JP4868113B2 - Support apparatus, stage apparatus, and exposure apparatus - Google Patents

Description

  The present invention relates to a support device, a stage device, and an exposure device, and more specifically, a support device that supports a second object relative to a first object, a stage device including a stage that can move in a two-dimensional plane, and the stage device Relates to an exposure apparatus comprising:

  In recent years, a projection exposure apparatus such as a stepper or a scanning stepper includes a table that holds a wafer, a stage that holds the table and moves in a two-dimensional plane, and a linear motor that drives the stage. The linear motor type stage apparatus which has has become mainstream.

  In this type of stage apparatus, the table is supported with respect to the stage via a fine movement mechanism such as three voice coil motors or three electromagnets, and the fine movement mechanism causes the table to move on the stage with respect to the moving surface of the stage. Fine movement is possible in the direction of inclination and in the direction of three degrees of freedom perpendicular to the moving surface. The fine movement mechanism and the linear motor realize driving of the table in the direction of six degrees of freedom (see, for example, Patent Document 1).

  In this type of stage apparatus, in addition to reducing the weight of the table, it is important to realize driving of the table with high acceleration.

  In these apparatuses, a proposal has been made to adopt a self-weight canceller as a mechanism for supporting the table (see, for example, Patent Document 2). However, in the conventional self-weight canceller, if the table is allowed to move in the horizontal direction, the rigidity in the direction of gravity cannot always be sufficiently increased.

International Publication No. 02/080185 Pamphlet JP 2000-56483 A

The present invention has been made under the circumstances described above. From the first viewpoint, the present invention is a support device for supporting a second object (WTB) with respect to a first object (31), wherein A fixed part (90) connected to the object; and a movable part (190) movable in the gravitational direction with respect to the fixed part, wherein the movable part moves a part of the second object in the gravitational direction. seen sandwiched in a non-contact from both sides, the second said connecting portion moving in a plane perpendicular to the direction of gravity with respect to some of which is connected to the second object in the allowed state of the object (74A, 74B, 70A , 70B, 72a to 72d).

  According to this, the movable part that can move in the gravitational direction with respect to the fixed part connected to the first object is attached to the second object in a state where a part of the second object is sandwiched from both sides in the gravitational direction without contact. Since the connection part to be connected is included, it is possible to set the rigidity of the connection part in the gravitational direction to be high with at least the movement of the second object in a plane perpendicular to the gravitational direction. Moreover, since the support device is not connected to the second object in contact with the second object, the weight of the entire second object (including the structure directly connected to the second object) can be reduced.

  From a second viewpoint, the present invention provides a stage (31) movable in a two-dimensional plane; and a support device according to the present invention for supporting a table (WTB) for holding a substrate (W) on the stage. And a first stage apparatus.

  According to this, the table can be supported with respect to the stage with high rigidity in the gravity direction and at least allowed to move in a plane perpendicular to the gravity direction of the table, and the table is perpendicular to the gravity direction. Even when driving in a smooth plane, it is possible to achieve high acceleration.

According to a third aspect of the present invention, there is provided an exposure apparatus comprising the first stage apparatus of the present invention, wherein the substrate (W) held on the stage is exposed.

  According to this, by providing the stage apparatus of the present invention, it is possible to improve the exposure performance.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows a schematic configuration of an exposure apparatus 10 according to an embodiment. The exposure apparatus 10 is a batch exposure type projection exposure apparatus such as a stepper.

  The exposure apparatus 10 includes an illumination unit IOP, a reticle stage RST that holds a reticle R, a projection optical system PL, and a wafer stage WST that holds a wafer W as a substrate and moves in an XY two-dimensional direction in an XY plane. 50, a control system thereof, and a column 34 for holding the projection optical system PL.

The illumination unit IOP includes a light source and an illumination optical system, and illumination light as an energy beam in a rectangular or arcuate illumination region defined by a field stop (also referred to as a mask king blade or a reticle blind) disposed therein. IL is irradiated, and the reticle R on which the circuit pattern is formed is illuminated with uniform illuminance. Here, as the illumination light IL, an emission line in the ultraviolet region from an ultrahigh pressure mercury lamp (g-line with a wavelength of 436 nm, i-line with a wavelength of 365 nm, etc.) is used. However, vacuum ultraviolet light such as KrF excimer laser light (wavelength 248 nm), ArF excimer laser light (wavelength 193 nm), or F ₂ laser light (wavelength 157 nm) may be used instead.

  The reticle stage RST is disposed below the illumination unit IOP. In practice, reticle stage RST is placed on the upper surface of projection optical system PL (however, in FIG. 1, for convenience of illustration, reticle stage RST and projection optical system PL are shown apart from each other). Specifically, reticle stage RST can be finely driven in the X-axis direction, Y-axis direction, and θz direction while holding reticle R on the base fixed to the upper surface of projection optical system PL. Note that the reticle stage RST may be configured to have a function of simply holding the reticle R, and the reticle R may not be driven.

  A part of the reticle R is provided with a pair of alignment marks. In the present embodiment, before the exposure, the pair of alignment marks are measured and positioned using a reticle alignment system (not shown).

  As the projection optical system PL, here, a bilateral telecentric reduction system and a refractive optical system including a plurality of lens elements having a common optical axis in the Z-axis direction are used. The projection magnification β of the projection optical system PL is, for example, 1/4 or 1/5. Therefore, as described above, when the reticle R is illuminated by the illumination light IL from the illumination unit IOP, the circuit pattern in the illumination area formed on the reticle R is illuminated on the wafer W by the projection optical system PL. Is reduced and projected onto the irradiation area (exposure area) of the illumination light IL conjugate with the light, and a reduced image (partial equality image) of the circuit pattern is transferred and formed.

  A flange FLG is provided at substantially the center in the height direction of the lens barrel of the projection optical system PL.

  The column 34 has three legs 32b (the legs on the back side of the paper are not shown) whose lower ends are fixed to the floor F, and a top plate supported above the floor F by the legs 32b. Part 32a. An opening 34a is formed in the central portion of the top plate portion 32a so as to penetrate in the vertical direction (Z-axis direction).

  The projection optical system PL has three suspension support mechanisms 37 (one suspension support mechanism on the back side of the drawing is not shown) fixed at one end to the lower surface side of the top plate portion 32a constituting the column 34. Suspended and supported by the flange FLG. Each of these suspension support mechanisms 37 includes a coil spring 36 and a wire 35 which are flexible connection members. Since the coil spring 36 vibrates like a pendulum in the direction perpendicular to the optical axis, the vibration isolation performance in the direction perpendicular to the optical axis of the projection optical system PL (the vibration of the floor is transmitted to the projection optical system PL). Performance). Also, it has high vibration isolation performance in the direction parallel to the optical axis.

  Further, a convex portion 134a is formed in the vicinity of the central portion in the Z-axis direction of each leg portion 32b of the column 34, and a drive mechanism 40 is provided between each convex portion 134a and the outer peripheral portion of the flange of the projection optical system PL. Is provided. This drive mechanism includes a voice coil motor that drives the projection optical system PL in the radial direction of the lens barrel, and a voice coil motor that drives the projection optical system PL in the optical axis direction (Z-axis direction). With these drive mechanisms, the projection optical system PL can be moved in the direction of six degrees of freedom.

  The flange FLG of the projection optical system PL is provided with an acceleration sensor (not shown) for detecting the acceleration in the direction of 6 degrees of freedom of the projection optical system PL. Based on the acceleration information detected by the acceleration sensor, A main controller (not shown) controls the drive of the voice coil motor of the drive mechanism 40 so that the projection optical system PL is stationary with respect to the column 34 and the floor surface F.

  From the lower surface of the flange FLG of the projection optical system PL, a ring-shaped measurement mount 51 is suspended and supported via three support members 53 (however, a support member on the back side of the paper surface is not shown). The three support members 53 are actually configured to include link members having flexure portions that can be displaced by five degrees of freedom other than the longitudinal direction of the support member 53 at both ends thereof, and the measurement mount 51 and the flange FLG. The measurement mount 51 can be supported with almost no stress between the two.

  The measurement mount 51 holds a wafer interferometer 58, an alignment system (not shown), a multipoint focal position detection system (not shown), and the like. As the alignment system, an image processing type sensor can be used, and this image processing type sensor is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-65603. Further, as the multipoint focal position detection system, for example, a focus sensor disclosed in Japanese Patent Laid-Open No. 4-215015 can be used.

  The stage apparatus 50 includes a wafer stage WST and a wafer stage drive system that drives the wafer stage WST.

  Wafer stage WST is levitated and supported on the upper surface of stage surface plate BS arranged horizontally below projection optical system PL via an air bearing or the like provided on the bottom surface thereof.

  Here, the stage surface plate BS is directly installed on the floor surface F, and the surface (upper surface) on the + Z side is processed so as to have a very high flatness, and the wafer stage WST. The movement reference plane (guide plane).

  As shown in FIG. 2, wafer stage WST includes stage 31 and wafer table WTB mounted via three self-weight cancellers 150 provided at three locations not on a straight line on stage 31. Yes. The three self-weight cancellers 150 are configured to support the wafer table WTB at three points on the stage 31 and each include a drive mechanism (such as a voice coil motor). By each drive mechanism, wafer table WTB is minutely driven in the three-degree-of-freedom directions of Z-axis direction, θx direction (rotation direction about X axis), and θy direction (rotation direction about Y axis). The configuration of the self-weight canceller 150 will be described in detail later.

Further, an X fine movement mechanism VX and a pair of Y fine movement mechanisms VY ₁ and VY ₂ are provided between wafer table WTB and stage 31. These X and Y fine movement mechanisms are, for example, a voice coil motor including a stator including an armature unit and a mover including a magnetic pole unit, and the respective stators are fixed to the upper surface of the stage 31. Each mover is fixed to the side surface of wafer table WTB. Among these, the X fine movement mechanism VX drives the wafer table WTB in the X axis direction, and the pair of Y fine movement mechanisms VY ₁ and VY ₂ moves the wafer table WTB in the Y axis direction and the θz direction (rotation direction around the Z axis). ) In two directions of freedom. Therefore, wafer table WTB can be moved in the direction of 6 degrees of freedom with respect to stage 31 by the drive mechanism, X fine movement mechanism VX, and a pair of Y fine movement mechanisms VY ₁ and VY ₂ provided in each of three dead weight cancellers 150. It has become.

  The stage 31 includes a frame member whose XZ cross section is rectangular, and a Y mover (not shown) is provided in the internal space of the frame member. A plurality of air bearings (not shown) are provided on the lower surface of the frame-like member, and the wafer stage WST is levitated and supported above the above-described guide surface via a clearance of about several μm via these air bearings.

  The Y mover constitutes a Y axis linear motor together with a Y stator 134Y whose longitudinal direction is the Y axis direction, and drives the stage 31 together with the wafer table WTB and the wafer W in the Y axis direction. Hereinafter, this Y-axis linear motor is also referred to as a Y-axis linear motor 134Y using the same reference numeral as that of the Y stator.

X movers 132X ₁ and 132X ₂ are fixed to one end and the other end of the Y stator 134Y in the Y-axis direction. The X mover 132X ₁ constitutes a first X axis linear motor together with the X stator 134X ₁ provided in the vicinity of the + Y side of the stage surface plate BS and having the X axis direction as the longitudinal direction. The X mover 132X ₁ constitutes a second X-axis linear motor together with an X stator 134X ₂ provided in the vicinity of the −Y side of the stage surface plate BS and having a longitudinal direction in the X-axis direction. In the following description, the first X-axis linear motor 134X ₁ , the second X-axis linear motor, and the second X-axis linear motor are denoted by the same reference numerals as those of the X stator. It shall also be referred to as a 134X _2.

In the present embodiment, wafer stage WST is driven along the X-axis direction together with Y-axis linear motor 134Y by _first and second X-axis linear motors 134X ₁ and 134X ₂ . In addition, the X-axis direction electromagnetic force (driving force) generated by the first and second X-axis linear motors 134X ₁ and 134X ₂ may be slightly changed to rotate wafer stage WST in the θz direction. it can.

As can be seen from the above description, in this embodiment, the Y-axis linear motor 134Y, the first and second X-axis linear motors 134X ₁ and 134X ₂ , the three self-weight cancellers 150, the X fine movement mechanism VX, a pair The Y fine movement mechanisms VY ₁ and VY ₂ constitute at least a part of the wafer stage drive system. Each component of the wafer stage drive system is controlled by a main controller (not shown).

  Wafer W is adsorbed and held on the upper surface of wafer table WTB via wafer holder 25 by vacuum adsorption (or electrostatic adsorption) or the like. Wafer holder 25 is held by suction on the entire back surface of wafer table WTB by vacuum suction.

  3A is an enlarged plan view showing the vicinity of wafer table WTB, and FIG. 3B is a cross-sectional view taken along line AA in FIG. 3A. As shown in FIGS. 3A and 3B, in this embodiment, grooves (non-penetrating slits) 41a and 41b having a predetermined depth are formed on the upper surface of the wafer table WTB near the outer periphery of the wafer holder 25. Is formed (not shown in FIG. 2). The groove 41a has a portion whose longitudinal direction is the Y-axis direction in plan view (viewed from above), a portion whose longitudinal direction is the direction intersecting the X-axis and the Y-axis, and a portion whose longitudinal direction is the X-axis direction. And have. Further, the groove 41b has a very elongated rectangular shape with the X-axis direction as the longitudinal direction in a plan view (viewed from above) with the X-axis direction as the longitudinal direction.

These grooves 41a and 41b are formed so as to be positioned between the X fine movement mechanism VX and the pair of Y fine movement mechanisms VY ₁ and VY ₂ and the wafer holder 25, and the X fine movement mechanism VX and the pair of Y fine movement mechanisms VY. _Since the propagation of the driving force due to ₁ and VY ₂ wraps around the lower portions of the grooves 41a and 41b and spreads to the wafer table WTB, the influence can be mitigated.

More specifically, as shown in FIG. 3C, when the grooves 41a and 41b are not formed on the wafer table WTB, the X fine movement mechanism VX (and the pair of Y fine movement mechanisms VY ₁ and VY _2). ) Is applied directly to the outer peripheral portion of the wafer holder 25 (the outer edge portion of the suction area). However, as in this embodiment, the driving force is applied to the wafer table WTB. By forming the grooves 41a and 41b in the groove 41a and 41b, as shown in FIG. 3D, the driving force generated by the X fine movement mechanism VX (the pair of Y fine movement mechanisms VY ₁ and VY ₂ ) It goes around the lower part and propagates to wafer table WTB.

  Returning to FIG. 1, the position information of wafer stage WST is always detected at a resolution of, for example, about 0.5 to 1 nm by wafer interferometer 58 that irradiates a length measurement beam onto the reflection surface provided on the side surface of wafer table WTB. ing.

More specifically, as shown in FIG. 4, the wafer interferometer 58 includes three double-pass interferometer units 58Y, 58X ₁ , 58X ₂ , and each of the interferometer units 58Y, 58X ₁ , 58X _{2 based on} the information on the position of the reflecting surface of the wafer table WTB with respect to the reflecting surface of the fixed mirror, that is, from the branch point of the length measuring beam and the reference beam branched in each interferometer unit The position information of the wafer table WTB (wafer W) is measured using the information on the difference in optical path length. Each interferometer unit 58Y, 58X ₁ , 58X ₂ is supported in a suspended state by the measurement mount 51 described above.

The side surface (side surface on the −X side) of wafer table WTB facing interferometer units 58X ₁ and 58X ₂ is divided into three regions in the Z-axis direction (vertical direction) as shown in FIG. The upper region (first region) and the lowermost region (second region) are planes parallel to the YZ plane, and the surfaces thereof are mirror-finished (hereinafter, each plane is referred to as a first reflecting surface 54a, a first plane). 2 is referred to as a reflective surface 54b). The central region (third region) is a plane inclined by a predetermined angle α ° (0 <α <90) with respect to the measurement beams WXF ₃ and WX ₃ (which will be described later), and the surface thereof. Is mirror-finished (hereinafter, the mirror-finished surface of the third region is referred to as a third reflecting surface 54c).

The interferometer unit 58X ₁ irradiates the first reflecting surface 54a with a length measuring beam WXF ₁ parallel to the X axis, and the second reflecting surface 54b with a length measuring beam WXF ₂ parallel to the X axis. The third measuring surface 54c is irradiated with a measurement beam WXF ₃ parallel to the X axis.

Further, the interferometer unit 58X ₁ is provided with a fixed mirror 56a, and the length measurement beam WXF ₃ reflected by the third reflection surface 54c is incident substantially perpendicularly on the reflection surface (the surface on the + X side). The angle is set.

The interferometer unit 58X ₂ irradiates the first reflecting surface 54a with a length measuring beam WX ₁ parallel to the X axis and the second reflecting surface 54b with a length measuring beam WX ₂ parallel to the X axis. The length measuring beam WX ₃ parallel to the X axis is irradiated to the third reflecting surface 54c.

Further, the interferometer unit 58X ₂ is provided with a fixed mirror 56b, and the length measurement beam WX ₃ reflected by the third reflection surface 54c is perpendicularly incident on the reflection surface (the surface on the + X side). It is set to an angle.

On the other hand, the side surface (side surface on the −Y side) of wafer table WTB facing interferometer unit 58Y is not shown, but the first region near the upper end, the second region near the lower end, and the first and second regions. It is divided into a third region sandwiched between the regions, and the first region and the second region are mirror-finished. The interferometer unit 58Y irradiates measurement beams WY ₁ and WY ₃ parallel to the Y axis to the reflection surface on the first region side, and measures parallel to the Y axis on the reflection surface on the second region side. Long beam WY ₂ is irradiated.

  Note that the entire surface of the −Y side surface may be mirror-finished, but it is desirable to mirror-finish the portions corresponding to the first region and the second region with high accuracy.

During the alignment, the measurement beams WXF ₁ and WXF ₂ of the interferometer unit 58X ₁ are used to measure the position of the wafer table WTB in the X-axis direction and the θy direction (rotation direction around the Y-axis). The position of wafer table WTB in the Z-axis direction is measured using measurement beams WXF _{1 to} WXF ₃ . Further, by using the measurement beams WY ₁ and WY ₂ of the interferometer unit 58Y, the position of the wafer table WTB in the Y-axis direction and the position of the θx direction (rotation direction around the X axis) can be measured. The position in the θz direction can be measured by the long beams WY ₁ and WY ₃ .

On the other hand, during exposure _, using the measurement beams WX ₁ and WX ₂ of the interferometer unit 58X ₂ , the position of the wafer table WTB in the X axis direction and the position in the θy direction (rotation direction around the Y axis) are determined. In addition to measurement, the position of wafer table WTB in the Z-axis direction is measured using measurement beams WXF _{1 to} WXF ₃ . Similarly to the alignment, the length measurement beams WY ₁ and WY ₂ of the interferometer unit 58Y are used to measure the position of the wafer table WTB in the Y-axis direction and the θx direction (rotation direction about the X axis). In addition, the position in the θz direction can be measured by the measurement beams WY ₁ and WY ₃ .

  Note that the position measuring method in the Z-axis direction of wafer table WTB is disclosed in Japanese Patent Application Laid-Open No. 2000-49066, and thus detailed description thereof is omitted.

Here, during both alignment and exposure, based on the difference between the measurement results of the measurement beams WXF ₁ and WXF ₂ (or WX ₁ and WX ₂ ) and the distance of each measurement beam in the Z-axis direction, Although the position of the wafer table WTB in the θy direction is measured, in the present embodiment, the first reflecting surface 54a and the second reflecting surface 54b are arranged at positions separated by sandwiching the third reflecting surface 54c. Therefore, it is possible to increase the distance in the Z-axis direction of each measurement beam without increasing the areas of the first and second reflecting surfaces. As a result, the first and second reflecting surfaces can be processed with high accuracy without incurring high costs, and the distance in the Z direction of the length measurement beam can be increased so that the position of the wafer table WTB in the θy direction can be obtained. Can be measured with high accuracy. Similarly, the first and second reflecting surfaces of the wafer table WTB used for measurement in the θx direction of the wafer table WTB are similarly separated from the first and second reflecting surfaces, so that mirror processing can be performed with high accuracy without incurring high costs. In addition, it is possible to measure the position of the wafer table WTB in the θx direction with high accuracy by increasing the distance in the Z direction of the length measurement beam.

  Next, the configuration of the self-weight canceller 150 of the present embodiment will be described in detail based on FIGS.

  As shown in the perspective view of FIG. 5, the self-weight canceller 150 of the present embodiment is in a state in which components of various structures are combined, and roughly divided, a fixing portion 90 fixed to the upper surface of the stage 31, A movable portion 190 that is movable in the Z direction with respect to the fixed portion 90 and that is partially connected to a fixed member 60 fixed to the lower surface of the wafer table WTB, and the movable portion 190 with respect to the fixed portion 90 And a drive mechanism VM for driving in the Z-axis direction.

  The fixing member 60 fixed to the wafer table WTB includes a disk portion 60c and a pair of L-shaped portions fixed to the ± Y side of the disk portion, as indicated by a dotted line in the exploded perspective view of FIG. 60a, 60b. Of these, the upper and lower surfaces of the disc portion 60c are set to have high flatness. Further, the upper end surfaces of the L-shaped portions 60a and 60b are fixed to the lower surface of the wafer table WTB (see FIG. 7).

  As shown in FIG. 6, the fixed portion 90 includes a substantially cubic frame member 92 and a piston portion 94 having a cylindrical portion 94 a at a part (Y-axis direction central portion). The piston portion 94 is fixed to the frame member 92 at the + Y side end portion and the −Y side end portion thereof.

  As shown in FIGS. 6 and 7, the movable portion 190 includes a pair of first clamping members 74 </ b> A and 74 </ b> B in a state where the disc portion 60 c of the fixed member 60 is sandwiched from above and below, and the pair of first clamping members. A pair of second clamping members 70A, 70B in a state where the members are sandwiched from above and below, and four spacer members 72a-72d for maintaining a predetermined distance between the pair of second clamping members 70A, 70B in the Z-axis direction; And a substantially cubic cylinder member 80 to which the lower surface of the lower second clamping member 70B is fixed.

  The first holding member 74A has a lower surface of a flat surface 174b and an upper surface of a spherical surface 174a. A disk portion of the fixing member 60 is formed by a gas static pressure bearing (first clearance forming mechanism) (not shown). A predetermined clearance 94A (see FIG. 7) is maintained with respect to the upper surface of 60c.

  The other first sandwiching member 74B is also vertically symmetrical but has the same configuration as the first sandwiching member 74A. The upper surface is a flat surface 274a and the lower surface is a spherical surface 274b. A predetermined clearance 94B (see FIG. 7) is maintained with respect to the lower surface of the disc portion 60c of the fixing member 60 by the bearing (first clearance forming mechanism).

  As shown in FIG. 7, the one second holding member 70A is formed with a concave surface 170a having a shape corresponding to the spherical surface 174a of the first holding member 74A on the lower surface side thereof. The predetermined clearance 96A is maintained with respect to the upper surface of the first clamping member 74A by the second clearance forming mechanism. The other second clamping member 70B is also symmetrical in the vertical direction, but is configured in the same manner as the one second clamping member 70B, and has a shape corresponding to the spherical surface 274b of the first clamping member 74B on the upper surface thereof. The concave surface 270a (see FIGS. 6 and 7) is formed. A predetermined clearance 96B (see FIG. 7) is maintained between the spherical surface 274b and the spherical concave surface 270a by a gas static pressure bearing (second clearance forming mechanism) (not shown).

  All of the spacer members 72a to 72d have the same Z-direction length, their upper ends are fixed to the four corners of the lower surface of the second clamping member 70A, and their lower ends are the four corners of the upper surface of the second clamping member 70B. It is fixed to the part.

  In the state where the first clamping members 74A and 74B and the second clamping members 70A and 70B are assembled to the fixing member 60, the pair of first clamping members 74A and 74B with respect to the fixing member 60 in the XY plane direction. Movement and rotation of the pair of second clamping members 70A and 70B relative to the pair of first clamping members 74A and 74B around the X axis and the Y axis are allowed in a non-contact state.

  The cylinder member 80 includes a substantially plate-like first plate member 82A and second plate member 82B, and four prismatic members 84 that maintain a predetermined distance between the plate members 82A and 82B. Yes.

  The first plate-like member 82A is formed with a concave portion 182a having a circular XY section from the upper surface side at the substantially central portion thereof, and a through hole 182b (see FIG. 7) is formed at the substantially central portion of the bottom surface of the concave portion 182a. Is formed. The upper side of the recess 182a is closed on the lower surface side of the second clamping member 70B, and the columnar portion 94a provided in the piston portion 94 of the fixing portion 90 is inserted into the through hole 182b. A predetermined clearance is formed between the outer peripheral surface of the cylindrical portion 94a and the inner wall of the through hole 182b by a gas static pressure bearing or the like, so that the gas in the recess 182a is prevented from leaking. Therefore, the space formed by the second clamping member 70B, the first plate-like member 82A, and the cylindrical portion 94a of the piston portion 94 is an airtight space AR. Gas (for example, air, nitrogen gas, etc.) is supplied into the airtight space AR via a gas supply pipe (not shown), a supply pipe line, and the like. Thereby, the airtight space AR becomes a positive pressure space. Hereinafter, the airtight space AR is also referred to as a positive pressure space AR. Note that a liquid or the like may be supplied in the positive pressure space AR instead of a gas, and a positive pressure may be generated by this liquid.

  The second plate-like member 82B is formed with an opening 282a having a circular XY cross section at substantially the center thereof. A part of a driving mechanism VM described later is inserted into the opening 282a (see FIGS. 5 and 7). The first plate member 82A and the second plate member 82B are connected by four prismatic members 84 with the piston member 94 sandwiched therebetween (see FIG. 7).

  As shown in FIG. 7, the drive mechanism VM moves in the Z-axis direction with respect to the stator 88A by electromagnetic interaction between the stator 88A fixed on the stage 31 and the stator 88A. It is comprised from the voice coil motor provided with the needle | mover 88B. A part of the mover 88B is connected to the bottom surface of the second plate-like member 82B, and the entire movable part 190 is driven in the Z-axis direction by the drive force of the drive mechanism VM.

  Here, in the assembled state as shown in FIG. 5, a predetermined clearance is formed by a static gas bearing (not shown) at a position where the four prismatic member 84 and the frame member 92 face each other. Thereby, the movable part 190 can move without generating friction with respect to the fixed part 90.

  According to the three self-weight cancellers 150 configured as described above, the wafer table WTB can be supported by the positive pressure in the positive pressure space AR, and the wafer table WTB is inclined in the XY plane and the XY plane. Even when moving by a minute amount, the clearances 94A, 94B, 96A, 96B are formed, so that the movement can be allowed. Further, it is possible to finely drive wafer table WTB in the Z-axis direction and in the θx and θy directions by drive mechanism VM. In the case of the present embodiment, each weight canceller 150 has a position where the driving force generated by the driving mechanism VM acts on the wafer table WTB and a position where the positive pressure generated in the positive pressure space AR acts on the wafer table WTB. It is configured to be positioned substantially coaxially with respect to the Z axis. Further, the driving force of the driving mechanism VM and the positive pressure (supporting force of the own weight of the wafer table WTB) by the positive pressure space AR act on the wafer table WTB in parallel with each other. However, the present invention is not limited to such a configuration.

In the exposure apparatus of the present embodiment, as in the prior art, the operation of projecting the pattern of the reticle R onto one shot area on the wafer W via the projection optical system PL under the illumination light IL, and the wafer stage WST The operation of moving the wafer W stepwise in the X-axis direction and the Y-axis direction is repeated in a step-and-repeat manner. In this case, the step movement is based on the measurement result of the wafer interferometer 58 (interferometer units 58X ₁ , 58X ₂ , 58Y), based on the stage drive system (X-axis linear motors 134X ₁ , 134X ₂ , Y-axis linear motor 134Y, X fine movement mechanism VX, Y fine movement mechanisms VY ₁ , VY ₂ , and drive mechanism VM of self-weight canceller 150).

  As described above in detail, the exposure apparatus according to the present embodiment includes the self-weight canceller 150. According to the self-weight canceller 150, the movable portion is movable in the direction of gravity with respect to the fixed portion 90 connected to the stage 31. Part 190 includes connection parts (first clamping members 74A and 74B) that are connected to wafer table WTB in a state where a part (fixing member 60) of wafer table WTB is sandwiched in a non-contact manner from both sides in the direction of gravity. Therefore, at least movement in the horizontal plane is allowed, and rigidity in the direction of gravity can be increased. Further, since at least a part of the own weight canceller 150 is not connected to wafer table WTB, it is possible to reduce the weight of the entire wafer table WTB (including a structure directly connected to wafer table WTB). .

  Thereby, wafer table WTB and movable portion 190 of self-weight canceller 150 are not in contact with each other, so that the weight of wafer table WTB as a whole (including the structure connected to wafer table) can be reduced, and wafer table WTB can be reduced. High acceleration can be achieved even when driving in a horizontal plane. Further, since the self-weight canceller 150 is connected in a state where a part (fixing member 60) of the wafer table WTB is sandwiched in a non-contact manner in the vertical direction, the stage 31 and the wafer table WTB are supported with high rigidity in the Z-axis direction. It becomes possible to do. As a result, the wafer table can be moved with high acceleration, and the throughput can be improved.

  Further, in the present embodiment, the cylinder member 80 is provided on the movable portion 190 side, the cylinder portion 94a is inserted into the cylinder member 80 on the fixed portion 90 side, and is relatively movable along the cylinder member 80. Since the piston member 94 is provided, the wafer table WTB can be supported by the positive pressure of the gas in the airtight space AR that urges the cylindrical portion 94a of the piston member 94 in the direction of gravity. Therefore, wafer table WTB can be supported with low rigidity, and it is not necessary to always generate a driving force in the Z-axis direction by drive mechanism VM to support wafer table WTB. It is possible to suppress the occurrence of fluctuations in the vicinity atmosphere, and hence the reduction in exposure accuracy.

  In the present embodiment, the positive pressure in the positive pressure space AR is used to support the wafer table WTB with respect to the stage 31, so that the vibration from the floor surface F is transmitted in the positive pressure space AR. Can be absorbed. Thereby, it is not necessary to provide an anti-vibration mechanism between the stage surface plate BS and the floor surface F, and high-precision exposure can be realized at low cost.

  In the present embodiment, the pair of first clamping members 74A and 74B and the first clamping members 74A and 74B for clamping a part of the wafer table WTB (fixing member 60) in a non-contact manner from both sides in the vertical direction are arranged in the vertical direction. The pair of second clamping members 70A and 70B sandwiched between the first and second clamping members 74A and 74B and the second clamping members 70A and 70B are spherical surfaces. Even when it is intended to incline in the direction inclined to the horizontal plane, the relative positional relationship between the first holding members 74A and 74B and the second holding members 70A and 70B is changed, so that the inclination of the wafer table WTB is increased. Can be tolerated. Thereby, wafer table WTB can be finely driven in the θx and θy directions.

  In the present embodiment, a predetermined clearance is provided between the first sandwiching members 74A and 74B and the fixing member 60 and between the second sandwiching members 70A and 70B and the first sandwiching members 74A and 74B by a static gas bearing. Thus, the members can be maintained in a non-contact manner, and the movement of the wafer table WTB in the horizontal plane and in the θx and θy directions can be allowed without being affected by friction or the like.

  Further, in the exposure apparatus 10 of the present embodiment, in the stage apparatus 50, the first, second, and third areas are provided along the Z-axis direction on the side surface of the wafer table WTB, and the first and second areas among them are provided. Since the first and second reflection surfaces 54a and 54b reflect the measurement beam from the wafer interferometer 58, the first and second reflection surfaces are measured when the rotation of the wafer table WTB in the θy direction is measured. By irradiating the measurement beams to 54a and 54b, the distance of the measurement beams in the Z-axis direction can be increased. As a result, the distance in the Z direction of the measurement beam can be increased without increasing the total area of the reflecting surface, so that high-precision mirror processing can be performed without incurring high costs, and high-precision measurement can be performed. It is possible to realize. Therefore, it is possible to accurately measure the rotation of wafer table WTB in the θy direction.

Further, in the exposure apparatus 10 of the present embodiment, in the stage apparatus 50, grooves 41a and 41b having a predetermined depth are formed in at least a part of the outside of the suction fixing region that sucks the wafer holder 25 of the wafer table WTB. Since the driving force by the X fine movement mechanism VX and the Y fine movement mechanisms VY ₁ , VY ₂ spreads over the wafer table in a state of wrapping around the grooves 41a, 41b, the influence can be mitigated. . Thereby, highly accurate exposure can be realized.

  In the above embodiment, the piston member is provided on the fixed portion 90 side of the self-weight canceller 150 and the cylinder member is provided on the movable portion 190 side. However, the present invention is not limited to this, and the fixed portion 90 side is provided. It is good also as providing a cylinder member in this and providing a piston member in the movable part 190 side.

  In the above-described embodiment, the inside of the airtight space AR of the self-weight canceller 150 is configured to be positive pressure to support the self-weight of the wafer table WTB. However, the present invention is not limited to this. What is necessary is just to comprise so that the force of the + Z direction which supports the wafer table WTB with the pressure in the airtight space AR may generate | occur | produce. For example, the inside of the airtight space AR is set to a negative pressure (vacuum), and a force in the + Z direction that supports the wafer table WTB is generated by a differential pressure between the airtight space AR and the surrounding atmospheric pressure (for example, atmospheric pressure). You may do it. A configuration for generating a force to support an object using a vacuum is disclosed in, for example, Japanese Patent Application Laid-Open No. 60-78125. When the influence of heat generation is small, the weight of wafer table WTB may be supported by the driving force generated by drive mechanism VM.

  In the embodiment described above, the case where the first clamping members 74A and 74B and the second clamping members 70A and 70B face each other is a spherical surface. However, the present invention is not limited to this, and an aspherical surface may be used. . In addition, portions where the upper and lower surfaces of the disk portion 60c of the fixing member 60 and the first clamping members 74A and 74B are opposed may be spherical or aspherical. Furthermore, in the above embodiment, the upper surface of the first clamping member 74A and the lower surface of the first clamping member 74B are set to be convex, and the lower surface of the second clamping member 70A and the upper surface of the second clamping member 70B are set to be concave. However, the present invention is not limited to this, and the first clamping members 74A and 74B may be set in a concave shape, and the second clamping members 70A and 70B may be set in a convex shape.

  In the above embodiment, a static gas bearing is provided between the first clamping members 74A and 74B and the fixing member 60 and between the second clamping members 70A and 70B to form a predetermined clearance. However, the present invention is not limited to this. For example, a gas that generates a positive pressure for supporting the weight of wafer table WTB supplied to airtight space AR and a gas that is supplied between the members to form a predetermined clearance may be made common. . In that case, each member is provided with a conduit through which the gas communicated with the airtight space AR can flow, and a predetermined clearance is obtained by utilizing the static pressure of the gas ejected into the gap between the members via this conduit. Can be formed.

  Further, although gas is used to form a predetermined clearance, a bearing using magnetic force may be used. Further, a type of bearing that generates a preload by vacuum or magnetic force may be used.

  In the above embodiment, if the fixing member 60 and the first clamping members 74A and 74B are not in contact, the first clamping members 74A and 74B and the second clamping members 70A and 70B are not in contact. It is not necessary.

  In the above-described embodiment, the case where the fixing member 60 is fixed to the lower surface of the wafer table WTB has been described. However, the fixing member 60 is not limited to this, and may be fixed to the side surface of the wafer table WTB. In this case, the fixing member 60 may be a plate member.

  In the above embodiment, the case where the self-weight canceller 150 is provided with the fine movement mechanism VM has been described. It may be provided.

  In the above embodiment, the case where the fixing portion 90 of the self-weight canceller 150 is fixed to the upper surface of the stage 31 has been described.

  In the above embodiment, the case where the self-weight canceller 150 is provided on the wafer stage WST has been described. However, the present invention is not limited to this, and may be provided on the reticle stage RST side. In addition to the exposure apparatus, various apparatuses can be used as long as the second object is supported with respect to the first object (for example, a part of a vibration isolator for supporting the optical system of the exposure apparatus). It is possible to apply to.

  In the above-described embodiment, the case where the grooves 41a and 41b are formed on the wafer table WTB at positions that do not mechanically interfere with the wafer holder 25 has been described. However, the present invention is not limited to this, and the wafer holder 25 may be narrowed so that the grooves 41a and 41b are positioned below the wafer holder 25. By doing so, it is possible to reduce the size of wafer table WTB.

In the above-described embodiment, far ultraviolet light such as KrF excimer laser light, illumination light IL, vacuum ultraviolet light such as F ₂ laser and ArF excimer laser, or ultraviolet bright line (g-line, However, the present invention is not limited to this, and other vacuum ultraviolet light such as Ar ₂ laser light (wavelength 126 nm) may be used. Further, for example, not only laser light output from each of the above light sources as vacuum ultraviolet light, but also single wavelength laser light in the infrared region or visible region oscillated from a DFB semiconductor laser or fiber laser, for example, erbium (Er) A harmonic that is amplified by a fiber amplifier doped with erbium and ytterbium (Yb) and wavelength-converted into ultraviolet light using a nonlinear optical crystal may be used.

  Further, an exposure apparatus that uses EUV light, X-rays, or charged particle beams such as an electron beam or an ion beam as illumination light IL, a projection system that does not use a projection optical system, such as a proximity type exposure apparatus, a mirror projection aligner, and The present invention may also be applied to an immersion type exposure apparatus disclosed in International Publication WO99 / 49504 and the like in which a liquid is filled between the projection optical system PL and the wafer.

  In the above embodiment, the case where the present invention is applied to the step-and-repeat reduction projection exposure apparatus has been described. However, the scope of the present invention is of course not limited thereto. That is, the present invention can be suitably applied to a scanning exposure apparatus such as a step-and-scan method.

  An illumination optical system and projection optical system composed of a plurality of lenses are incorporated into the exposure apparatus body for optical adjustment, and a reticle stage and wafer stage made up of a number of mechanical parts are attached to the exposure apparatus body to provide wiring and piping. , And further performing general adjustment (electrical adjustment, operation check, etc.), the exposure apparatus of the above embodiment can be manufactured. The exposure apparatus is preferably manufactured in a clean room where the temperature, cleanliness, etc. are controlled.

  The present invention is not limited to an exposure apparatus for manufacturing a semiconductor, but is used for manufacturing a display including a liquid crystal display element. An exposure apparatus for transferring a device pattern onto a glass plate and a device used for manufacturing a thin film magnetic head. The present invention can also be applied to an exposure apparatus that transfers a pattern onto a ceramic wafer, and an exposure apparatus that is used for manufacturing an imaging device (CCD or the like), micromachine, organic EL, DNA chip, and the like. Further, in order to manufacture reticles or masks used in not only microdevices such as semiconductor elements but also light exposure apparatuses, EUV exposure apparatuses, X-ray exposure apparatuses, electron beam exposure apparatuses, etc., glass substrates or silicon wafers, etc. The present invention can also be applied to an exposure apparatus that transfers a circuit pattern. Here, in an exposure apparatus using DUV (far ultraviolet) light, VUV (vacuum ultraviolet) light, or the like, a transmission type reticle is generally used. As a reticle substrate, quartz glass, fluorine-doped quartz glass, meteorite, Magnesium fluoride or quartz is used. Further, in a proximity type X-ray exposure apparatus or an electron beam exposure apparatus, a transmission mask (stencil mask, membrane mask) is used, and a silicon wafer or the like is used as a mask substrate.

  The present invention includes, for example, JP-A-10-163099, JP-A-10-214783 and US Pat. No. 6,400,441 corresponding thereto, JP 2000-505958A and US corresponding thereto. The present invention can also be applied to the twin stage type exposure apparatus described in Japanese Patent No. 5,969,441 and US Pat. No. 6,262,796.

  In addition, as disclosed in JP-A-11-135400, the present invention includes an exposure stage that can move while holding a substrate to be processed such as a wafer, and a measurement stage that includes various measurement members and sensors. The present invention can also be applied to a provided exposure apparatus.

  In the above-described embodiment, a light-transmitting mask in which a predetermined light-shielding pattern (or phase pattern / dimming pattern) is formed on a light-transmitting substrate, or a predetermined reflecting pattern on a light-reflecting substrate. Although the formed light reflection type mask is used, it is not limited to them. For example, instead of such a mask, an electronic mask (which is a kind of optical system) that forms a transmission pattern, a reflection pattern, or a light emission pattern based on electronic data of a pattern to be exposed may be used. Such an electronic mask is disclosed in, for example, US Pat. No. 6,778,257. Note that the above-described electronic mask is a concept including both a non-light-emitting image display element and a self-light-emitting image display element.

  Further, for example, the present invention can also be applied to an exposure apparatus that exposes a substrate with interference fringes caused by interference of a plurality of light beams, which is called two-beam interference exposure. Such an exposure method and exposure apparatus are disclosed in, for example, WO 01/35168.

  Furthermore, the present invention is also applicable to an immersion exposure apparatus that irradiates a substrate with exposure light through a liquid. As such an immersion exposure apparatus, for example, a system disclosed in International Publication No. 2004/053958 is known as a system for locally filling a space between a projection optical system and a substrate. The present invention also relates to an immersion exposure apparatus that moves a stage holding a substrate to be exposed in a liquid tank, and an immersion exposure apparatus that forms a liquid layer of a predetermined thickness on the stage and holds the substrate therein. Is applicable. For example, JP-A-6-124873, JP-A-10-303114, and US Pat. No. 5,825,043 disclose their configurations. Further, as disclosed in International Publication No. 2004/019128, the present invention is applied to an immersion exposure apparatus that fills the optical path space on the exit side and the entrance side of the terminal optical member of the projection optical system with a liquid. Also good.

  A semiconductor device includes a step of performing functional / performance design of a device, a step of manufacturing a reticle based on the design step, a step of manufacturing a wafer from a silicon material, and a reticle by the above-described method using the exposure apparatus of the above-described embodiment. This pattern is manufactured through a step of transferring the pattern to a wafer, a device assembly step (including a dicing process, a bonding process, and a packaging process), an inspection step, and the like.

  As described above, the support device of the present invention is suitable for supporting the second object with respect to the first object. The stage apparatus of the present invention is suitable for driving the stage in at least a two-dimensional plane. The exposure apparatus of the present invention is suitable for exposing a substrate.

It is the schematic which shows the exposure apparatus which concerns on one Embodiment. It is a schematic plan view which shows the stage apparatus of FIG. 3A to 3D are views for explaining the arrangement of grooves formed in the wafer table and the operation thereof. It is a figure for demonstrating the structure of a wafer interferometer system, and the reflective surface provided in the side surface by the side of -X of a wafer table. It is a perspective view which shows a self-weight canceller. It is a disassembled perspective view of the self-weight canceller of FIG. It is sectional drawing of the self-weight canceller of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus, 25 ... Wafer holder (substrate holding member), 31 ... Stage (1st object), 41a, 41b ... Groove, 50 ... Stage apparatus, 54A ... 1st area | region (1st reflective surface), 54B ... 2nd Area (second reflecting surface), 54C ... third area (third reflecting surface), 58 ... wafer interferometer system (measuring device), 70A, 70B ... second clamping member (part of connecting portion), 74A, 74B ... first clamping member (part of connecting part), 80 ... cylinder member (cylinder part), 90 ... fixed part, 94 ... piston part, 150 ... self-weight canceller (support device), 190 ... movable part, VM ... drive mechanism (Fine movement mechanism), VX ... X fine movement mechanism (drive mechanism), VY ₁ , VY ₂ ... Y fine movement mechanism, W ... wafer (substrate), WTB ... wafer table (second object, table).

Claims (10)

A support device for supporting a second object with respect to a first object,
A fixed part connected to the first object;
A movable part movable in the direction of gravity with respect to the fixed part;
Said movable portion, a portion of the second object viewed sandwiched in a non-contact from both sides in the direction of gravity, in a state in which movement is allowed within the plane perpendicular to the direction of gravity with respect to the portion of the second object A support device comprising a connection portion connected to the second object. A cylinder part connected to one of the movable part and the fixed part and a cylinder part inserted into the cylinder part connected to the other of the movable part and the fixed part and movable relative to the cylinder part. A further piston part,
2. The support device according to claim 1 , wherein the weight of the second object is supported on the first object by a pressure inside the cylinder part that urges the piston part in a gravitational direction. The connecting portion is
A pair of first clamping members for clamping a part of the second object from the one side and the other side in the gravitational direction without contact;
A pair of second clamping members that clamp the first clamping member from one side and the other side in the gravity direction;
The support device according to claim 1 or 2 , wherein a portion where the first clamping member and the second clamping member face each other is a spherical surface or an aspherical surface. The support device according to claim 3 , further comprising a first clearance forming mechanism that forms a predetermined clearance between the first clamping member and a part of the second object. The support device according to claim 3 , further comprising a second clearance forming mechanism that forms a predetermined clearance between the second clamping member and the first clamping member. A supporting installation as claimed in any one of claims 1 to 5, further comprising a fine movement mechanism for finely driving the gravity direction the movable portion relative to said stationary portion. A stage movable in a two-dimensional plane;
A stage device comprising: a support device according to any one of claims 1 to 6 that supports a table that holds a substrate with respect to the stage. The stage device according to claim 7 , wherein the support devices are provided at three locations that are not in a straight line. The stage apparatus according to claim 7 or 8 , further comprising a drive mechanism that finely drives the second object with respect to the first object in a two-dimensional plane. A stage apparatus according to any one of claims 7 to 9 , comprising:
An exposure apparatus that exposes a substrate held on the stage.

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