Stage apparatus, fixation method, exposure apparatus, exposure method, and device-producing method Number:7,394,526 from the United States Patent and Trademark Office (PTO) owispatent A stage apparatus including: a movement member movable with a plate member placed on a placement surface; and a fixing apparatus that fixes said plate member to said placement surface in parallel with said movement member passing through a prescribed first region.<H producing, apparatus, Stage, apparatus, 7394526.html, Patent, pto, 7394526

Title: Stage apparatus, fixation method, exposure apparatus, exposure method, and device-producing method

Abstract: A stage apparatus including: a movement member movable with a plate member placed on a placement surface; and a fixing apparatus that fixes said plate member to said placement surface in parallel with said movement member passing through a prescribed first region.

Patent Number: 7,394,526 Issued on 07/01/2008 to Shibazaki

Inventors: Shibazaki; Yuichi (Kumagaya, JP)
Assignee: Nikon Corporation (Tokyo, JP)

Appl. No.: 11/290,573

Filed: December 1, 2005

Related U.S. Patent Documents


Application Number	Filing Date	Patent Number	Issue Date
PCT/JP2004/008063	Jun., 2004

Foreign Application Priority Data


Jun 04, 2003 [JP]			2003-159800

Current U.S. Class: 355/72 ; 355/75

Current International Class: G03B 27/58 (20060101); G03B 27/62 (20060101)

Field of Search: 355/53,72-76 310/10,12 318/649 378/34,35

References Cited [Referenced By]

U.S. Patent Documents


4711438	December 1987	Guarino
6172738	January 2001	Korenaga et al.
6281654	August 2001	Lee
6683433	January 2004	Lee
6806943	October 2004	Barringer et al.
6885435	April 2005	Galburt
6888621	May 2005	Araki et al.

Foreign Patent Documents


A 04-220648	Aug., 1992	JP
U 07-011287	Feb., 1995	JP
A 08-166475	Jun., 1996	JP
A 08-330224	Dec., 1996	JP
A 09-148406	Jun., 1997	JP
A 10-149979	Jun., 1998	JP
A 10-189700	Jul., 1998	JP
A 11-040657	Feb., 1999	JP
A 2002-343850	Nov., 2002	JP
A 2004-328014	Nov., 2004	JP

Primary Examiner: Nguyen; Hung Henry
Attorney, Agent or Firm: Oliff & Berridge, PLC

Parent Case Text

CROSS-REFERENCE TO RELATED APPLICATION

This is a Continuation Application of International Application No. PCT/JP2004/008063, filed Jun. 3, 2004, which claims priority to Japanese Patent Application No. 2003-159800, filed Jun. 4, 2003. The contents of the aforementioned applications are incorporated herein by reference.

Claims

What is claimed is:

1. A stage apparatus comprising: a movement member movable with a plate member placed on a placement surface; a fixing apparatus that fixes the plate member to the placement surface in parallel with the movement member passing through a prescribed first region; and a conversion apparatus which converts movement of the movement member to motive force of the fixing apparatus by mechanical contact with a part of the movement member when the movement member passes through the first region.

2. A stage apparatus according to claim 1, wherein the movement member passes through the first region after moving from a second region in which the plate member is placed on the movement member, and the fixing apparatus fixes the plate member to the placement surface in parallel with the movement member from the second region passing through the first region.

3. A stage apparatus according to claim 1, wherein the movement member passes through the first region during movement toward a third region in which the plate member is removed from the movement member, and the fixing apparatus releases the fixing of the plate member in parallel with the movement member from the third region passing through the first region.

4. A stage apparatus according to claim 3, wherein the second region and the third region are the same region.

5. A stage apparatus according to claim 3, wherein a movement direction of the movement member when the fixing apparatus fixes the plate member and a movement direction when the fixing apparatus releases the fixing of the plate member are mutually opposing directions.

6. A stage apparatus according to claim 1, wherein the conversion apparatus is a cam apparatus having a cam follower provided on the fixing apparatus and a cam member provided on a base part that supports the movement member.

7. A stage apparatus according to claim 6, wherein the cam follower has a bearing that reduces friction with the cam member.

8. A stage apparatus according to claim 6, wherein the cam member has a shock-absorber that reduces resistance when contact is made with the cam follower.

9. A stage apparatus according to claim 6, further comprising a pull-back apparatus that causes the cam member to pull back from a movement path of the movement member.

10. A stage apparatus according to claim 2, wherein the conversion apparatus has a cam apparatus, at least part of the cam apparatus being disposed in the second region.

11. A stage apparatus according to claim 1, wherein the fixing apparatus has a holding apparatus that holds the fixing of the plate member.

12. A stage apparatus according to claim 1, wherein the fixing apparatus has a resilient body in a part that makes contact with the plate member.

13. A stage apparatus according to claim 1, further comprising a second movement member provided so as to move in a direction that is opposite from a direction of movement of the movement member in accordance with a weight ratio with the movement member, by a reaction force generated when the movement member is driven, wherein a weight of the movement member includes at least part of a weight of the fixing apparatus.

14. An exposure apparatus comprising a mask stage that holds a mask and a substrate stage that holds a substrate, wherein a pattern formed on the mask is exposed onto the substrate, and wherein a stage apparatus according to claim 1 is used as at least one of the mask stage and the substrate stage.

15. A method for producing a device, which includes a lithography step, wherein an exposure apparatus according to claim 14 is used in the lithography step.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a stage apparatus that moves precisely in one dimension or two dimensions over a flat table onto which is placed a mask or substrate onto which a pattern is described, and to an exposure apparatus or the like using such a stage apparatus.

2. Description of Related Art

In the past, in a microlithography apparatus in which a circuit pattern of a semiconductor device or a liquid-crystal device is formed by shining illumination light (an energy beam such as an ultraviolet beam, an X-ray beam, or an electron beam or the like) onto a mask or the like on which a circuit pattern is described so as to perform exposure of a sensitized substrate (a semiconductor wafer or glass plate or the like onto which a resist layer has been applied) by projection through a projection image forming system that is full-size or that has a reduction or magnification ratio, a stage apparatus is provided, onto which the mask or sensitized substrate is placed, and which moves in one dimension or in two dimensions within a plane (XY plane), under position servocontrol by a laser interferometer.

In such a stage apparatus, the mask or substrate is generally vacuum chucked by a vacuum chucking force. In particular, because the surface area that is held by the vacuum chucking is small and scanning is done at a speed that is approximately 4 or 5 times that of the wafer, there is a tendency for the mask holding force to be insufficient, so that the mask position shifts during the scanning of the mask stage. For this reason, there is a technology, as shown in Japanese Unexamined Patent Application, First Publication No. H10-149979, of pressing a member serving as a positioning reference up against the mask, so as to prevent offset.

In recent years, in order to improve the productivity of exposure apparatuses, there is a desire to increase the speed of the reticle stage apparatus or wafer stage, so that the acceleration to which the wafer is subjected reaches 5 to 6 G.

In the above-described technology, however, because the force that holds the mask is only the vacuum chucking force that acts on the bottom surface of the mask, if the stage apparatus is moved with a high acceleration, there is the problem of insufficient holding force, resulting in mask offset and a deterioration of the transfer precision.

SUMMARY OF THE INVENTION

The present invention was made in consideration of the above-noted situation, and has as object to provide a stage apparatus that, by holding a mask or the like with a strong force, has no danger of position offset, and an exposure apparatus that uses same. To make the description of the present invention easier to understand, the description is presented with reference to reference numerals applied to drawings of embodiments. However, the present invention is not restricted to those embodiments.

A first aspect of the present invention is a stage apparatus includes: a movement member movable with a plate member placed on a placement surface; and a fixing apparatus that fixes the plate member to the placement surface in parallel with the movement member passing through a prescribed first region.

In accordance with an embodiment of the invention, it is possible for the fixing apparatus to be driven so as to fix the plate member automatically by the stage apparatus merely passing through a prescribed region.

In the embodiment of the invention, the movement member can pass through the first region after moving from a second region in which the plate member is placed on the movement member, and the fixing apparatus can fix the plate member to the placement surface in parallel with the movement member from the second region passing through the first region. By doing this, the stage apparatus onto which the plate member is placed on the movement member simply passing through the first region after moving from the second region, so that the fixing apparatus is driven so as to fix the plate member automatically.

In the embodiment of the invention, the movement member can pass through the first region during moving toward a third region in which the plate member is removed from the movement member, and the fixing apparatus can release fixing of the plate member in parallel with the movement member from the third region passing through the first region. By doing this, the stage in which the plate member is placed on the movement member simply moves through the first region and moves to the third region, so that the fixing apparatus is driven so as to release the fixation of the plate member.

Additionally, in the case in which the second region and the third region are one and the same region, the region in which the plate member is placed on the movement member and the region in which the plate member is removed from the movement member are one and the same region, making it possible to suppress an excessive increase in the size of the apparatus.

Also, if the direction of movement when the movement member passes through the first region when the fixing apparatus fixes the plate member and the direction of movement when movement member passes through the first region when the fixing apparatus releases the fixation are mutually inconsistent, it is possible to make a clear distinction between the region in which the plate member is fixed and the region in which the fixing of the plate member is released, surrounding the first region.

Also, if a conversion apparatus that converts the movement of the movement member to motive force of the fixing apparatus by coming into contact with part of the movement member when the movement member passes through the first region, it is possible to cause the driving of the fixing member without using a special actuator.

In the embodiment of the invention, the conversion apparatus can be a cam apparatus having a cam follower provided on the fixing apparatus and a cam member provided on a base part that supports the movement member. By doing this, it is possible by the cam apparatus to convert movement of the stage apparatus to motive force of the fixing apparatus easily and reliably.

Also, if the cam follower is provided with a bearing that reduces the friction with the cam member, it is possible to make the operation of the fixing apparatus smooth, and also to extend the life of the apparatus.

Also, if the cam member is provided with a shock-absorber which reduces the resistance when contact is made with the cam follower, it is possible to make the operation of the fixing apparatus smooth, and also to extend the life of the apparatus.

Also, if a pull-back apparatus that causes the cam follower to pull-back from the movement paths of the movement member, it is possible by causing the cam member to pull-back from the movement path to stop the drive of the fixing apparatus.

In the embodiment of the invention, a cam apparatus can be provided that turns movement of the movement member into motive force of the fixing apparatus by mechanical contact with a part of the movement member when the movement member passes through the first region, at least part of the cam apparatus disposed in the second region. Because the cam apparatus is disposed in the second region, there is no contact between the fixing apparatus and the cam apparatus in other regions, enabling the achievement of precise movement by the stage apparatus.

If the fixing apparatus has a holding apparatus that holds fixing of the plate member, it is possible to hold (maintain) the fixing of the plate member even in the case in which the fixing apparatus and cam apparatus are not in contact.

Also, if the fixing apparatus is provided with a springy body at a part contacting with the plate member, it is possible to avoid damage to the plate member by the fixing apparatus.

In the embodiment of the invention, a second movement member can be provided so as to move in a direction that is opposite from the direction of movement of the movement member in accordance with the weight ratio with the movement member, by the reaction force generated when the movement member is driven, and the weight of the movement member can include at least part of the weight of the fixing apparatus. By doing this, the above-noted repelling force can be cancelled out or relaxed by the movement of the second movement member. For this reason, it is possible to suppress vibration of the stage apparatus. Also, if the above-noted repelling force is cancelled out, it is further possible to prevent a shift in the center of gravity of the stage apparatus.

A second aspect of the present invention is a method of fixing a plate member to the movement member of the stage apparatus, whereby the movement member performs fixing of the plate member so as to pass through a prescribed first region provided within the stage apparatus.

By doing this, by the stage apparatus merely passing through a prescribed region, it is possible to fix the plate member by drive of the fixing apparatus automatically, without providing a special drive apparatus.

Additionally, by passing through the first region after the movement member passes from the second region in which the plate member is placed on the movement member so that the fixing apparatus fixes the plate member, the stage apparatus onto which the plate member is placed on the movement member simply passing through the first region after moving from the second region drives the fixing apparatus so as to fix the plate member automatically.

Also, during the movement of the movement member towards the third region in which the plate member is removed from the movement member it passes through the first region so that the fixing apparatus releases the fixing of the plate member, by the stage apparatus in which the plate member is placed onto the movement member simply moving to the third region after passing through the first region can release the fixing of the plate member automatically by drive of the fixing apparatus.

Additionally, in the case in which the second region and the third region are one and the same region, the region in which the plate member is placed on the movement member and the region in which the plate member is removed from the movement member are one and the same region, making it possible to suppress an excessive increase in the size of the apparatus.

A third aspect of the present invention is an exposure apparatus having a mask stage that holds a mask and a substrate stage that holds a substrate, in which a substrate is exposed with a pattern formed on the mask, wherein a stage apparatus according to the first aspect of the present invention is used for at least one of the mask stage and substrate stage.

By the above, because the fixing apparatus holds the mask or substrate with firm pressure, even if the stage is moved at high speed during exposure, it is possible to transfer a highly precise pattern onto the substrate without shifting of the mask or substrate.

A fourth aspect of the present invention is an exposure method whereby the mask is fixed to a mask stage, the substrate is fixed to a substrate stage, and the substrate is exposed, in which the fixing method according to the second aspect of the present invention is used for at least one of the mask fixing method and the substrate fixing method.

By the above, because the mask or substrate is held by firm pressure, even if the stage is quickly accelerated or decelerated during exposure processing, it is possible to transfer a highly precise pattern onto the substrate without shifting of the mask or substrate.

A fifth aspect of the present invention is method of producing a device that include a lithography process step, in which the exposure apparatus according to the third aspect of the present invention is used in the lithography step. In the method for producing a device that includes a lithography process step, the exposure method according to the fourth aspect of the present invention was used.

By the above, it is possible to produce a device onto which a highly precise pattern is transferred.

According to a stage apparatus of the first aspect of the present invention, it is possible to automatically drive a fixing apparatus by merely the stage apparatus passing through a prescribed region, without providing a special drive apparatus.

According to a fixation method of the second aspect of the present invention, it is possible to automatically drive a fixing apparatus my merely the stage apparatus passes through a prescribed region, without providing a special drive apparatus.

According to an exposure apparatus of the third aspect of the present invention, because a fixing apparatus fixes a mask or substrate by pressure holding, even if the stage is moved at high speed during exposure processing, the mask or substrate does not shift, making it possible to transfer a precise pattern to the mask.

According to an exposure apparatus of the fourth aspect of the present invention, because a mask or substrate is held firmly by pressure holding, even if the stage is moved at high speed during exposure processing, the mask or substrate does not shift, making it possible to transfer a precise pattern to the mask.

According to a method for manufacturing a device of the fifth aspect of the present invention, it is possible to manufacture a device with a highly precise transferred pattern.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an oblique view showing a reticle stage apparatus of a first embodiment.

FIGS. 2A and 2B are oblique views showing a reticle clamp of the first embodiment.

FIG. 3 is a schematic representation showing an exposure apparatus of the first embodiment.

FIGS. 4A and 4B are schematic representations showing a cam member of the first embodiment.

FIGS. 5A, 5B, 5C, and 5D are diagrams of the operation when the reticle clamp of the first embodiment clamps the reticle.

FIGS. 6A, 6B, 6C, and 6D are diagrams of the operation when the reticle clamp of the first embodiment releases holding of the reticle.

FIG. 7 is an oblique view showing reticle stage apparatus of a second embodiment.

FIG. 8 is an exploded oblique view showing a reticle stage apparatus of the second embodiment.

FIG. 9A is an oblique view and FIG. 9B is a cross-sectional view showing the stage part of the reticle stage apparatus of the second embodiment.

FIG. 10 is a drawing showing the positions of the reticle holders and reticle clamps in the reticle stage apparatus of the second embodiment.

FIGS. 11A and 11B are oblique views showing the reticle clamp of the second embodiment.

FIG. 12 is a schematic representation showing an exposure apparatus of the second embodiment.

FIGS. 13A and 13B are oblique views showing the cam member of the second embodiment.

FIGS. 14A, 14B, 14C, and 14D are diagrams showing the operation when the reticle clamp of the second embodiment clamps the reticle.

FIG. 15 is a flowchart showing an example of the manufacturing process for a semiconductor device.

DETAILED DESCRIPTION OF THE INVENTION

A first embodiment of a stage apparatus and the like of the present invention is described below, with references being made to FIGS. 1 to 6.

FIG. 1 is an oblique view showing the reticle stage apparatus 200 of the present invention.

The reticle stage apparatus (stage apparatus) 200 holds the reticle (plate member, mask) with the pattern (PA) surface downward, moves in a one-dimensional scan in the Y direction, and also makes fine movements in the X direction and in the rotational direction (.theta..sub.Z direction).

The reticle stage apparatus 200 has a stage part 203, which is driven through a prescribed stroke in the Y direction over the reticle table (base part) that is held by a column 201.

The stage part (movement member) 203 has a reticle coarse movement stage 206, which is driven in the Y direction by a pair of Y linear motors 205, and a reticle fine movement stage 208 that is finely driven in the X, Y, and .theta..sub.Z directions over the reticle coarse movement stage 206 by a pair of X voice coil motors 207X and a pair of Y voice coil motors 207Y.

Each of the Y linear motors 205 is provided with a stator (second movement member) 205a extending in the Y direction and supported in a floating manner by a plurality of air bearings (air pads) 209, and an stator (second movement member) 205b, provided in correspondence to the stator 205a, and which is fixed to the reticle coarse movement stage 206 via a linking member 231. For this reason, by the law of preservation of motion, in response to the +Y-direction movement of the reticle coarse movement stage 206, the stator 205a moves in the -Y-direction. By the movement of this stator 205a, the repelling force accompanying the movement of the reticle coarse movement stage 206 is cancelled out, and it is possible to prevent a change in the center of gravity.

The reticle coarse movement stage 206 is such that it is guided by a pair of Y guides 232, which are fixed to the upper surface of an upper protruding part formed at the center part of the reticle table 202 and which extend in the Y direction. The reticle coarse movement stage 206 is supported in a non-contacting manner on the Y guides 232 by air bearings, which are not illustrated.

The reticle fine movement stage 208 has an aperture that opposes the pattern PA of the reticle R, the reticle R being supported by vacuum chucking with the pattern downward, via the reticle holder (placement surface) 211, which is planar and disposed around the periphery of the aperture. Four reticle clamps 300 are disposed on the ends of the X-direction ends of the reticle holder 211 (two at each end).

The reticle clamps 300 for mechanically holding the reticle R by pressing from above, for the purpose of supplementing the insufficiency in the vacuuming chucking force on the reticle R by the reticle holder 211. The reason that the reticle clamps 300 at each of the X-direction ends of the reticle holder 211 is to avoid interference with the reticle R, which is placed on the reticle holder 211 and transported in the Y direction. Therefore, as long as there it would not hinder the transport of the reticle R, the reticle clamps 300 can alternatively be disposed at the Y-direction ends of the reticle R. The number of reticle clamps 300 to provide can be decided in accordance with the amount of pressing force required to hold the reticle R. However, to prevent distortion of the reticle R by the pressing force, it is desirable that they be disposed uniformly with respect to the reticle R (for example, at the four corners).

A pair of Y-direction moving mirrors 233a, 233b formed by corner cubes, is fixed at the -Y-direction end of the reticle fine movement stage 208, and an X-direction moving mirror 234 formed by a planar mirror extending in the X direction is fixed at the +X-direction end of the reticle fine movement stage 208. Three laser interferometers 235a to 235c (refer to FIG. 3) provided at the outer part with respect to these moving mirrors 233a, 233b, and 234 measure the distance to each mirror, so as to measure the X, Y, and .theta..sub.Z (rotational direction) positions with high accuracy. Also, the position measurement information of the reticle fine movement stage 208 (that is, the position information of the reticle R) is sent to the main control system 70.

Next, the configuration of the reticle clamps (fixing apparatuses) 300 is described below in detail. FIG. 2A is an oblique view showing the reticle clamp 300, this showing the condition in which the reticle R held by pressing. FIG. 2B is an exploded oblique view of the reticle clamp 300.

As shown in FIG. 2B, the reticle clamp 300 is formed by a base part 310, a pad part 320, a link part 330, sliding guide parts 340, a clamping spring part 350, and a follower part 360.

The base part 310 is provided at both X-direction ends of the reticle holder 211. A pin 312 is provided in a channel part 311, which is formed in substantially a channel shape along the X direction. The pad part 320 is held in the channel part 311, and there is mating of the pin 312 with the pin hole 321 of the pad part 320, as described later, so that the pad part 320 is rotatably supported.

To both sides of the base part 310 are provided guide insertion holes 313 along the X direction for the purpose of inserting the sliding and fixing the guide parts 340. Therefore, when the sliding guide parts 340 are inserted into the guide insertion holes 313, the two sliding guide parts 340 are fixed in the condition of extending in the X direction. Also, the sliding guide parts 340 are formed by rod members 341, onto one end of which is provided a stopper part 342 formed with a diameter that is larger than that of the rod member 341.

Two finger parts 314 are formed on the upper surfaces of the base part 310. The finger parts 314 are formed so as to be substantially triangular viewed from the side, having an inclined surface 314a which increases in height moving towards the reticle R in the X direction, and a surface 314b, which is substantially perpendicular to the reticle R.

The pad part 320 is made of a substantially triangular member, on one vertex of which (the linear motor side) is formed a pin hole 321. As described above, the pin hole 321 mates with the pin 312 of the base part 310, and is housed within the channel part 311 of the base part 310, being rotatably supported. Therefore, the pad part 320 is disposed substantially perpendicularly with respect to the X-direction end surface of the reticle R.

A contacting part 322 which makes contact with the reticle R placed on the reticle holder 211 is provided on the lower surface of the pad part 320. The contacting part 322 is made of a springy body 322a, so that it does not damage the reticle R which it contacts. In addition to sponge and rubber, it is possible to use a spring or springy hinge mechanism as the springy body 322a. It is desirable to make the width of the contacting part 322 being such that it does not interfere with the channel part and the like of the base part 310, thereby making the surface area of contact with the reticle R large, and pressing on the reticle R uniform.

The other vertex part at the top is formed so as to be bifurcated in the X direction, with pin 323 formed in a part thereof.

The link part 330 formed by a straight member has pin hole parts 331 and 332 at each end, the pin hole 331 mating with the above-described pin 323 of the pad part 320, so as to provide support in a rotatable manner. Additionally, the other pin hole 332 mates with the pin 356 of the clamping spring part 350, so as to provide rotatable support thereto.

The clamping spring part 350 is formed by a body part 351, a linking part 352 and a spring part 353, and has a structure such that the body part 351 and the linking part 352 are linked via the spring part 353.

The body part 351 has two holes 355 that mate with the sliding guide parts 340, so that by the mating of the two sliding guide parts 340 fixed to the base part 310 with these holes 355, the slide guide parts 340 are movably supported in the X direction along the slide guide parts 340. Holes 357, which mate with the follower part 360, are provided at the upper part of the body part 351.

The linking part 352 is formed as a channel, having a pin therewithin which mates with the pin hole 332 of the link part 330.

The spring part 353 is configured by a springy hinge mechanism that is machined using electric discharge machining using the wire-cut method, and supports the link part 353 so as to enable its movement in the X direction relative to the body part 351. By the resilience of the spring part 353 force is applied that holds the reticle R. Therefore, by adjusting the spring constant of the spring part 353, it is possible to adjust the pressing force of the reticle clamp 300. The spring part 353 is not restricted to being a springy hinge mechanism, but can also be a coil spring or leaf spring or the like having resilience.

The follower part 360 is formed by a body part 361, pins 352 provided at both ends of the body part 361, a cam follower 363 provide at the upper part of the body part 361, a leaf spring 364 extending from the body part 361 in the direction of the reticle R, and two support plates 365, which are disposed so as to overlap the leaf springs 364 at the bottom surface side and so as to restrict the deformation of the leaf springs 364 in the downward direction.

The follower part 360, by the pins 362 provided at both ends of the body part 361 mating with the holes 357 of the clamping spring part 350, rotatably supports the clamping spring part 350. Also, by the contact between the body part 361 of the follower part 360 and the body part 351 of the clamping spring part 350, restriction so as to not rotate above a prescribed amount is achieved. Specifically, the leaf springs 364 are prevented from rotating downward from the horizontal position (refer to FIG. 5 and FIG. 6).

A rectangular hole 364a that mates with the finger parts 314 of the base part 310 is provided in the end of each of the two leaf springs (holding apparatuses) 364. A channel-shaped cutout part 365a is provided at the end parts of the two support plates 365, in parts that are opposite the holes 364a of the leaf springs 364.

A bearing 363a for the purpose of alleviating friction of contact with the cam member 400, which is described below, is provided on the cam follower 363.

Next, an embodiment in which the above-described reticle stage apparatus 200 is applied to an exposure apparatus 100 is described below. FIG. 3 is a schematic representation showing the exposure apparatus 100.

The exposure apparatus 100 is a step-and-scan type of scanning exposure apparatus, a so-called scanning stepper, in which exposure illumination (exposure light) EL is shined onto a reticle R as the reticle R and the wafer (plate member, substrate) W are caused move relatively in one dimension (direction), so that a patterns (circuit pattern or the like) formed on the reticle R is transferred to the wafer W via a projection optical system 40.

The exposure apparatus 100 is formed by an exposure illumination system 10 that illuminates the reticle R with the exposure illumination EL, a reticle stage 200 that holds the reticle R, a projection optics system 200 that shines exposure illumination light EL emitted from the reticle R onto the wafer W, a wafer stage apparatus 50 that holds the wafer W, and a main control system 70 that performs overall control of the operation of the exposure apparatus 100.

The exposure illumination system 10 has an optical integrator for the purpose of shining the exposure illumination light EL emitted from the light source 12 onto the reticle R with a distribution that is substantially uniform over a prescribed illumination region thereof.

A vacuum ultraviolet beam in the wavelength range from approximately 120 nm to approximately 190 nm, for example an ArF excimer laser (ArF laser) having an oscillation wavelength of 193 nm, a fluorine laser (F.sub.2 laser) having an oscillation wavelength of 157 nm, a krypton dimer laser (Kr.sub.2 laser) having an oscillation wavelength of 146 nm, or an argon dimer laser (Ar.sub.2 laser) having an oscillation wavelength of 126 nm or the like can be used as the exposure illumination light EL.

The reticle stage apparatus 200 is provided directly below the exposure illumination system 10. The specific configuration of the reticle stage apparatus 200 is as described above.

The stage part 203 of the reticle stage apparatus 200 holds the reticle R, with the pattern PA facing downward and moves in a one-dimension scan in the Y direction, and midway in the movement path thereof is a loading region (second region) A2 in which the reticle R is placed onto the reticle holder 211, an unloading region (third region) A3 in which the reticle R is removed from the reticle holder 211, and an exposure region A4 in which the exposure illumination light EL is shined onto the reticle R. Normally, the loading region A2 and the unloading region A3 are coinciding regions (which is hereafter called the loading/unloading region A0) and, as shown in FIG. 3, because of the dimensional restrictions of the apparatus, there is partial overlapping of the loading/unloading region A0 and the exposure region A4. Also the clamp drive region (first region) A1, to be described below, is also included midway in the movement path of the stage part 203.

A cam member 400 that serves as a cam apparatus (conversion apparatus) C which is configured together with the above-described reticle clamp 300 is provided at the upper part within the loading/unloading region A0. The cam member 400 is fixed, via an elevator apparatus to be described later, to either the reticle table 202 or the column 201.

FIG. 4 is a schematic representation showing the cam member 400. The cam member 400 is formed in substantially a channel shape, by rotatably linking the end parts of each of the two members 401a and 401b formed in L shapes so that they are symmetrical.

Grooves 402a and 402b, into which the cam follower 363 of the above-described follower part 360 enters, are formed on the lower surface of the members 401a and 401b. The widths of the grooves 402a and 402b are formed so as to be large at the end parts of the members 401a and 402a, and are made gradually narrower toward the +Y direction so that they are slightly wider than the width of the end parts of the members 401a and 401b. The grooves 402a and 402b are formed so as to veer inward at the end parts, veering gradually outwards as they progress in the +Y direction, after which they reach a width dimension in the part that is parallel to the Y direction that is greater than the reticle R. (Hereinafter, the region in which the grooves 402a and 402b veer inward and then gradually outward is referred to as the clamp drive region A1). Therefore, when the cam follower 363 moves from the left side of the paper in FIG. 4 toward the right in the +Y direction, it enters the widely formed end parts of the grooves 402a and 402b. When there is further movement in the +Y direction, as the clamp drive region A1 is passed, it is guided so as to move from inside to outside.

A spring (shock-absorber) 403 is provided between the members 401a and 402a, at the end of the cam apparatus 400. This rotatably links the members 401a and 401b and, by providing the spring 403, it is possible to make fine movement relative to the cam follower 363 that comes into the grooves 402a and 402b, so that there is a reduction in the shock and friction between the cam follower 363 and the grooves 402a and 402b.

An elevator apparatus (pull-back apparatus) 410 that causes upward movement of the cam member 400 is provided on the cam member 400. The elevator apparatus 410 is formed, for example, by an air cylinder or the like and, by causing the cam member 400 to rise, the cam member 400 and the reticle clamp 300 are separated, so that it is not possible for the cam follower 363 to enter the grooves 402a and 402b. In this manner, the cam member 400 can be pulled back from the loading/unloading region A0, or can be made to intrude into the cam member 400.

Returning to FIG. 3, the projection optical system 40 is a system of a plurality of lenses and reflective mirrors made from fluoride crystals such as lithium fluoride, hermetically sealed in a projection system housing (lens tube). The projection lens system reduces the illumination light shined through the reticle R by a projection ratio of .beta. (.beta. being, for example, 1/4), and forms an image of the pattern PA of the reticle R onto a prescribed region (shot region) of the wafer W. Also, the various elements of the projection lens system of the projection optical system 40 are supported in the projection system housing by a respective holding member, each holding member being annular, for example, so as hold each element around its periphery (none are illustrated).

The wafer stage apparatus (stage apparatus) 50 is made up of elements such as a wafer holder 52 that holds the wafer W, and a wafer stage 53 that can move within the XY plane. The wafer holder 52 is supported by the wafer stage 53, and holds the wafer by vacuum chucking. The wafer stage 53 is a pair of blocks that can move in mutually perpendicular directions, superposed on the base 54, and is driving in the XY plane by a drive section that is not illustrated.

Externally provided laser interferometer measuring apparatuses successively detect the X-direction and Y-direction positions of the wafer stage 53, and output these to the main control system 70.

An X moving mirror 56X, formed by a planar mirror, is provided on at the -X direction of the wafer holder 52 so as to extend in the Y direction. A distance measurement beam from the X-axis laser interferometer 57X is shined substantially perpendicularly onto the X moving mirror 56X, and the reflected light therefrom is received by the X-axis laser interferometer 57X, so as to detect the X position of the wafer W. The Y position of the wafer W is detected by a Y-axis laser interferometer 57Y having substantially the same configuration.

By the movement of the wafer stage 53 within the XY plane, the projection position (exposure position) of the pattern PA of the reticle R is positioned at any arbitrary position on the wafer W, and transfers by projection to the wafer W the image of the pattern PA of the reticle R.

The main control system 70 performs overall control of the exposure apparatus 100. For example, it controls the exposure light amount (amount of exposure light illumination), and the positions of the reticle stage apparatus 200, described later, and the wafer stage 53, and performs repeated exposure operations that transfer the pattern PA of the reticle R onto shot regions of the wafer W. The main control system 70 is provided with a processor 71, which performs various calculations, and also a storage unit 72, which records various information.

Next, a method of performing exposure processing that transfers the pattern PA formed on the reticle R to the wafer W by shining exposure illumination light EL onto the reticle R using the exposure apparatus 100 having the above-noted configuration is described below.

The exposure processing method of this embodiment has a step of loading the reticle R onto the reticle stage apparatus 200, a step of pressure holding the reticle R by the reticle clamps 300, a step of releasing the holding of the reticle R by the reticle clamps 300, and a step of unloading the reticle R from the reticle stage apparatus 200. Holding the reticle R and releasing the holding of the reticle R by the reticle clamps 300 will operate with the stage part 203 passing through the clamp drive region A1, as described bellow. The step of loading the reticle R onto the reticle stage apparatus 200 will now be described. Before the reticle R is placed (in the initial condition), the reticle stage apparatus 200 is at the exposure region (A4). The reticle clamps 300 are in the condition in which the pad parts 320 are either flipped up (refer to FIG. 5A) or lowered (refer to FIG. 5D). Also, the cam member 400 is disposed within the loading/unloading region A0.

By a command from the main control system 70, the stage part 203 moves in the +Y direction, moving from the exposure region A4 up to the loading/unloading region A0, where it stops. Accompanying the movement of the stage part 203, the cam followers 363 of the reticle clamps 300 enter the grooves 402a and 402b of the cam member 400. The cam followers 363 moves first to the inside (direction approaching the reticle R), but when the stage part 203 stops at the loading/unloading region A0, all of the cam followers 363 pass through the clamp drive region A1, and move to the outside (direction moving away form the reticle R). By doing this, all of the reticle clamps 300 are held in the condition in which the pad parts 320 are in the flipped up condition. The specific operation of the reticle clamps 300 will be described later. The bearing 363a provided on the cam follower 363 and the spring 403 provided on the cam member 400 reduce the contact friction between the cam follower 363 and the grooves 402a and 402b, so that the cam follower 363 moves smoothly in the grooves 402a and 402b.

By a reticle transport apparatus that is not illustrated, a reticle R is transported from outside, placed on the reticle holder 211 above the stage part 203, and the reticle R is vacuum chucked by the reticle holder 211.

Next, in the step in which the reticle R is held by pressure by the reticle clamps 300, -Y-direction movement is done with the reticle R placed on the stage part 203. Accompanying the movement of the stage part 203, when the cam followers 363 of the reticle clamps 300 pass through the clamp drive region A1 they gradually move into the grooves 402a and 402b of the cam members 400. In this manner, by the cam follower 363 moving from the outside to the inside, the reticle clamps 300 are driven, and the reticle R is successively clamped by pressing (clamping).

When the stage part 203 moves further in the -Y direction, by it moving from the loading/unloading region A0 to inside the exposure region A4, the cam followers 363 of the reticle clamps 300 successively are pulled out from the grooves 402a and 402b of the cam members 400. However, the pressure holding of the reticle R by the reticle clamps 300 is maintained by the action of the leaf springs 364.

The operation when the reticle R is held (pressed) by the reticle clamps 300 is described below in detail. FIG. 5 is a drawing showing the operation when the reticle R is held by pressing.

First, as shown in FIG. 5A, the reticle R is placed on the reticle holder 211 on the stage part 203 and held by vacuum chucking. When this is done, because the reticle clamps 300 are in the condition in which the pad parts 320 are flipped up, there is no interference between the reticle R and the reticle clamps 300. After the holding of the reticle R by vacuum chucking, a force directed toward the reticle R side acts on the cam followers 363. That is, this is the case in which the cam followers 363 enter the clamp drive region A1, and start to move along the grooves 402a and 402b of the cam members 400, toward the inside (the direction approaching the reticle R).

When the force acts on the cam followers 363 in the direction toward the reticle R (toward the left in the drawing), a moment acts that rotates the cam follower 363 about the pin 362 and, as shown in FIG. 5B, because the follower part 360 does not rotate relative to the clamping spring part 350, the follower part 360 acts as one with the clamping spring part 350 and starts to move toward the base part 310, along the sliding guide parts 340. Accompanying this movement, the force that is caused to act on the cam follower 363 is transmitted to the pad part 320 via the link part 330, causing the link part 320 to rotate about the pin hole 321. Also, because the pad parts 320 rotated smoothly, there is almost no deformation of the spring part 353 of the clamping spring part 350.

Additionally, when a force acts on the cam follower 363 in the direction toward the reticle R side, as shown in FIG. 5C, the leaf spring 364 of the follower part 360 is butted against the finger part 314 provided at the upper surface of the base part 310, and deforms so as to bend upward along the inclined surface of the finger part 314. Because a channel-shaped cutout 365a is provided in the support plate 365, it does not butt up against the finger part 314, and moves toward the reticle R, avoiding the finger part 314. The pad part 320 rotates further about the pin hole 321, and the contacting part 322 comes into contact with the reticle R. By the contacting part 322 coming into contact with the reticle R, because the pad parts 320 cannot rotate further about the pin hole 321, the spring part 353 of the clamping spring part 350 begins to deform.

Then, further force acts on the cam follower 363 in the direction toward the reticle R side. That is, the cam follower 363 passes the clamp drive region A1 is in the condition in which it is at the innermost position. When this occurs, as shown in FIG. 5D, the leaf spring 364 rises over the finger part 314 provided at the upper surface of the base part 310, the hole 364a in the leaf spring 364 mating with the finger part 314, and the leaf spring 364 deformation returning to the initial condition (flat condition). The spring part 353 of the clamping spring part 350 further deforms and applies a strong pressing force on the reticle R via the pad part 320.

Finally, in this condition the force on the cam follower 363 directed toward the reticle R is released. That is, the cam follower 363 of the reticle clamp 300 go into the condition in which the cam member 400 pulls out of the grooves 402a and 402b. When the force acting on the cam follower 363 is released, by the spring force of the spring part 353 of the clamping spring part 350 a force acts to move the clamping spring part 350 in the direction of the linear motor side. However, the leaf spring 364 of the follower part 360 linked to the clamping spring part 350 restricts the movement of clamping spring part 350 toward the linear motor. That is, because the hole 364a of the leaf spring 364 mates with the finger part 314 of the base part 310, even if the force acting on the cam follower 363 in the direction of the reticle R is released, by the action of the leaf spring 364 of the follower part 360, the deformation of the spring part 353 is not released, and the condition of pressing the reticle R is maintained.

The reticle clamps 300 hold the reticle R in this manner, with a strong pressing force.

Next, the in the step of performing exposure, before starting the exposure processing the cam member 400 is caused to pull back from the loading/unloading region A0. That is, the elevator apparatus 410 is driven so as to cause the cam member 400 to rise, thereby causing it to move outside the loading/unloading region A0.

After the cam member 400 is caused to pull back, as done in the past, exposure illumination light (exposure light) EL is shined onto the reticle R as the reticle R and the wafer W are caused to move relatively in one direction, so as to transfer onto the wafer W, via the projection optical system 40, a pattern PA formed on the reticle R.

In this manner, the performing of exposure processing after causing the cam member 400 to pull back is in order to prevent the release of the pressing force of the reticle clamps 300 on the reticle R during exposure processing. That is, during exposure processing the stage part 203 moves reciprocally at high speed. As described above, there is a partial overlapping between the exposure region A4 and the loading/unloading region A0. For this reason, if the cam member 400 remains in the loading/unloading region A0, during exposure processing part of the plurality of reticle clamps 300 enter the grooves 402a and 402b of the cam member 400, pass by the clamp drive region A1, and the pressing that holds the reticle R is released.

In this manner, by causing the cam member 400 to pull back from the loading/unloading region A0 before the start of exposure processing, it is possible to prevent the risk of the release of the reticle clamps 300 during exposure processing before it occurs.

Next, the step of releasing the holding of the reticle R by the reticle clamps 300 is described below.

When the exposure processing is completed, the elevator apparatus 410 is driven so as to cause the cam member 400 to move into the loading/unloading region A0. When this is done, the stage part 203 is caused to move in the -Y direction so as to avoid interference with the cam member 400.

Then the stage part 203 is moved in the +Y direction, moving from the exposure region A4 to a position within the loading/unloading region A0. Accompanying the movement of the stage part 203, the cam followers 363 of the reticle clamps 300 enter the grooves 402a and 402b of the cam member 400, and successively pass through the clamp drive region A1, moving from the inside (reticle R side) to the outside. In this manner, by causing the cam followers 363 to move from the inside to the outside, the reticle clamps 300 are driven, and the pressing forces holding the reticle R are successively released.

The operation of releasing of the holding (pressure) on the reticle R by the reticle clamps 300 is described below in detail. FIG. 6 is a drawing showing the operation when the holding of the reticle R is released.

First, as shown in FIG. 6A, a force is caused to act on the cam followers 363 in the direction that moves them away from the reticle R (to the right in the drawing). That is, the cam followers 363 of the reticle clamps 300 enter the grooves 402a and 402b of the cam member 400 and enter into the clamp drive region A1, the condition in which movement to the outside (in the direction away from the reticle R) begins.

When force is caused to act on the cam follower 363 in the direction away from the reticle R, as shown in FIG. 6B a moment acts that cause the cam follower 363 to rotate about the pad part 320, and the follower part 360 begin to rotate about the pad part 320.

When the follower part 360 rotate a prescribed angle or greater about the pad part 320, as shown in FIG. 6C the hole 364a of the leaf spring 364 rises over the perpendicular surface 314b of the finger part 314, and the mating between the leaf spring 364 and the finger 314 is released. By this occurring, it becomes possible to release the deformation of the spring part 353, and the follower part 360 and clamping spring part 350 act as one in moving along the sliding guide part 340 towards the right side as shown in the drawing. Then, accompanying this movement, because the link part 330 moves to the right side as shown in the drawing, the pad part 320 begins to rotate about the pin hole 321.

Then, the follower part 360 and the clamping spring part 350 return to the initial position. That is, the cam follower 363 passes through the clamp drive region A1 and goes into the condition in which it has moved to the most outside position. When this happen, as shown in FIG. 6D the pad part 320 flips up and away from the reticle R.

By doing the above, the pressing of the reticle clamp 300 that hold the reticle R is released.

Finally, in the step of unloading the reticle R from the reticle stage apparatus 200, after or as the same time as the holding of the reticle R by the reticle clamps 300 is released, the vacuum chucking of the reticle R by the reticle holder 211 is released. Then, by a reticle transport apparatus that is not illustrated, the reticle R is transported from the top of the reticle stage apparatus 200 towards the outside. In the same manner as when the reticle R is transported onto the reticle stage apparatus 200, because the pad parts 320 of the reticle clamps 300 are in the flipped up condition, the reticle R can be transported out without interference.

By doing the above, it is possible not only to hold the reticle R firmly on the reticle stage apparatus 200, but also to maintain that holding during the exposure processing. Also, the pressing by the reticle clamps 300 that hold the reticle R is released only when the reticle R is placed on and removed from the reticle stage 200.

By holding the reticle R firmly on the reticle stage apparatus 200, even if the reticle stage apparatus 200 is moved with high acceleration, the reticle R does not shift, enabling highly precise transfer of the pattern PA onto the wafer W.

Furthermore, it is desirable to provide a detection apparatus for the purpose of verifying that the pressing by the reticle clamps 300 that holds the reticle R is released. For example, providing a reflective mirror on the upper surface of the link part 330 of the reticle clamp 300 and installing a laser interferometer above the exposure region A4. This having been done, by measuring the height of the upper surface of the link part 330 that passes beneath the laser interferometer, it is possible to detect the operating condition of the reticle clamp 300. Alternatively, it is possible to measure the position of the body 351 of the clamping spring part 350, or to provide a limit switch that is actuated when the body 351 has moved to the rearmost position.

In this manner, by detecting the operating condition of the reticle clamp 300, because the reticle R is held securely on the reticle stage apparatus 200, it is possible to avoid problems caused by release of a reticle clamp 300 during exposure processing.

Next, a second embodiment of a stage apparatus and the like according to the present invention is described below, with references made to FIGS. 7 to 14.

FIG. 7 is an oblique view showing the reticle stage apparatus 500 of the present invention, FIG. 8 is an exploded oblique view of the reticle stage apparatus 500, FIG. 9 is an oblique view and a cross-sectional view showing the stage part 520, and FIG. 10 is a drawing showing the positions of the reticle holders 525 and reticle clamps 600. Constituent elements that are the same as in the first embodiment are assigned the same reference numerals and are not described herein.

The reticle stage apparatus 500, as shown in FIG. 7, has elements such as a reticle table 510, a stage part 520, which is driven through a prescribed stroke in the Y direction over the reticle table 510, a frame-shaped member 530 disposed so as to surround the stage part 520, and a reticle stage drive system (linear motor 540 and voice coil motor 550) that drives stage part 520.

The reticle table (base part) 510 is supported substantially horizontally by a support member that is not illustrated. The reticle table 510, as shown in FIG. 8, is formed from an approximately planar member, in the substantially center position of which is formed a protrusion 516a. Additionally, in the substantially center part of the protrusion 516a there is formed a rectangular aperture 516b having the X-axis direction as its longitudinal direction so as to pass the exposure illumination light EL and so as to be a through hole in the Z direction.

As shown in FIG. 9A, the stage part (movement member) 520 is formed by such elements as a stage body 522 that is substantially rectangular in shape, and four extension parts 524, which are provided so as to extend in the Y direction from the stage part 520. On the lower surfaces of each of the four extension parts 524 are formed static pressure air bearings. By doing this, the stage part 520 is supported in non-contact, floating manner, via a clearance of several microns over the reticle table 510.

A pair of Y-direction moving mirrors 233a, 233b formed by corner cubes, is fixed at the -Y-direction end of the stage part 520, and laser interferometers 235a to 235c (refer to FIG. 12) provided at the outer part measure the Y-direction position of the Y moving mirrors 233a and 233b, so as to measure the Y-direction position of the stage part 520 (reticle R) with high precision.

In substantially the center part of the stage body 522 is provided a stepped aperture 523 that forms a path for the exposure illumination light EL, the step part of this stepped aperture 523 (part that is one step down) being provided with a reticle holder (placement surface) 525 that vacuum chucks the reticle R from the bottom. Additionally, four reticle clamps 600 are provided at both edges of the stepped aperture 523 (two at each edge). The configuration of the reticle clamps 600 is described later.

As shown in FIG. 10, the reticle holder 525 has vacuum chucking surfaces 525a and 525b formed so as to be rectangular along the Y direction at the outside of the stepped aperture in the X direction, these holding the regions of the reticle R at the X-direction edges by vacuum chucking from the bottom of the reticle. It is possible to used electrostatic chucking in place of vacuum chucking, and further possible to use a combination of electrostatic chucking and vacuum chucking.

Four reticle clamps 600 are provided further to the outside of the reticle holders 525 in the X direction, and a region at ends of the reticle R in the X direction that is vacuum chucked by the reticle holders 525 is