, pure water is used for the liquid 50. The pure water is used not only for the ArF excimer laser light but also for the exposure light EL as far ultraviolet rays such as ultraviolet bright lines (g line, h line, i line) emitted from a mercury lamp and KrF excimer laser light (wavelength 248 nm). Even when light (DUV light) is used, the exposure light EL can be transmitted.

  The exposure apparatus EX is a liquid supply device that supplies a predetermined liquid 50 to a space 56 between the front end surface (the front end surface of the lens 60) 7 of the projection optical system PL and the substrate P, that is, the image plane side of the projection optical system PL. 1 and a liquid recovery device 2 that recovers the liquid 50 in the space 56. The liquid supply device 1 is for filling at least a part between the projection optical system PL and the substrate P with the liquid 50, and includes a tank for accommodating the liquid 50, a pressure pump, and the like. One end of a supply pipe 3 is connected to the liquid supply device 1, and a supply nozzle 4 is connected to the other end of the supply pipe 3. The liquid supply device 1 supplies the liquid 50 to the space 56 via the supply pipe 3 and the supply nozzle 4.

  The liquid recovery device 2 includes a suction pump, a tank for storing the recovered liquid 50, and the like. One end of a recovery pipe 6 is connected to the liquid recovery apparatus 2, and a recovery nozzle 5 is connected to the other end of the recovery pipe 6. The liquid recovery device 2 recovers the liquid 50 in the space 56 via the recovery nozzle 5 and the recovery pipe 6. When the space 56 is filled with the liquid 50, the control device CONT drives the liquid supply device 1 to supply a predetermined amount of the liquid 50 per unit time to the space 56 via the supply pipe 3 and the supply nozzle 4. The recovery device 2 is driven to recover a predetermined amount of the liquid 50 per unit time from the space 56 via the recovery nozzle 5 and the recovery pipe 6. Thereby, the liquid 50 is held in the space 56 between the front end surface 7 of the projection optical system PL and the substrate P. The temperature of the liquid 50 is set, for example, to the same level as the temperature in the chamber in which the exposure apparatus EX is housed.

  FIG. 2 is a partially enlarged view of FIG. 1 showing the lower part of the projection optical system PL of the exposure apparatus EX, the liquid supply device 1, the liquid recovery device 2, and the like. In FIG. 2, the lens 60 at the lowermost end of the projection optical system PL is formed in a rectangular shape elongated in the Y-axis direction (non-scanning direction) except for a portion required for the tip 60A in the scanning direction. At the time of scanning exposure, a part of the pattern image of the mask M is projected onto a rectangular projection area immediately below the tip portion 60A, and the mask M is moved to the projection optical system PL at a speed V in the -X direction (or + X direction). In synchronization with the movement, the substrate P moves in the + X direction (or -X direction) at a speed β · V (β is a projection magnification) via the XY stage 52. Then, after the exposure of one shot area is completed, the next shot area is moved to the scanning start position by the stepping of the substrate P, and thereafter, the exposure processing for each shot area is sequentially performed by the step-and-scan method. In this embodiment, the liquid 50 is set to flow along the moving direction of the substrate P.

  FIG. 3 shows a front end portion 60A of a lens 60 of the projection optical system PL, a supply nozzle 4 (4A to 4C) for supplying the liquid 50 in the X-axis direction, and a collection nozzle 5 (5A, 5B) for collecting the liquid 50. It is a figure which shows the positional relationship of. In FIG. 3, the tip 60A of the lens 60 has a rectangular shape elongated in the Y-axis direction, and the tip 60A of the lens 60 of the projection optical system PL is located on the + X direction side so as to sandwich the tip 60A in the X-axis direction. Two supply nozzles 4A to 4C are arranged, and two recovery nozzles 5A and 5B are arranged on the −X direction side. The supply nozzles 4A to 4C are connected to the liquid supply device 1 via the supply pipe 3, and the recovery nozzles 5A and 5B are connected to the liquid recovery device 2 via the recovery pipe 4. The supply nozzles 8A to 8C and the recovery nozzles 9A and 9B are arranged at positions where the supply nozzles 4A to 4C and the recovery nozzles 5A and 5B are rotated by approximately 180 ° with respect to the center of the tip 60A. The supply nozzles 4A to 4C and the collection nozzles 9A and 9B are alternately arranged in the Y-axis direction, the supply nozzles 8A to 8C and the collection nozzles 5A and 5B are alternately arranged in the Y-axis direction, and the supply nozzles 8A to 8C The liquid supply device 1 is connected via a supply pipe 10, and the recovery nozzles 9 </ b> A and 9 </ b> B are connected to the liquid recovery device 2 via a recovery pipe 11.

  When scanning exposure is performed by moving the substrate P in the scanning direction (-X direction) indicated by the arrow Xa, the supply pipe 3, the supply nozzles 4A to 4C, the recovery pipe 4, and the recovery nozzles 5A and 5B are used. Thus, the liquid supply device 1 and the liquid recovery device 2 supply and recover the liquid 50. That is, when the substrate P moves in the −X direction, the liquid 50 is supplied from the liquid supply device 1 to the space between the projection optical system PL and the substrate P via the supply pipe 3 and the supply nozzles 4 (4A to 4C). At the same time, the liquid 50 is recovered by the liquid recovery device 2 via the recovery nozzle 5 (5A, 5B) and the recovery pipe 6, and the liquid 50 is discharged in the −X direction so as to fill the space between the lens 60 and the substrate P. Flows. On the other hand, when performing scanning exposure by moving the substrate P in the scanning direction (+ X direction) indicated by the arrow Xb, the supply pipe 10, the supply nozzles 8A to 8C, the collection pipe 11, and the collection nozzles 9A and 9B are used. The liquid supply device 1 and the liquid recovery device 2 supply and recover the liquid 50. That is, when the substrate P moves in the + X direction, the liquid 50 is supplied from the liquid supply device 1 to the space between the projection optical system PL and the substrate P via the supply pipe 10 and the supply nozzles 8 (8A to 8C). At the same time, the liquid 50 is recovered by the liquid recovery device 2 via the recovery nozzles 9 (9A, 9B) and the recovery pipe 11, and flows in the + X direction so as to fill the space between the lens 60 and the substrate P. As described above, the control device CONT uses the liquid supply device 1 and the liquid recovery device 2 to flow the liquid 50 in the same direction as the movement direction of the substrate P along the movement direction of the substrate P. In this case, for example, the liquid 50 supplied from the liquid supply device 1 via the supply nozzle 4 flows so as to be drawn into the space 56 as the substrate P moves in the −X direction. The liquid 50 can be easily supplied to the space 56 even if the energy is small. By switching the direction in which the liquid 50 flows in accordance with the scanning direction, the substrate P can be moved in either the + X direction or the −X direction between the tip surface 7 of the lens 60 and the substrate P. Can be filled with the liquid 50, and a high resolution and a wide depth of focus can be obtained.

  The shape of the nozzle described above is not particularly limited. For example, supply or recovery of the liquid 50 may be performed by two pairs of nozzles on the long side of the tip portion 60A. Note that, in this case, the supply nozzle and the recovery nozzle may be arranged vertically so that the supply and recovery of the liquid 50 can be performed from either the + X direction or the −X direction. . Although not shown, nozzles for supplying and recovering the liquid 50 are provided at predetermined intervals around the lens 60 of the projection optical system PL, and the substrate P is moved in the scanning direction (+ X direction, -X direction). The liquid 50 can flow in the same direction as the direction of movement of the substrate P in parallel with the direction of movement of the substrate P even when the liquid 50 moves in a direction other than the above.

  FIG. 4 is a schematic plan view of the Z stage 51 as viewed from above. A movable mirror 54 is disposed on two mutually perpendicular sides of the rectangular Z stage 51, and a substrate P is held at a substantially center of the Z stage 51 via a holder (not shown). A plurality of shot areas S1 to S20 are set on the substrate P. An auxiliary plate 41 having a plane substantially at the same height as the surface of the substrate P is provided around the substrate P. Although there is a gap of about 1 to 2 mm between the edge of the substrate P and the auxiliary plate 41, the liquid 50 hardly flows into the gap due to the surface tension of the liquid 50. Can also hold the liquid 50 under the projection optical system PL.

  At one corner of the Z stage 51, a reference plate (reference member) 42 is provided integrally with the auxiliary plate 41. On the reference plate 42, a reference mark PFM detected by the substrate alignment system 18 and a substrate mark MFM detected by the mask alignment system 19 are provided in a predetermined positional relationship. The surface of the reference plate 42 is substantially flat, and also serves as a reference surface of the focus / leveling detection system 14. The reference surface of the focus / leveling detection system 14 may be provided on the Z stage 51 separately from the reference plate 42. Further, the reference plate 42 may be provided at a distance of about 1 to 2 mm from the auxiliary plate 41. Further, the reference mark PFM and the reference mark MFM may be provided on different members. Further, the surface of the reference plate 42 is set at substantially the same height as the surface of the substrate P and the surface of the auxiliary plate 41, and the liquid under the projection optical system PL is held while the liquid 50 is held under the projection optical system PL. The immersion part can be moved between the reference plate 42 and the substrate P.

  Next, a procedure for exposing the pattern of the mask M on the substrate P using the above-described exposure apparatus EX will be described with reference to the flowchart of FIG.

[Detection of alignment mark (XY direction) in dry condition]
Before the supply of the liquid 50 from the liquid supply device 1, a measurement process is first performed with no liquid on the substrate P. The control device CONT moves the XY stage 52 while monitoring the output of the laser interferometer 55 so that the optical axis AX of the projection optical system PL advances along the shot areas S1 to S20 along the wavy arrow 43 in FIG. During the movement, the substrate alignment system 18 detects a plurality of alignment marks (not shown) formed on the substrate P without using a liquid (S1). When the substrate alignment system 18 detects an alignment mark, the XY stage 52 is stopped. As a result, the position information of each alignment mark in the coordinate system defined by the laser interferometer 55 is measured. The detection of the alignment marks by the substrate alignment system 18 may be performed by detecting all the alignment marks on the substrate P or only a part thereof. When the substrate alignment system 18 can detect an alignment mark on the substrate P while moving the substrate P, the XY stage 52 need not be stopped.

[Detection of substrate surface position (Z direction) in dry condition]
Also, while the XY stage 52 is moving, the surface information of the substrate P is detected by the focus / leveling detection system 14 without passing through the liquid (S2). Detection of surface information by the focus / leveling detection system 14 is performed for each of all the shot areas S1 to S20 on the substrate P, and the detection result is obtained by associating the position of the substrate P in the scanning direction (X-axis direction) with the control device CONT. Is stored in The detection of the surface information by the focus / leveling detection system 14 may be performed only for a part of the shot areas.
The movement of the XY stage 52 is not limited to that shown in FIG. 4, and may be moved so that a desired detection operation can be performed at a distance as short as possible.
Alternatively, one of the detection of the position information of the plurality of alignment marks and the detection of the surface information of the substrate P may be completed first, and then the other may be detected.

[Detection of reference mark PFM (XY direction) in dry condition]
When the detection of the alignment mark of the substrate P and the detection of the surface information of the substrate P are completed, the control device CONT moves the XY stage 52 so that the detection region of the substrate alignment system 18 is positioned on the reference plate 42. The substrate alignment system 18 detects the reference mark PFM on the reference plate 42 and measures the position information of the reference mark PFM in the coordinate system defined by the laser interferometer 55 (S3).

  Upon completion of the detection processing of the reference mark PFM, the positional relationship between the reference mark PFM and a plurality of alignment marks on the substrate P is obtained. Since the positional relationship between the plurality of alignment marks and the shot areas S1 to S20 is known, when the positional relationship between the reference mark PFM and the plurality of alignment marks on the substrate P is determined, the plurality of shots on the reference mark PFM and the substrate P are determined. This means that the positional relationship with the regions S1 to S20 has been obtained. Since the reference mark PFM and the reference mark MFM have a predetermined positional relationship, the positional relationship between the reference mark MFM and the plurality of shot areas S1 to S20 on the substrate P in the XY plane is determined. .

[Detection of surface position (Z direction) of reference plate in dry condition]
Before or after the detection of the reference mark PFM by the substrate alignment system 18, the control device CONT detects the surface information of the surface (reference surface) of the reference plate 42 by the focus / leveling detection system 14 (S4). Completion of the process of detecting the surface of the reference plate 42 indicates that the relationship between the surface of the reference plate 42 and the surface of the substrate P has been obtained.

[Detection of reference mark MFM in wet condition (detection in X and Y directions)]
Next, the control device CONT moves the XY stage 52 so that the mask alignment system 19 can detect the reference mark MFM on the reference plate 42. Naturally, in this state, the distal end portion 60A of the projection optical system PL and the reference plate 42 face each other. Here, the control device CONT starts supply and recovery of the liquid 50 by the liquid supply device 1 and the liquid recovery device 2, and fills the space between the projection optical system PL and the reference plate 42 with the liquid 50 (S5).

  Next, the control device CONT detects the reference mark MFM via the mask M, the projection optical system PL, and the liquid 50 by the mask alignment system 19 (S6). That is, the positional relationship between the mark on the mask M and the reference mark MFM is detected via the projection optical system PL and the liquid. This means that the position of the mask M in the XY plane, that is, the projection position information of the image of the pattern of the mask M is detected using the reference mark MFM via the projection optical system PL and the liquid 50.

[Detection of reference plate (Z direction) in wet condition]
Further, the control device CONT detects the surface (reference plane) of the reference plate 42 with the focus / leveling detection system 14 in a state where the liquid 50 is supplied between the projection optical system PL and the reference plate 42, and the projection optical system The relationship between the image plane formed via the PL and the liquid 50 and the surface of the reference plate 42 is measured (S7). The focus / leveling detection system 14 can detect the positional relationship (deviation) between the image plane formed by the projection optical system PL via the liquid 50 and the test surface in the wet condition. By detecting the surface of the reference plate 42, the relationship between the image plane formed via the projection optical system PL and the liquid 50 and the surface of the substrate P is detected using the reference plate 42.

[Alignment and exposure in wet conditions]
When the above-described measurement processing is completed, the control device CONT moves the XY stage 52 while supplying and recovering the liquid 50 to expose each of the shot areas S1 to S20 on the substrate P, and moves the XY stage 52 to expose the projection optical system PL. Is moved onto the substrate P. Since the surfaces of the reference plate 42, the auxiliary plate 41, and the substrate P are substantially the same height, the XY stage 52 can be moved while holding the liquid 50 below the projection optical system PL.

  Then, the respective shot areas S1 to S20 on the substrate P are scanned and exposed using the respective information obtained during the above-described measurement processing (S8). That is, during the scanning exposure for each of the shot areas, information on the positional relationship between the reference mark PFM obtained before the supply of the liquid 50 and each of the shot areas S1 to S20 and the reference mark MFM after the supply of the liquid 50 are used. The position of each of the shot areas S1 to S20 on the substrate P and the mask M is adjusted based on the obtained projection position information of the image of the pattern of the mask M (S8).

  During the scanning exposure for each of the shot areas S1 to S20, information on the relationship between the surface of the reference plate 42 and the surface of the substrate P obtained before the supply of the liquid 50, and the surface of the reference plate 42 and the liquid obtained after the supply of the liquid 50 The positional relationship between the surface of the substrate P and the image surface formed via the liquid 50 can be determined without using the focus / leveling detection system 14 based on the information on the positional relationship between the substrate P and the image surface formed via the liquid 50. Adjusted. As described above, the detection of the focus / leveling detection system 14 performed through the liquid 50 is performed only when the surface of the reference plate 42 is detected before the start of exposure of the substrate P. It is possible to perform the detection operation of the focus / leveling detection system 14 with the minimum.

  The surface information of the surface of the substrate P may be detected using the focus / leveling detection system 14 during the scanning exposure, and may be used to confirm the adjustment result of the positional relationship between the surface of the substrate P and the image plane. Further, during the scanning exposure, the surface information of the surface of the substrate P is detected by using the focus / leveling detection system 14, and the position of the surface of the substrate P and the image plane is further taken into account, taking into account the surface information detected during the scanning exposure. The relationship may be adjusted.

  In the above-described embodiment, when the surface information of the substrate P is detected without the liquid, the focus / leveling detection system 14 that projects the detection light into or near the projection area where the image of the pattern of the mask M is formed. However, a focus / leveling detection system (not shown) mounted on the substrate alignment system 18 may be used. The focus / leveling detection system mounted on the substrate alignment system 18 is used to adjust the surface position of the substrate P when the substrate alignment system 18 detects an alignment mark on the substrate P. A specific configuration of the focus / leveling detection system is disclosed in, for example, JP-A-2001-257157 (US Patent Publication 2001 / 0023918A).

In the above-described embodiment, the adjustment of the positional relationship between the surface of the substrate P and the image plane is performed by moving the Z stage 51 holding the substrate P. However, the adjustment of the positional relationship between the mask M and the projection optical system PL is performed. The image plane may be adjusted to the surface of the substrate P by moving a part of the lens, or the wavelength of the exposure light EL may be finely adjusted.
Further, in the above-described embodiment, the supply of the liquid 50 from the liquid supply device 1 is started after the detection of the alignment mark and the reference mark PFM on the substrate P. The liquid 50 is supplied from the liquid supply device 1, and the alignment mark and the reference mark PFM on the substrate P are detected without the liquid while the liquid 50 is locally held on the image plane side of the projection optical system PL. You may do so.
In the above embodiment, the surface information of the substrate P measured in the dry condition is associated with the image plane formed via the projection optical system PL and the liquid 50 via the reference plate 42. However, in a dry condition and a wet condition, the focus / leveling detection system 14 detects the predetermined region on the basis of a predetermined region on the substrate P instead of the reference plate 42, and the substrate measured in the dry condition. The surface information of P and the image plane formed via the projection optical system PL and the liquid 50 may be associated with each other.
In the above embodiment, the focus / leveling detection system 14 is used in both the dry condition and the wet condition. However, the focus / leveling detection system for the dry condition and the focus / leveling detection for the wet condition are used. The system may be provided separately.
When the relationship (offset) between the surface information of the substrate P detected in the dry condition by the focus / leveling detection system 14 and the image plane formed via the liquid by the projection optical system PL is known in advance, The detection in the wet condition by the focus / leveling detection system 14 is omitted, and the image plane and the surface of the substrate P formed by the projection optical system PL via the liquid based on the surface information of the substrate P measured in the dry condition. Each shot area on the substrate P may be subjected to liquid immersion exposure while adjusting the positional relationship between the shot areas. In this case, the reference plate 42 as the reference surface need not be provided on the substrate stage PST. A reference member on which a reference mark is formed is necessary.

  As described above, after the detection of the alignment mark on the substrate P and the detection of the surface information of the substrate P without the intervention of the liquid 50 for immersion exposure, the immersion exposure is performed based on the information. The alignment between the shot areas S1 to S20 on the mask P and the mask M and the adjustment of the positional relationship between the surface of the substrate P and the image plane formed via the liquid 50 can be accurately performed.

  FIG. 5 is a view showing a modification of the present invention, and is a view showing a schematic configuration near the lens 60 of the projection optical system PL. In FIG. 5, for simplicity, the liquid supply device 1, the liquid recovery device 2, the substrate alignment system 18 and the like are omitted.

  The exposure apparatus EX shown in FIG. 5 has a focus / leveling detection system for detecting surface information on the surface of the substrate P on both sides of the lens 60 of the projection optical system PL in the X-axis direction with the same configuration as the focus / leveling detection system 14. 61 and 62 are provided. Each of the detection areas of the focus / leveling systems 61 and 62 can be used even when the liquid 50 is supplied below the projection optical system PL (the liquid 50 is locally held on the image plane side of the projection optical system PL). It is set at a position away from the liquid immersion part. The focus / leveling detection system 61 is used when scanning exposure is performed while the substrate P moves in the −X direction, and the focus / leveling detection system 62 is used when scanning exposure is performed while the substrate P moves in the + X direction. Used.

  In the case of the exposure apparatus of this embodiment, the alignment between the mask M and each shot area on the substrate P is performed in the same manner as in the above-described embodiment.

  In the measurement processing of the present embodiment, the surface position of the reference plate 42 is detected by the focus / leveling detection system 14 while the liquid 50 is supplied between the projection optical system PL and the reference plate 42, and the detection result is The Z-stage 51 is moved based on this, and the surface of the reference plate 42 is adjusted to the image plane formed via the projection optical system PL and the liquid 50. At this time, the respective detection areas of the focus / leveling detection systems 61 and 62 are also located on the reference plate 42 (at this time, no liquid exists in the detection areas of the focus / leveling detection systems 61 and 62), and the focus / leveling is performed. By detecting the surface of the reference plate 42 by the detection systems 61 and 62, the control device CONT controls the image plane formed via the projection optical system PL and the liquid 50 and the liquid by the focus / leveling detection systems 61 and 62. , The relationship with each piece of surface information detected can be obtained.

  When the measurement processing as described above is completed, the control device CONT moves the XY stage 52 while supplying and collecting the liquid 50 to expose each of the shot areas S1 to S20 on the substrate P. The liquid immersion part below the system PL is moved onto the substrate P. Then, the control device CONT scans and exposes each of the shot areas S1 to S20 on the substrate P by using the respective information obtained during the above-described measurement processing. During scanning exposure of each shot area on the substrate P, adjustment of the positional relationship between the image plane formed via the projection optical system PL and the liquid 50 and the surface of the substrate P can be performed without using the focus / leveling detection system 14. This is performed by using focus / leveling detection systems 61 and 62 having a detection area outside the liquid immersion part between the projection optical system PL and the substrate P. For example, when scanning and exposing a certain shot area on the substrate P while moving the substrate P in the −X direction, the shot area to be exposed enters the liquid immersion portion between the projection optical system PL and the substrate P. Previously, the surface level information of the surface of the shot area is sequentially detected by the focus / leveling detection system 61. When the shot area passes through the liquid immersion part between the projection optical system PL and the substrate P, the focus / leveling detection is performed. Based on the surface position information detected by the system 61, the positional relationship between the shot area surface and the image plane is adjusted. Since the relationship between the surface information detected by the focus / leveling detection system 61 and the optimum image plane is obtained in advance by using the reference plate 42, the liquid level can be obtained only by the surface position information detected by the focus / leveling detection system 61. The surface of the shot area can be accurately adjusted to the optimum image plane without being affected by a temperature change of 50 or the like. It is needless to say that the focus / leveling detection system 14 may be used during exposure, as described in the above embodiment.

  In recent years, a twin-stage type exposure apparatus equipped with two stages for holding the substrate P has appeared, but the present invention is also applicable to a twin-stage type exposure apparatus.

  FIG. 6 is a schematic configuration diagram of a twin-stage type exposure apparatus. The twin-stage type exposure apparatus includes first and second substrate stages PST1 and PST2 which can be independently moved on a common base 71. The first and second substrate stages PST1 and PST2 include reference plates 74 and 75 having the same configuration as the reference plate 42 shown in FIG. The twin-stage type exposure apparatus has an exposure station and a measurement / exchange station. The exposure station is equipped with all the systems shown in FIG. 4 (including the focus / leveling detection system 14) except for the substrate alignment system 18. Have been. Further, the measurement / exchange station is equipped with a focus / leveling detection system 73 having a substrate alignment system 72, a projection system 73A, and a light receiving system 73B.

  As a basic operation of such a twin-stage type exposure apparatus, for example, during the exposure processing of the substrate P on the second substrate stage PST2 at the exposure station, the substrate P on the first substrate stage PST1 is exposed at the measurement / exchange station. Exchange and measurement processing are performed. When the respective operations are completed, the second substrate stage PST2 moves to the measurement / exchange station, and in parallel with this, the first substrate stage PST1 moves to the exposure station. This time, measurement and exchange are performed at the second substrate stage PST2. The processing is performed, and the exposure processing is performed on the substrate P on the first substrate stage PST1.

  When the present invention is applied to a twin-stage type exposure apparatus, the measurement processing performed without using the liquid described in the above-described embodiment is performed in the measurement / exchange station. For example, while the liquid immersion exposure processing is being performed on the substrate P on the second substrate stage PST2 in the exposure station, the substrate alignment system 72 and the focus / Using the leveling detection system 73 and the reference plate 74, a measurement process that does not involve a liquid is performed. When the measurement process without the liquid is completed, the first substrate stage PST1 and the second substrate stage PST2 are exchanged. As shown in FIG. 6, the reference plate 74 of the first substrate stage PST1 and the projection optical First substrate stage PST1 is positioned such that system PL faces. In this state, the control device CONT starts supplying the liquid 50, fills the space between the projection optical system PL and the reference plate 74 with the liquid 50, and performs the same measurement processing and exposure processing via the liquid as in the above-described embodiment. I do. The alignment information of each shot area once obtained at the measurement / exchange station is defined (stored) with reference to the reference mark PFM of the reference plate, and is used when the immersion exposure is performed at the exposure station. Moves the first substrate stage PST1 such that each shot area is positioned based on the positional relationship between the reference mark MFM and the mask M formed in a predetermined positional relationship with respect to the reference mark PFM of the reference plate. Is controlled. That is, the alignment information of each shot area obtained at the measurement / exchange station is effectively transferred to the exposure station using the reference marks PFM and MFM.

As described above, in the case of the twin-stage type exposure apparatus, it is possible to perform the measurement process without using the liquid on the other stage during the liquid immersion exposure process on the other stage, thereby improving the throughput of the exposure process. Can be. The structure and exposure operation of a twin-stage type exposure apparatus are described in, for example, JP-A-10-163099 and JP-A-10-214783 (corresponding to U.S. Pat. Nos. 6,341,007, 6,400,441, 6,549, 269 and 6,590,634), JP-T-2000-505958 (corresponding US Pat. No. 5,969,441) or US Pat. No. 6,208,407.
In the above-described twin-stage type exposure apparatus, the focus / leveling detection system 14 is disposed at the exposure station. However, as disclosed in US Pat. No. 6,208,407, the focus / leveling of the exposure station is performed. The detection system may be omitted, and the positional relationship between the image plane of the projection optical system PL and the surface of the substrate P may be adjusted by using an interferometer that measures positional information of the substrate stage PST in the Z direction. Of course, an interferometer that measures the position information of the substrate stage PST in the Z direction and the focus / leveling detection system 14 may be used in combination.

  Further, in the above embodiment, the reference mark MFM of the reference plate (for example, the reference plate 42) is detected by the mask alignment system 19 via the liquid 50, but the transparent member having a predetermined thickness is provided on the reference mark MFM. (Cover glass, correction member) may be arranged, and the detection of the reference mark MFM by the mask alignment system 19 may be performed without using a liquid. In this case, a pseudo liquid immersion state is formed between the projection optical system PL and the reference mark MFM by the transparent member, so that the image of the pattern of the mask M is projected using the reference mark MFM without using a liquid. Position information can be accurately measured. Therefore, not only the alignment mark on the substrate P but also the reference mark MFM is detected without passing through the liquid 50, so that it is necessary to stably and accurately obtain the alignment information for aligning the mask M and the substrate P. Can be.

  Further, the mask alignment system 19 is not limited to the configuration disclosed in Japanese Patent Application Laid-Open No. 7-176468, and the point is that the position of the mask M (the mark of the mask M) and the reference (MFM) on the substrate stage PST It suffices if the relationship can be detected.

  In the above-described embodiment, the liquid is supplied onto the substrate P after the alignment mark on the substrate P is detected without the liquid. Even if the stage PST is deformed and the liquid immersion exposure is performed based on the position information of the alignment mark detected in the dry condition and the surface information of the substrate P, an error such as a displacement or defocus occurs, and The pattern image of M may not be projected on the substrate P in a desired state.

  In such a case, the alignment (alignment) between the pattern image and each shot on the substrate P is, for example, a method disclosed in Japanese Patent Application Laid-Open No. 2002-353121 (US Patent Publication 2002 / 0042664A). Correction information (map information) for correcting misalignment caused by supplying the liquid onto the substrate P using a method such as the above is prepared in advance, and the position information of the alignment mark of the substrate P detected in the dry condition is prepared. In addition, the position of the pattern image and each shot area on the substrate P may be adjusted in consideration of the correction information. Alternatively, test exposure may be performed to obtain similar correction information from the positional shift amount of the pattern of each shot, and the position of the substrate P and each shot area may be aligned using the correction information.

  Regarding the focus / leveling control, correction information for correcting an error (such as defocus) caused by supplying liquid onto the substrate P by performing test exposure or the like is obtained in advance, and is detected in a dry condition. What is necessary is just to adjust the positional relationship between the image plane formed via the liquid by the projection optical system PL and the surface of the substrate P by adding the correction information to the surface information of the substrate P.

  As described above, pure water is used as the liquid 50 in the present embodiment. Pure water has the advantage that it can be easily obtained in large quantities at a semiconductor manufacturing plant or the like, and that there is no adverse effect on the photoresist on the substrate P, optical elements (lenses), and the like. In addition, since pure water has no adverse effect on the environment and has a very low impurity content, an effect of cleaning the surface of the substrate P and the surface of the optical element provided on the tip end surface of the projection optical system PL can be expected. .

  The refractive index n of pure water (water) with respect to the exposure light EL having a wavelength of about 193 nm is said to be approximately 1.44 to 1.47, and an ArF excimer laser light (wavelength of 193 nm) is used as a light source of the exposure light EL. Is used, the wavelength is shortened to 1 / n on the substrate P, that is, about 131 to 134 nm, and a high resolution is obtained. Further, since the depth of focus is expanded to about n times, that is, about 1.44 to 1.47 times as much as that in the air, if it is sufficient to secure the same depth of focus as when using it in the air, In addition, the numerical aperture of the projection optical system PL can be further increased, and the resolution is also improved in this regard.

  In the above embodiment, the lens 60 is attached to the tip of the projection optical system PL. However, as an optical element attached to the tip of the projection optical system PL, the optical characteristics of the projection optical system PL, such as aberration (spherical aberration, coma) Etc.) may be used. Alternatively, a parallel plane plate that can transmit the exposure light EL may be used. By making the optical element that comes into contact with the liquid 50 a parallel plane plate that is less expensive than a lens, the transmittance of the projection optical system PL and the exposure light EL on the substrate P during transportation, assembly, adjustment, and the like of the exposure apparatus EX. Even if a substance (for example, a silicon-based organic substance) that reduces the illuminance and the uniformity of the illuminance distribution adheres to the parallel flat plate, it is sufficient to replace the parallel flat plate just before supplying the liquid 50. There is an advantage that the replacement cost is reduced as compared with the case where the optical element that comes into contact with the lens is a lens. That is, the surface of the optical element that comes into contact with the liquid 50 due to scattering particles generated from the resist due to the irradiation of the exposure light EL or the adhesion of impurities in the liquid 50 is stained. Although it is necessary to use this optical element as an inexpensive parallel flat plate, the cost of replacement parts can be reduced and the time required for replacement can be reduced as compared with a lens, and the maintenance cost (running cost) increases. And a decrease in throughput can be suppressed.

  When the pressure between the optical element at the tip of the projection optical system PL and the substrate P caused by the flow of the liquid 50 is large, the optical element is not replaced but the optical element is moved by the pressure. It may be fixed firmly so that it does not occur.

The liquid 50 in the above embodiment is water, but may be a liquid other than water. For example, when the light source of the exposure light EL is an F ₂ laser, the F ₂ laser light does not transmit water. in this case, it may be a F ₂ laser, for example, fluorine-based which can transmit a light oil (liquid) or perfluoropolyether (PFPE) as fluid 50. In addition, as the liquid 50, a liquid that has transparency to the exposure light EL, has a refractive index as high as possible, and is stable with respect to the photoresist applied to the projection optical system PL and the surface of the substrate P (for example, Cedar) Oil) can also be used.

  The substrate P in each of the above embodiments is not limited to a semiconductor wafer for manufacturing a semiconductor device, but also a glass substrate for a display device, a ceramic wafer for a thin-film magnetic head, or an original mask or reticle used in an exposure apparatus. (Synthetic quartz, silicon wafer) and the like are applied.

  Further, in the above-described embodiment, the exposure device that locally fills the space between the projection optical system PL and the substrate P with the liquid is employed, but the stage holding the substrate to be exposed is moved in the liquid tank. The present invention can also be applied to an immersion exposure apparatus for forming a liquid tank having a predetermined depth on a stage and holding a substrate therein. The structure and exposure operation of an immersion exposure apparatus for moving a stage holding a substrate to be exposed in a liquid tank are disclosed in detail, for example, in JP-A-6-124873. The structure and exposure operation of a liquid immersion exposure apparatus that forms a liquid tank and holds a substrate therein is disclosed in detail in, for example, JP-A-10-303114 (US Pat. No. 5,825,043). I have.

  The exposure apparatus EX includes a step-and-scan type scanning exposure apparatus (scanning stepper) that scans and exposes the pattern of the mask M by synchronously moving the mask M and the substrate P. Can be applied to a step-and-repeat type projection exposure apparatus (stepper) in which the pattern of the mask M is exposed collectively while the substrate is stationary, and the substrate P is sequentially moved stepwise. The present invention is also applicable to a step-and-stitch type exposure apparatus that transfers at least two patterns on the substrate P while partially overlapping each other.

  The type of the exposure apparatus EX is not limited to an exposure apparatus for manufacturing a semiconductor element for exposing a semiconductor element pattern onto the substrate P, but may be an exposure apparatus for manufacturing a liquid crystal display element or a display, a thin film magnetic head, an imaging element (CCD). ) Or an exposure apparatus for manufacturing a reticle or a mask.

  When a linear motor is used for the substrate stage PST or the mask stage MST, any of an air levitation type using an air bearing and a magnetic levitation type using Lorentz force or reactance force may be used. Each of the stages PST and MST may be of a type that moves along a guide, or may be a guideless type that does not have a guide. Examples using a linear motor for the stage are disclosed in U.S. Patents 5,623,853 and 5,528,118.

  As a driving mechanism of each stage PST, MST, a planar motor that drives each stage PST, MST by electromagnetic force by facing a magnet unit having a two-dimensionally arranged magnet and an armature unit having a two-dimensionally arranged coil. May be used. In this case, one of the magnet unit and the armature unit may be connected to the stages PST and MST, and the other of the magnet unit and the armature unit may be provided on the moving surface side of the stages PST and MST.

  The reaction force generated by the movement of the substrate stage PST may be mechanically released to the floor (ground) using a frame member so as not to be transmitted to the projection optical system PL. The method of processing this reaction force is disclosed in detail, for example, in Japanese Patent Application Laid-Open No. 8-166475 (US Pat. No. 5,528,118).

  The reaction force generated by the movement of the mask stage MST may be mechanically released to the floor (ground) using a frame member so as not to be transmitted to the projection optical system PL. The method of processing this reaction force is disclosed in detail, for example, in Japanese Patent Application Laid-Open No. 8-330224 (US Pat. No. 5,874,820).

  As described above, the exposure apparatus EX according to the embodiment of the present invention controls various subsystems including the respective components described in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. Manufactured by assembling. Before and after this assembly, adjustments to achieve optical accuracy for various optical systems, adjustments to achieve mechanical accuracy for various mechanical systems, and various electric systems to ensure these various accuracy Are adjusted to achieve electrical accuracy. The process of assembling the exposure apparatus from the various subsystems includes mechanical connection, wiring connection of an electric circuit, and piping connection of a pneumatic circuit among the various subsystems. It goes without saying that there is an assembling process for each subsystem before the assembling process from these various subsystems to the exposure apparatus. When the process of assembling the various subsystems into the exposure apparatus is completed, comprehensive adjustment is performed, and various precisions of the entire exposure apparatus are secured. It is desirable that the exposure apparatus be manufactured in a clean room in which the temperature, the degree of cleanliness, and the like are controlled.

  As shown in FIG. 7, for a microdevice such as a semiconductor device, a step 201 for designing the function and performance of the microdevice, a step 202 for manufacturing a mask (reticle) based on the design step, a substrate which is a base material of the device, as shown in FIG. 203, an exposure processing step 204 of exposing a mask pattern to a substrate by the exposure apparatus EX of the above-described embodiment, a device assembling step (including a dicing step, a bonding step, and a packaging step) 205, an inspection step 206, and the like. Manufactured through

FIG. 1 is a schematic configuration diagram illustrating an embodiment of an exposure apparatus of the present invention. FIG. 3 is a diagram illustrating a positional relationship between a distal end portion of a projection optical system and a liquid supply device and a liquid recovery device. It is a figure showing an example of arrangement of a supply nozzle and a recovery nozzle. FIG. 3 is a plan view of a substrate stage that holds a substrate. FIG. 6 is a schematic configuration diagram illustrating another embodiment of the exposure apparatus of the present invention. FIG. 6 is a schematic configuration diagram illustrating another embodiment of the exposure apparatus of the present invention. It is a flowchart figure which shows an example of the manufacturing process of a semiconductor device. 5 is a flowchart showing a procedure for exposing a mask pattern on a substrate using an exposure apparatus.

Explanation of reference numerals

1. Liquid supply device 2. Liquid recovery device
14. Focus / leveling detection system (surface detection system)
18 ... substrate alignment system (first alignment system)
19: mask alignment system (second alignment system),
42: Reference member, 50: Liquid, CONT: Control device, EX: Exposure device, P: Substrate,
PL: projection optical system, PST: substrate stage (first substrate stage),
PST1: first substrate stage, PST2: second substrate stage

Claims (32)

An exposure apparatus for exposing a substrate by transferring an image of a pattern onto a substrate via a liquid,
A projection optical system for projecting an image of the pattern onto the substrate,
A first substrate stage for holding the substrate,
A liquid supply device for supplying the liquid to the image plane side of the projection optical system,
A surface detection system that detects surface information of the substrate surface without passing through a liquid,
An exposure apparatus that performs liquid immersion exposure on the substrate while adjusting a positional relationship between the substrate surface and an image surface formed via the liquid by the projection optical system based on the detected surface information.   A reference member having a reference surface of the surface detection system and provided on the first substrate stage, using the reference surface, surface information of the substrate surface detected without passing through the liquid, The exposure apparatus according to claim 1, wherein a relationship with an image plane formed via the liquid is determined by a projection optical system.   3. The exposure apparatus according to claim 2, wherein the surface detection system detects a relationship between the substrate surface and the reference surface as the surface information.   In a state where the liquid is supplied between the projection optical system and the reference surface, a relationship between an image surface formed by the projection optical system via the liquid and the reference surface is detected, and the image surface and The exposure apparatus according to claim 3, wherein a relationship between the substrate surface and the image surface is determined based on a relationship with the reference surface.   The relationship between the image plane and the reference plane, which is detected in a state in which liquid is supplied between the projection optical system and the reference plane, is determined using another surface detection system different from the surface detection system. The exposure apparatus according to claim 4, wherein the exposure is performed.   The liquid supply device according to claim 2, wherein after the surface detection system detects surface information of the substrate surface, the liquid supply device starts supplying the liquid in a state where the projection optical system and the reference surface are opposed to each other. The exposure apparatus according to claim 1.   The detection of the surface information of the substrate surface performed by the surface detection system without using a liquid is performed in a state where the liquid is held on the image plane side of the projection optical system. Exposure apparatus according to the above.   A second substrate stage different from the first substrate stage, wherein the surface detection system detects surface information on the surface of the substrate held on the first substrate stage, and the substrate held on the second substrate stage; The exposure apparatus according to any one of claims 1 to 7, wherein the substrate held on the second substrate stage is subjected to immersion exposure while a liquid is supplied between the projection optical system and the projection optical system.   A first alignment system that detects an alignment mark on the substrate held by the first substrate stage without using a liquid; and aligns the substrate with the pattern based on a detection result of the first alignment system. 9. The exposure apparatus according to claim 8, wherein the substrate is subjected to liquid immersion exposure while performing the step.   Further, a control device for controlling the operation of the exposure apparatus, the control device, based on the detected surface information, the substrate surface and the projection optical system and the image surface formed via the liquid and The exposure apparatus according to claim 1, wherein the positional relationship is adjusted. An alignment system for detecting the alignment mark on the substrate without using a liquid,
The exposure apparatus according to any one of claims 1 to 7, wherein the substrate is subjected to immersion exposure while performing alignment between the substrate and the pattern based on a detection result of the alignment system. The surface of the reference member is substantially flush with the surface of the substrate held on the first substrate stage,
The first substrate stage holds the liquid locally on the image plane side of the projection optical system, while the projection optical system and the reference member face each other from the state where the projection optical system and the reference member face each other. The exposure apparatus according to any one of claims 2 to 11, wherein the exposure apparatus is movable to a state in which the elements are opposed to each other. The liquid is locally held on the image plane side of the projection optical system,
13. The exposure apparatus according to claim 1, wherein the first substrate stage has a flat portion substantially flush with a surface of the substrate held around the substrate held by the first substrate stage. An exposure apparatus that exposes a plurality of shot areas on the substrate by sequentially exposing a pattern image to a plurality of shot areas on the substrate via a liquid,
A projection optical system for projecting an image of the pattern onto the substrate,
A first substrate stage for holding the substrate,
A liquid supply device for supplying the liquid to the image plane side of the projection optical system,
A first alignment system that detects the alignment mark on the substrate without the intervention of a liquid,
An exposure apparatus that performs liquid immersion exposure on the substrate while performing alignment between the substrate and the pattern based on a detection result of the first alignment system.   A reference member provided on the first substrate stage and having a reference mark formed thereon, the detection result of the first alignment system being formed using the reference mark, and being formed by the projection optical system via the liquid 15. The exposure apparatus according to claim 14, wherein a relationship with a projection position of the image of the pattern is determined.   The exposure apparatus according to claim 15, wherein the first alignment system determines a positional relationship between the reference mark and each shot area on the substrate by detecting the alignment mark.   A second alignment system that detects the fiducial mark through the projection optical system, and based on a detection result of the second alignment system, each shot area on the substrate and the projection optical system through the liquid. 17. The exposure apparatus according to claim 16, wherein a relationship with a projection position of an image of the pattern to be formed is determined.   18. The exposure apparatus according to claim 17, wherein the second alignment system detects the reference mark in a state where a liquid is supplied between the projection optical system and the reference member.   A second alignment system for detecting a positional relationship between the reference mark and the pattern via the projection optical system, wherein each of the shot areas on the substrate and the projection optical system are detected based on a detection result of the second alignment system. 16. The exposure apparatus according to claim 15, wherein a relationship between the pattern and a projection position of an image of the pattern formed through the liquid is determined by a system.   The pattern is formed on a mask, and the second alignment system detects the positional relationship between the reference mark and the mark of the mask in a state where liquid is supplied between the projection optical system and the reference member. The exposure apparatus according to claim 19, wherein the exposure is performed.   The exposure apparatus according to claim 17, wherein the second alignment system detects the reference mark via a transparent member disposed between the projection optical system and the reference member, and the projection optical system.   15. The liquid supply device according to claim 14, wherein after the first alignment system detects an alignment mark on the substrate, the liquid supply device starts supplying the liquid in a state where the projection optical system and the reference member face each other. Exposure apparatus according to the above. The surface of the reference member is substantially flush with the surface of the substrate held on the first substrate stage,
The first substrate stage is configured such that the projection optical system and the substrate face each other from a state where the projection optical system and the reference member face each other while holding the liquid on the image plane side of the projection optical system. The exposure apparatus according to any one of claims 15 to 22, wherein the exposure apparatus can be moved to a state where the exposure apparatus is in a state where the exposure apparatus is in an open state. The liquid is locally held on the image plane side of the projection optical system,
24. The exposure apparatus according to claim 14, wherein the first substrate stage has a flat portion substantially flush with a surface of the substrate held around the substrate held by the first substrate stage.   A second substrate stage different from the first substrate stage, wherein the first alignment system detects an alignment mark on the substrate held by the first substrate stage, and the substrate held by the second substrate stage. The exposure apparatus according to any one of claims 14 to 24, wherein the substrate held on the second substrate stage is subjected to immersion exposure while a liquid is supplied between the substrate and the projection optical system.   A control device for controlling the operation of the exposure apparatus, wherein the control device supplies the liquid to the substrate based on a detection result of the first alignment system in a state where the liquid is not supplied to the substrate. 26. The exposure apparatus according to claim 14, wherein a substrate stage is controlled so as to perform alignment between the substrate and the pattern in a state where the exposure is performed.   A device manufacturing method using the exposure apparatus according to claim 1. A liquid immersion exposure method for exposing a substrate by transferring an image of a pattern onto a substrate via a liquid,
Obtaining surface information of the substrate surface by measurement without passing through the liquid supplied on the substrate,
Supplying a liquid on the substrate;
Performing a liquid immersion exposure of the substrate while adjusting a positional relationship between the substrate surface and an image surface formed via the liquid based on the obtained surface information.   In the step of obtaining the surface information of the substrate surface by measurement not involving the liquid supplied on the substrate, the relationship between the image surface of the pattern formed via the liquid by supplying the liquid on the substrate and the surface information of the substrate surface 29. The immersion exposure method according to claim 28, further comprising:   29. The exposure method according to claim 28, wherein the step of determining the surface position of the substrate surface and the step of immersion exposure are performed in different stations. A liquid immersion exposure method for exposing a substrate by transferring an image of a pattern onto a substrate via a liquid,
Detecting an alignment mark on the substrate when liquid is not supplied on the substrate,
Supplying a liquid on the substrate;
A liquid immersion exposure method comprising the steps of: performing liquid immersion exposure of the substrate while performing alignment between the substrate supplied with liquid and the pattern based on the detection result of the alignment mark. 32. The exposure method according to claim 31, wherein the step of detecting the alignment mark and the step of performing liquid immersion exposure are performed in different stations.

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