JP2006165363A - Support apparatus, stage apparatus, and exposure apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology of eliminating the need for an actuator for always generating a supporting force to support the self-weight of an object so as to obviate defects caused by heat generated from the actuator. <P>SOLUTION: A support apparatus 52a is arranged in a vacuum atmosphere. A gas chamber 109 is formed by a cylindrical member 170 provided with an inner circumferential face extended in the vertical direction and the upper end of a slider 70 movable along the inner circumferential face in the support apparatus 52a. The gas chamber 109 is opened to air via pipelines (118, 128). The lower end of the slider 70 is coupled with a differential static pressure bearing mechanism 70b including a permanent magnet 72. The object 30 is supported by a slider mechanism 70b via a prescribed clearance by means of a balance between the static pressure of a gas ejected from the static pressure bearing mechanism 70b and the prepressure of the permanent magnet 72. The self-weight of the object is supported by a force produced by a differential pressure (pressure difference) between the pressure of the gas in the gas chamber and the pressure of the vacuum atmosphere. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a support apparatus, a stage apparatus, and an exposure apparatus, and more particularly, to a support apparatus that is used in a vacuum atmosphere and supports an object, a stage apparatus including the support apparatus, and an exposure apparatus including the stage apparatus.

  Conventionally, in a lithography process for manufacturing a semiconductor element, a liquid crystal display element, and the like, a resist or the like is applied to a pattern formed on a mask or a reticle (hereinafter collectively referred to as “reticle”) via a projection optical system. A step-and-repeat reduction projection exposure apparatus (so-called “stepper”) for transferring onto a substrate such as a wafer or a glass plate (hereinafter also referred to as a wafer as appropriate), or a step-and-scan scanning exposure apparatus ( Scanners) are mainly used.

  These exposure apparatuses have been required to further improve the resolution of the projection optical system due to the high integration of semiconductor elements and the accompanying fine pattern. For this reason, the wavelength of exposure light has been shortened year by year, and recently, an SOR (Synchrotron Orbital Radiation) ring or a laser plasma light source that generates extreme ultraviolet light (EUV (Extreme Ultraviolet) light) having a wavelength of 100 nm or less is used. Development of an EUV exposure apparatus (EUVL) used as an exposure light source has been performed.

  In an EUV exposure apparatus, since there is no optical material that can transmit EUV light at this time, the illumination optical system and the projection optical system are all-reflective optical systems composed of only reflective optical members (reflective optical elements). A reflective reticle is also used as the reticle. In addition, since EUV light is absorbed by almost all substances, the optical path space of the EUV light needs to be set to a predetermined high vacuum state, and the main body of the EUV exposure apparatus is usually installed in a vacuum chamber.

  In recent years, with the increase in size of reticles and wafers, mainly from the viewpoint of improving throughput, scanning exposure apparatuses capable of exposing a large area at a time compared with a batch exposure apparatus have become mainstream. In the scanning exposure apparatus, as a means for controlling the position of the reticle with higher accuracy, a reticle coarse movement stage that moves with a long stroke in the scanning direction, and the reticle coarse movement stage that can be finely driven with respect to the reticle coarse movement stage are held. A relatively fine and fine movement stage having a fine movement stage is used in a relatively large number.

  When a coarse / fine movement stage is used in an EUV exposure apparatus, a reflective reticle is used, so that the fine movement stage holding the reticle is suspended and non-contacting from the viewpoint of vibration reduction. It is necessary to support. Therefore, it is necessary to always generate a force for supporting the self-weight of the reticle fine movement stage by an actuator such as a voice coil motor. Recently, however, there is a concern that the heat generated by the actuator may affect the exposure accuracy. .

  Similar problems may occur when a table holding a wafer is supported with respect to the stage via a non-contact bearing.

  The present invention has been made under the circumstances described above. From the first viewpoint, the present invention is a support device that is used in a vacuum atmosphere and supports an object (30). A hydrostatic bearing mechanism (70b); a cylindrical member (170) having an inner peripheral surface extending in a vertical direction; and the first hydrostatic bearing mechanism coupled to one end and moving along the inner peripheral surface A possible slider (70); a gas chamber (109) formed by the tubular member and the other end of the slider; so as to support the dead weight of the object by a differential pressure with the vacuum atmosphere; And a supply device (108, 118, 128) for supplying a gas having a predetermined pressure to the gas chamber.

  In this specification, the cylindrical member may be a member having a cylindrical portion extending in the vertical direction and having the inner wall surface as the inner peripheral surface, or an opening portion (a through hole) extending in the vertical direction. Or a member whose one end may be closed), and the inner wall surface of the opening is the inner circumferential surface. In short, any member may be used as long as the inner peripheral surface for guiding the slider in the vertical direction is partially formed. The slider is shaped according to the cylindrical member and is movable along the inner peripheral surface. The other end portion communicates with the inner peripheral surface of the cylindrical member together with the gas chamber. Anything can be used.

  According to this, the weight of the object is supported by the force generated by the differential pressure (pressure difference) between the gas in the gas chamber and the vacuum atmosphere. Therefore, an actuator for constantly generating a supporting force for supporting the weight of the object is unnecessary, and various inconveniences due to the heat generated by the actuator do not become a problem. Further, the object can be held in a non-contact manner by the first hydrostatic bearing mechanism. Further, since the slider provided with the first hydrostatic bearing mechanism is movable along the inner peripheral surface provided in the cylindrical member and extending in the vertical direction, the object is allowed to move at least in the vertical direction. ing.

  From a second viewpoint, the present invention is a stage apparatus including a stage (RST) movable in a two-dimensional plane having the support apparatus of the present invention.

  According to this, since the stage having the support device that solves the problem of heat generation of the actuator for constantly generating the support force for supporting the weight of the object is provided, the thermal effect applied to the members and atmosphere around the stage Can be reduced. For example, when the position information of the stage is measured by an optical measurement device, the influence of heat on the measurement accuracy can be reduced, and the position controllability of the stage can be improved.

  According to a third aspect of the present invention, in the exposure apparatus that drives the stage apparatus (12) to expose the substrate (W) and forms a pattern on the substrate, the stage apparatus is the stage apparatus of the present invention. An exposure apparatus characterized by that.

  According to this, a stage apparatus capable of improving the position controllability of the stage is driven to expose the substrate, and a pattern is formed on the substrate. As a result, a highly accurate pattern can be formed on the substrate. It becomes.

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

  FIG. 1 schematically shows the overall configuration of an exposure apparatus 10 according to an embodiment. In FIG. 1, the projection unit PU and the wafer stage chamber 45 constituting the exposure apparatus 10 are broken and shown in a sectional view to show the internal structure.

  In this exposure apparatus 10, a projection unit PU having a projection optical system for projecting a reflected light beam from a reticle R as a reflective mask vertically onto a wafer W as a substrate is employed. The projection direction of the illumination light from the projection optical system onto the wafer W is referred to as the optical axis direction of the projection optical system, and this optical axis direction is the Z-axis direction, and the horizontal direction in FIG. Is defined as the Y-axis direction, and the direction orthogonal to the paper surface is defined as the X-axis direction.

  The exposure apparatus 10 projects a partial image of a circuit pattern (hereinafter abbreviated as “reticle pattern”) formed on the reticle R onto the wafer W via the projection optical system in the projection unit PU. The reticle R and the wafer W are scanned in a one-dimensional direction (Y-axis direction) relative to the projection unit PU, so that the reticle pattern is applied to each of a plurality of shot areas on the wafer W in a step-and-scan manner. Transcript.

  The exposure apparatus 10 includes an illumination unit 10A that illuminates the reticle R with illumination light (EUV light) EL, and an exposure apparatus main body 10B that is partially connected to the illumination unit 10A.

  Although the illumination unit 10A is shown as a simple block in FIG. 1 for convenience of illustration, actually, illumination light (EUV light) in a soft X-ray region, for example, illumination light (EUV light) EL having a wavelength of 11 nm is used. An exposure light source and illumination optical system (not shown) composed of an emitting SOR (Synchrotron Orbital Radiation) ring, an illumination system composed of a beam line (not shown) connecting them, and an illumination system chamber 40 for housing the illumination system. I have.

  The illumination system chamber 40 is provided on an illumination system holding frame 56 composed of a plurality of support members 53 provided on the floor surface F and a support surface plate 50 supported horizontally by the support members 53. is set up. The illumination system chamber 40 is configured to be highly airtight so that a high vacuum state such as a space defined by the illumination system chamber 40 and the support surface plate 50 can be maintained.

  The illumination optical system includes, for example, a mirror system, a fly-eye mirror, a mirror unit (for example, a reflection mirror composed of a plurality of toroidal aspheric oblique incidence mirrors), and the like. Among the components of the illumination optical system, the mirror unit constitutes the exit end of the illumination system, and a part of the mirror unit protrudes from the opening of the illumination system chamber 40 that covers a predetermined space above the support member 53. Yes. This illumination optical system sequentially reflects the illumination light EL emitted from the light source, and finally reflects the pattern surface of the reticle R at a predetermined incident angle, for example, about 50 [mrad] (the lower surface in FIG. 1 (the surface on the −Z side). )).

  As shown in FIG. 1, the exposure apparatus main body 10B includes a reticle stage RST that includes a reticle stage RST that holds a reticle R, a reticle stage chamber that houses the reticle stage RST and its drive system, and the like. Projection unit PU including a projection optical system that projects illumination light EL reflected by the R pattern surface onto an exposed surface of wafer W, wafer stage WST on which wafer W is placed, and first column that holds projection unit PU 31, a second column 37 that supports the reticle stage device 12 on a lens barrel surface plate (main frame) 35 that constitutes the first column 31, and a wafer stage chamber 45 that accommodates the wafer stage WST and the like. Yes.

  As the reticle R, a reflective reticle is used in correspondence with the illumination light EL being EUV light having a wavelength of 11 nm. The reticle R is held on the reticle stage RST with its pattern surface being the lower surface. The reticle R is made of a thin plate such as a silicon wafer, quartz, or low expansion glass, and a reflective film that reflects EUV light is formed on the surface (pattern surface) on the −Z side. This reflective film is a multilayer film in which about 50 pairs of molybdenum Mo and beryllium Be films are alternately laminated with a period of about 5.5 nm. This multilayer film has a reflectance of about 70% for EUV light having a wavelength of 11 nm.

  On the multilayer film formed on the pattern surface of the reticle R, for example, nickel Ni or aluminum Al is applied on one surface as an absorption layer, and the absorption layer is patterned to form a circuit pattern.

  Illumination light (EUV light) EL that hits the portion of the reticle R where the absorption layer remains is absorbed by the absorption layer, and illumination that hits the reflection film in the portion where the absorption layer has been removed (portion from which the absorption layer has been removed) The light EL is reflected by the reflection film, and as a result, the illumination light EL including circuit pattern information travels toward the projection unit PU as reflected light from the pattern surface of the reticle R.

  The second column 37 is supported by a plurality of, for example, three or four columns 39 provided on the upper surface of the first column 31 and the plurality of columns 39, and constitutes a top plate of the second column 37. The lower plate 19 is included. The detailed configuration of the reticle stage device 12 supported by the second column 37 will be described later.

  The first column 31 includes a plurality of (for example, three or four) support members 23 provided on the floor surface F, and a plurality of vibration isolation units 25 provided respectively on the support members 23. And the lens barrel surface plate 35 that is supported substantially horizontally on the floor surface F by the support member 23 and the vibration isolation unit 25.

  Each anti-vibration unit 25 includes an air mount and a voice coil motor, which are arranged in series (or in parallel) on the support member 23 and can adjust the internal pressure. The air mount of each vibration isolation unit 25 is adapted to insulate minute vibrations from the floor surface F transmitted to the lens barrel surface plate 35 via the floor surface F and the support member 23.

  The lens barrel surface plate 35 is made of a casting or the like, and is formed in a central portion of the first opening 35a that is circular in a plan view (viewed from above) and is located at a predetermined distance in the + X direction from the first opening 35a. And a second opening (not shown).

  The above-described projection unit PU is inserted into the first opening 35a of the lens barrel base plate 35 from above, and three anti-vibration units (one anti-vibration unit in FIG. 1) are provided on the lens barrel base plate 35. 29), the flange portion FLG of the projection unit PU is supported at three points from below. As each image stabilization unit 29, the thing of the structure similar to the above-mentioned image stabilization unit 25 is used.

  An alignment detection system (not shown) is inserted from above into the second opening of the lens barrel surface plate 35 and is fixed to the lens barrel surface plate 35 via a flange provided on the outer periphery. As this alignment detection system, FIA (Field Image Alignment) which irradiates an alignment mark (or an aerial image measuring device FM described later) on the wafer W with broadband light, receives the reflected light, and performs mark detection by image processing. LIA (Laser Interferometric) which irradiates the diffraction grating-shaped alignment mark on the wafer W from two directions, interferes with the two generated diffracted lights, and detects the position information of the alignment mark from the phase. (Alignment) type alignment sensor, LSA (Laser Step Alignment) type alignment sensor or AFM (AFM) that irradiates an alignment mark on the wafer W with laser light and measures the mark position using the intensity of diffracted and scattered light. Various types such as a scanning probe microscope such as an atomic force microscope can be used. wear.

  The projection unit PU includes a lens barrel 14, a second mirror M 2, a fourth mirror M 4, a second mirror M 4, and a fourth mirror M 4 arranged in order from top to bottom in a predetermined positional relationship as shown in FIG. A projection optical system including a total of four mirrors (reflection optical elements), that is, three mirrors M3 and a first mirror M1. This projection optical system has a numerical aperture (NA) of 0.1, for example, and a projection magnification of 1/4. The fourth mirror M4 has an opening as shown in FIG.

  Further, as can be seen from FIG. 1, the lens barrel 14 has an opening 59a on the -Y side of the peripheral wall, and the above-mentioned mirror unit 1 is configured inside the lens barrel 14 through the opening 59a. Two reflecting mirrors Mc are inserted. Further, as shown in FIG. 1, openings 59b and 59c serving as passages for the illumination light EL are formed in the upper wall (ceiling wall) and the bottom wall of the lens barrel 14.

  In addition, between the lens barrel 14 and the illumination system chamber 40, the telescopically connecting the lens barrel 14 and the illumination system chamber 40 to the peripheral portion of the opening 59a and the opening on the illumination system chamber 40 side facing the opening 59a. A bellows 47 is provided. The bellows 47 isolates the internal space of the lens barrel 14 and the internal space of the illumination system chamber 40 in an almost airtight state from the outside, and transmits vibration between the lens barrel 14 and the illumination system chamber 40. Is suppressed.

  According to the projection unit PU configured as described above, after the illumination light EL described above reaches the reflection surface of the reflection mirror Mc, and is reflected and collected by the reflection surface, as shown in FIG. Then, it enters the pattern surface (lower surface) of the reticle R through the opening 59b of the lens barrel 14 at a predetermined incident angle, for example, 50 (mrad). As a result, the pattern surface of the reticle R is illuminated by the illumination light EL having the arcuate slit shape.

  Then, the illumination light EL including information on the reticle pattern reflected by the pattern surface of the reticle R enters the lens barrel 14 through the opening 59b and reaches the first mirror M1. The illumination light EL reflected by the reflecting surface of the first mirror M1 enters the reflecting surface of the second mirror M2 through the opening of the fourth mirror M4, is reflected by the reflecting surface, and passes through the opening of the fourth mirror M4. Through the reflecting surface of the third mirror M3. The illumination light EL reflected by the reflecting surface of the third mirror M3 is reflected by the reflecting surface of the fourth mirror M4, and the direction of the principal ray is deflected vertically downward. The illumination light EL is projected onto the wafer W. Thereby, a reduced image of the reticle pattern is formed on the wafer W.

  Further, wafer focus sensors (112a, 112b) are integrally attached to the lens barrel 14 of the projection unit PU via a holding unit (not shown). The wafer focus sensors (112a, 112b) include an irradiation system 112a for irradiating a test surface (the surface of the wafer W) with a plurality of light beams from a direction inclined by a predetermined angle with respect to the optical axis of the projection optical system, and each light beam. An oblique incidence type multipoint focal position detection system including a light receiving system 112b having a plurality of light receiving elements that individually receive reflected light from the surface to be measured is used. The wafer focus sensor (112a, 112b) measures the position and the amount of tilt in the Z-axis direction of the surface of the wafer W with reference to the lens barrel 14 of the projection unit PU. A multi-point focal position detection system having the same configuration as the wafer focus sensors (112a, 112b) is disclosed in detail in, for example, Japanese Patent Laid-Open No. 6-283403 (corresponding US Pat. No. 5,448,332). .

  Wafer stage WST is levitated and supported on wafer stage base 33 by a wafer stage driving unit (not shown) made of, for example, a magnetic levitation type two-dimensional linear actuator. Wafer stage WST is driven by the wafer stage drive unit in the X-axis direction and Y-axis direction with a predetermined stroke (the stroke is, for example, 300 to 400 mm), and is also minute in the θz direction (rotation direction about the Z-axis). The amount is driven. Wafer stage WST is configured to be able to be driven by a minute amount in the Z-axis direction and the tilt direction with respect to the XY plane by a wafer stage driving unit.

  An electrostatic chuck type wafer holder (not shown) is placed on the upper surface of wafer stage WST, and wafer W is attracted and held by the wafer holder. The position of wafer stage WST is always detected by a wafer laser interferometer (hereinafter referred to as “wafer interferometer”) 82W arranged outside, for example, with a resolution of about 0.5 to 1 nm. In practice, an interferometer having a length measuring axis in the X-axis direction and an interferometer having a length measuring axis in the Y-axis direction are provided. In FIG. 1, these are typically shown as a wafer interferometer 82W. Has been. These interferometers are composed of multi-axis interferometers having a plurality of measurement axes, and in addition to the X and Y positions of wafer stage WST, rotation (yawing (θz rotation that is rotation around the Z axis)), pitching (X axis) Rotation around (θx rotation) and rolling (θy rotation around Y axis)) can also be measured.

  The measurement values of wafer interferometer 82W and wafer focus sensors (112a, 112b) are supplied to a main control device (not shown), and the main control device controls the wafer stage driving unit, and the position of wafer stage WST in the six-dimensional direction. In addition, posture control is performed.

  To measure the relative positional relationship (so-called baseline measurement) between the position where the pattern formed on the reticle R is projected onto the wafer W surface and the above-described alignment detection system at one end of the upper surface of wafer stage WST. An aerial image measuring instrument FM is provided. This aerial image measuring instrument FM corresponds to a reference mark plate of a conventional DUV exposure apparatus.

  The wafer stage chamber 45 has a substantially box-like shape with an open upper surface, and is fixed to the lower surface of the lens barrel surface plate 35. The wafer stage chamber 45 is configured to maintain a high vacuum state in a closed space defined by the wafer stage chamber 45 and the lens barrel surface plate 35.

  Next, the reticle stage device 12 and its neighboring components will be described with reference to FIGS. FIG. 2 is a longitudinal sectional view of the reticle stage device 12 taken along a plane orthogonal to the Y-axis direction that is the scanning direction. FIG. 3 is a plan view showing components of the reticle stage device 12 accommodated in the reticle stage chamber RC described above.

  As shown in FIG. 2, the reticle stage device 12 includes a reticle stage chamber RC, a reticle stage RST accommodated in the reticle stage chamber RC, its drive system, and a frame-like member that functions as a counter mass. 20 (see FIG. 3).

  As shown in FIG. 2, the reticle stage chamber RC has a lower plate 19 constituting the top plate of the second column 37 described above, and an XZ cross section fixed on the lower plate 19 has an inner opening. A U-shaped side wall member 18 formed of an annular member having a rectangular frame shape in plan view (viewed from above), and an upper plate 16 fixed to the upper portion of the side wall member 18 are provided.

An opening 19a is formed in the central portion of the lower plate 19, and the peripheral portion of the opening 19a of the lower plate 19 and the upper end surface of the projection optical system PL are connected by a bellows 21, thereby the reticle. External gas is prevented from entering the internal space of the stage chamber RC and the internal space of the lens barrel 14. As can be seen from the above description, in the present embodiment, the interiors of the reticle stage chamber RC, bellows 21, the projection unit PU lens barrel 14, bellows 47, illumination system chamber 40, and wafer stage chamber 45 communicate with each other. An airtight space is formed. Here, as an example, it is assumed that the inside of the airtight space is maintained in a high vacuum state of about 10 ⁻⁴ [Pa].

  2 and 3, the frame-shaped member 20 has a rectangular frame shape in plan view, with the outer surface and the upper and lower surfaces facing the inner wall surface of the side wall member 18. Has been placed. Near the four corners of the upper and lower surfaces of the frame-shaped member 20, a differential exhaust type static gas bearing 34 (shown only on the upper surface side in FIG. 3) is provided and supported in a non-contact manner with respect to the side wall member 18. . For this reason, this frame-shaped member 20 performs free motion by the action of a horizontal force.

  As shown in FIG. 2, one end of the mover 88 a of the trim motor TM is fixed to the + X side end face of the frame member 20, and the other end of the mover 88 a is an opening formed in the side wall member 18. And exposed to the outside of the side wall member 18. A stator 88b is engaged with the mover 88a from the outside of the side wall member 18, and the frame member 20 is slightly driven in the Y-axis direction by the mover 88a and the stator 88b. A trim motor TM for adjusting the position of the member 20 in the Y-axis direction is configured. The stator 88 b is supported by a support member 89 fixed on the lower plate 19. Although not shown, in practice, the gap between the trim motor TM and the side wall member 18 is substantially maintained in an airtight state by a differential exhaust gas static pressure bearing or other appropriate sealing mechanism. Although not shown, an X-axis trim motor having the same configuration as the trim motor TM may be provided.

  As shown in FIG. 3, Y-axis stators 22a and 22b extending in the Y-axis direction in the vicinity of the −X side end and in the vicinity of the + X side end are respectively provided in the internal space (in the frame) of the frame-shaped member 20. The Y-axis guides 24a and 24b extending in the Y-axis direction are arranged inside the Y-axis stators 22a and 22b, respectively.

  The end portions on the + Y side of each of the Y-axis stators 22a and 22b and the Y-axis guides 24a and 24b are fixed to the inner wall surface on the + Y side of the frame-shaped member 20, and the end portions on the −Y side are The frame member 20 is fixed to the inner wall surface of the side on the −Y side. That is, the Y-axis stators 22a and 22b and the Y-axis guides 24a and 24b are installed between the + Y side and the −Y side of the frame-shaped member 20. In this case, the Y-axis stators 22a and 22b are arranged symmetrically in the plan view, and the Y-axis guides 24a and 24b are arranged symmetrically in the plan view.

  Each of the Y-axis stators 22a and 22b has an XZ cross-section T shape as shown in FIG. 2, and has a plurality of armature coils arranged at a predetermined pitch along the Y-axis direction. Consists of child units. However, as can be seen from FIG. 2, the heights of the Y-axis stator 22a and the Y-axis stator 22b are different. That is, the Y-axis stator 22a is at a higher position than the Y-axis stator 22b, and both are positioned at substantially the same distance on the + Z side and the −Z side from the height position of the center of gravity of the reticle stage RST. So that its height is set.

  As shown in FIG. 2, the Y-axis guides 24a and 24b have an XZ cross-sectional rectangular shape, and the flatness of the four surrounding surfaces (upper surface, lower surface, right side surface, and left side surface) is set high. . The Y-axis guides 24a and 24b are disposed at the same height as the Y-axis stators 22a and 22b, respectively.

  As shown in FIGS. 2 and 3, the reticle stage RST includes a reticle coarse movement stage 28 that moves along Y axis guides 24a and 24b, and an X axis direction and a Y axis relative to the reticle coarse movement stage 28. And reticle fine movement stage 30 that is finely driven by three actuators 54a, 54b, and 54c in the direction and θz direction (the direction of rotation around the Z axis).

  More specifically, the reticle coarse movement stage 28 includes a rectangular plate-like member 42 that is somewhat longer in the X-axis direction, as shown in FIG. 4 showing a perspective view of the reticle stage RST. An L-shaped mounting member 44 fixed to the lower surface of the plate-like member 42 and disposed along the + X-side end surface and the + Y-side end surface of the plate-like member 42, as viewed from above, and the plate-like member A Y-axis slider 46a that extends in the Y-axis direction and is fixed near the −X side end of the lower surface of 42, a Y-axis slider 46b that is fixed to the lower surface of the mounting member 44 and extends in the Y-axis direction, and − Y-axis movers 48a and 48b fixed to the X-side end face and the + X-side end face of the Y-axis slider 46b, respectively.

  As shown in FIGS. 3 and 4, the plate-like member 42 has three round holes (stepped round holes) 64a, 64b located at the vertices of a regular triangle (or isosceles triangle) having a predetermined size. , 64c are formed. Three Z-axis support devices 52a, 52b, and 52c are inserted into these round holes (stepped round holes) 64a, 64b, and 64c, respectively. These Z-axis support devices 52a, 52b, and 52c are supported by the plate-like member 42 in a state where their upper end surfaces are substantially flush with the upper surface of the plate-like member 42. Further, these Z-axis support devices 52a, 52b, 52c suspend and support reticle fine movement stage 30 as an object in a non-contact state. The configuration and operation of the Z-axis support devices 52a, 52b, and 52c will be described in detail later.

  As shown in FIG. 4, the attachment member 44 has an L shape when viewed from the + Z side and a special shape that is substantially L when viewed from the −Y side.

  Each of the pair of Y-axis sliders 46a and 46b has a plurality of differential exhaust gas static pressure bearings provided on the inner surface (four surfaces) of the XZ section having a rectangular frame shape extending in the Y-axis direction. ing. These Y-axis sliders 46a and 46b are attached around the Y-axis guides 24a and 24b described above. In this case, the intervals in the Z-axis direction and the X-axis direction between the Y-axis guides 24a and 24b and the Y-axis sliders 46a and 46b are maintained at about several μm by the plurality of differential exhaust type gas hydrostatic bearings. It has become. Thereby, a guide mechanism for guiding the reticle stage RST (reticle coarse movement stage 28) in the Y-axis direction without contact is realized.

  The Y-axis movers 48a and 48b are arranged on the yoke 54 having a U-shaped cross section and the vertically opposed surfaces inside the yoke 54, as specifically shown for one Y-axis mover 48a in FIG. A plurality of field magnets (N-pole permanent magnets, S-pole permanent magnets 58) arranged at a predetermined pitch and facing each other along the Y-axis direction. In this case, adjacent field magnets 58 are opposed to each other. The magnets 58 have opposite polarities, and an alternating magnetic field is formed in the inner space of the yoke 54 along the Y-axis direction.

  As shown in FIG. 2, the Y-axis movers 48a and 48b engage with the pair of Y-axis stators 22a and 22b, respectively, and move the reticle stage RST in the Y-axis direction. A pair of Y-axis linear motors RMa and RMb composed of force-driven linear motors are respectively configured. A moving coil type linear motor may be used as the Y-axis linear motors RMa and RMb.

  The reticle fine movement stage 30 includes an electrostatic chuck 60, and the reticle R is electrostatically attracted and held by the electrostatic chuck 60. An X-axis moving mirror 62X is extended on the lower surface of the reticle fine movement stage 30 at the −X side end in the Y-axis direction. Although not shown, a Y-axis moving mirror (for example, composed of a pair of retro reflectors or the like) is provided at the −Y side end of reticle fine movement stage 30.

  As shown in FIG. 3, three horizontal driving voice coil motors 54a to 54c are provided between the reticle fine movement stage 30 and the reticle coarse movement stage 28 described above. Of these voice coil motors 54a to 54c, one voice coil motor 54c is provided on the + X side of the reticle fine movement stage 30, as shown in FIGS. 2 and 3, and the other two voice coil motors 54a and 54b. Is provided on the + Y side of the reticle fine movement stage 30.

  Each of these voice coil motors 54a to 54c is composed of an armature unit having a T-shape in a side view fixed to the mounting member 44 side constituting the reticle coarse movement stage 28, as can be understood from FIG. 2 and FIG. And a movable element composed of a magnetic pole unit which is fixed to the reticle fine movement stage 30 side and is finely driven in the arrow direction in FIG. 3 with respect to the stator. That is, reticle fine movement stage 30 is finely driven in the X-axis direction with respect to reticle coarse movement stage 28 by voice coil motor 54c, and Y-axis with respect to reticle coarse movement stage 28 by voice coil motors 54a and 54b. Are driven minutely in the direction and θz direction.

  As shown in FIG. 2, openings 18a and 18b serving as passages for the measurement beam and the reference beam from the X-axis interferometer 32X fixed on the lower plate 19 are formed in a part of the side wall member 18, respectively. Is formed. These openings 18a and 18b are closed by a window glass (not shown) provided on the outer surface side of the side wall member 18, and gas enters the reticle stage chamber RC from the outside through these openings 18a and 18b. Is prevented.

  As shown in FIG. 2, openings 20 a and 20 b are formed in a part of the frame-shaped member 20 at positions facing the above-described openings 18 a and 18 b formed in the side wall member 18, respectively. 18a, the opening 20a, the opening 18b, and the opening 20b form paths for the measurement beam and the reference beam from the X-axis interferometer 32X.

  Although not shown, openings on the −Y side side walls of the side wall member 18 and the frame-shaped member 20 are respectively formed from the Y-axis interferometer (not shown) as paths for the measurement beam and the reference beam. Has been. Of course, also in this case, a window glass is provided on the outer surface side of the side wall member 18 of the opening.

  Below the reticle stage RST (on the −Z side), as shown in FIG. 2, a holding member 98 in which an opening serving as a passage for the illumination light EL is formed at the center is arranged. The holding member 98 is horizontally supported by a pair of support members 99a and 99b fixed to the upper surface of the lens barrel 14 of the projection unit PU. A reticle focus light transmission system 11a is provided in the vicinity of the −X side end portion of the upper surface of the holding member 98, and the wafer focus sensor described above together with the reticle focus light transmission system 11a in the vicinity of the + X side end portion of the upper surface of the holding member 98. A reticle focus light receiving system 11b constituting a reticle focus sensor comprising a multipoint focal position detection system of an oblique incidence method similar to (112a, 112b) is provided. An X-axis fixed mirror 162X is provided on the upper surface of the holding member 98 on the −X side of the reticle focus light transmission system 11a.

  The reference beam from the X-axis interferometer 32X is irradiated to the X-axis fixed mirror 162X through the opening 18b formed in the side wall member 18 and the frame-shaped member 20 and through the opening 20b, and the reflected light is irradiated. Return to the X-axis interferometer 32X. Further, the X-axis interferometer 32X irradiates the X-axis moving mirror 62X through the opening 18a formed in the side wall member 18 and the opening 20a formed in the frame member 20, and the reflected light interferes therewith. Return to a total of 32X. The reflected light of the length measurement beam and the reference beam returned into the X-axis interferometer 32X are synthesized coaxially by the optical system inside the X-axis interferometer 32X, and then the polarization directions are made to coincide with each other through a polarizer. Interferes with The interference light generated by the interference is received by the internal detector, and based on the interference signal corresponding to the interference light, the position information of the reticle fine movement stage 30 in the X-axis direction is converted by the signal processing system (not shown) to the X-axis. For example, the fixed mirror 162X is always detected with a resolution of about 0.5 to 1 nm, for example.

  Although not shown, a Y-axis fixed mirror is provided in the vicinity of the −Y side end portion of the upper surface of the holding member 98. Then, a reference beam is irradiated from a Y-axis interferometer (not shown) to the Y-axis fixed mirror through openings formed on the side wall member 18 and the side wall on the −Y side of the frame-shaped member 20, and the length measuring beam. Are irradiated to each of the Y-axis moving mirrors (for example, a pair of retro reflectors) described above through the openings formed in the side walls on the −Y side of the side wall member 18 and the frame-shaped member 20, respectively. The reflected light of the reference beam and the reflected light of the measuring beam from the Y-axis moving mirror return to the Y-axis interferometer, and the same processing as described above is performed inside the Y-axis interferometer based on the returned light beam, so that it is not shown. With this signal processing system, position information in the Y-axis direction of each of the pair of retroreflectors is always detected with a resolution of, for example, about 0.5 to 1 nm with reference to the fixed mirror. Therefore, based on the measurement values of the respective measurement axes of the Y-axis interferometer, the position of the reticle fine movement stage 30 in the Y-axis direction and θz rotation information can be obtained.

  The measurement values of the X-axis interferometer 32X and the Y-axis interferometer are supplied to a main control device (not shown) together with the measurement values of the reticle focus sensors (11a, 11b), and the main control device uses the linear motors RMa, RMb, The voice coil motors 54a to 54c and the voice coil motors constituting the Z-axis support devices 52a to 52c are controlled to control the position and posture of the reticle fine movement stage 30 in the six-dimensional direction.

  Next, the Z-axis support devices 52a to 52c will be described. Here, one of the Z-axis support devices 52a will be representatively described. The Z-axis support device 52a includes a main body member 170 as a cylindrical member inserted into a round hole 64a formed in the plate-like member 42, as shown in a cross-sectional view in an enlarged manner in FIG. And a slider mechanism 70 which can move relative to the Z-axis direction with respect to 170.

  The main body member 170 has a stepped columnar outer shape in which three cylindrical portions having different diameters, that is, a first portion 171a, a second portion 171b, and a third portion 171c are connected in a concentric state. The lowest first portion 171 a having the smallest diameter is exposed from the lower surface of the plate-like member 42, and the other portions are supported by the plate-like member 42.

  The main body member 170 is formed with a circular opening 170a having a predetermined depth from the upper end surface of the first portion 171a to an intermediate position in the height direction of the second portion 171b and formed at the center position of the main body member 170. A circular hole 170b concentric with the circular opening extending from the inner bottom surface to the lower end surface of the third portion 171c is formed at the center of the inner bottom surface of the circular opening 170a. In other words, the circular opening 170a and the round hole 170b form a stepped through hole in which the diameter of the upper part is set to be larger than the other part slightly above the central position in the height direction. .

  The slider mechanism 70 has a vertical direction (Z-axis direction) as a longitudinal direction, and the remaining part except for a part of the lower end is inserted into a stepped through hole formed in the body member 170 described above. And a tip member 70b connected to the lower end of the slider 70a through a bellows 70c in a non-contact manner and allowed to rotate around the X axis and around the Y axis. .

  The slider 70a is formed such that a part of the upper end (+ Z side end) and a part of the lower end are larger in diameter than other parts. The large-diameter portion 270a on the upper end side is formed in a columnar shape, and a recess 103 having a predetermined depth is formed in the center thereof. On the other hand, the large-diameter portion 270c on the lower end side is connected to the small-diameter portion 270b via a tapered portion. Further, a concave surface (curved surface) is formed on a part of the lower end surface of the slider 70a.

  A plurality of, for example, four permanent magnets 78 are embedded in a substantially central portion in the Z-axis direction of the slider 70a on the side surfaces on the + X side and the −X side at predetermined intervals in the Z-axis direction. In this case, two magnets arranged side by side in the Z-axis direction have opposite polarities.

In the slider 70a, the main body side supply line 94, the first main body side suction line 96a and the second main body side supply line 94 are communicated with the inner bottom surface of the recess 103 and the lower end part (the −Z side end part). Main body side suction pipes 96b are respectively formed. In this case, the main body side supply pipe 94 is formed at substantially the center of the XY cross section of the slider 70a, and the first main body side suction pipe 96a and the second main body side suction pipe are provided on both sides of the main body side supply pipe 94. Each path 96b is formed. One end of each of the supply pipe 104, the first suction pipe 106a, and the second suction pipe 106b is connected to the upper end (+ Z side end) of each pipe line via a connector CN. Among these, the other end of the supply pipe 104 is connected to a gas supply device (not shown) that supplies gas of a predetermined pressure. The other end of the first suction tube 106a is connected to a low vacuum (about 10 ² to 10 ³ Pa) suction device (vacuum pump) not shown, and the other end of the second suction tube 106b is The suction device (vacuum pump) of high vacuum (about 10 ⁻² to 10 ⁻³ Pa) (not shown) is connected.

  The tip member 70b has a lower surface that can be opposed to the upper surface of the reticle fine movement stage 30 via a predetermined clearance (for example, about several μm), and the opposite surface is a lower end surface of the slider 70a. The concave surface formed in a part is a spherical surface that can partly face through a predetermined clearance (for example, about several μm or less). A permanent magnet 72 is embedded in the center of the lower surface of the tip member 70b, and an ejection groove 74 as an ejection portion is formed around the permanent magnet 72. Also, an annular first suction groove 76a is formed on the lower surface of the tip member 70b so as to surround the periphery of the ejection groove 74, and further, so as to surround the periphery of the first suction groove 76a. An annular second suction groove 76b is formed.

  In the tip member 70b, a tip portion side supply conduit 84 that communicates the ejection groove 74 and the outside of the upper surface of the tip member 70b is formed in the vertical direction. The distal end member 70b includes a first distal end side suction conduit 86a that communicates the first suction groove 76a with the outside of the upper surface of the distal end member 70b, and an upper surface of the second suction groove 76b and the distal end member 70b. Second tip side suction pipes 86b communicating with the outside are respectively formed.

  That is, when a pressurized gas is supplied from a gas supply device (not shown) via the supply pipe 104, the pressurized gas passes between the slider 70a and the tip member 70b via the first main body side supply pipe 94. The pressurized gas filled in the clearance reaches the first distal end side supply conduit 84. Then, this pressurized gas is ejected from the ejection groove 74 to the surface of the reticle fine movement stage 30.

  On the other hand, the pressurized gas ejected from the ejection groove 74 as described above flows out toward the periphery of the ejection groove 74 via the clearance between the tip member 70b and the surface of the reticle fine movement stage 30. At this time, if a first vacuum pump (not shown) is operating, the first suction pipe 106a, the first suction pipe 96a, and the first tip are caused by the action of the vacuum suction force generated by the vacuum pump. The inside of the part-side suction conduit 86a is sequentially in a negative pressure state. In this case, it goes without saying that the inside of the first suction pipe 106a is at the highest vacuum, and the inside of the first tip side suction pipe 86a is in the lowest vacuum state. Accordingly, the pressurized gas that has flowed out toward the periphery of the ejection groove 74 flows from the first suction groove 76a to the first tip side suction pipe 86a, the first suction pipe 96a, and the first suction pipe 106a. Are sequentially collected by the first vacuum pump and exhausted.

  In addition, when the second vacuum pump (not shown) is operating, the remaining pressurized gas that could not be recovered through the first suction groove 76a is transferred from the second suction groove 76b to the second as in the above. The two suction pipes 86b, the second suction pipe 96b, and the second suction pipe 106b are sequentially collected and exhausted by the second vacuum pump.

  As described above, in this embodiment, the tip member 70b including the ejection groove 74, the first suction groove 76a, and the second suction groove 76b is used as a differential as the first hydrostatic bearing mechanism shown in FIG. An exhaust-type hydrostatic bearing mechanism is configured. Hereinafter, the tip member 70b is also described as a hydrostatic bearing mechanism 70b as necessary. In the hydrostatic bearing mechanism 70b, an ejection portion that ejects gas to the object is configured by the ejection groove 74, and the first suction groove 76a collects the gas using a vacuum around the ejection portion. A first recovery unit configured to recover the gas at a higher vacuum than the first recovery unit around the first recovery unit by the second suction groove 76b. Yes.

  In the present embodiment, the above-described permanent magnet 72 is provided at the center of the bottom surface of the tip member 70b, and at least a part of the reticle fine movement stage 30 including a portion facing the permanent magnet 72 is made of a magnetic material. Has been. Therefore, the reticle fine movement stage 30 is attracted to the tip member 70b against the static pressure of the pressurized gas ejected from the static pressure bearing mechanism 70b by the magnetic attraction force of the permanent magnet 72. . That is, the preload mechanism using magnetic force is constituted by the permanent magnet 72 and the magnetic body. Hereinafter, it is also referred to as “preload mechanism 72” as necessary. In the present embodiment, a force (repulsive force) for separating the tip member 70b and the reticle fine movement stage 30 by the static pressure of the pressurized gas, and the tip member 70b and the reticle fine movement stage 30 generated by the preload mechanism 72 are combined. The reticle fine movement stage is based on the balance between the force (attractive force) to be approached (more precisely, the resultant force of the attractive force and the attractive force due to the negative pressure generated in the vicinity of the first suction groove 76a and the second suction groove 76b). A predetermined clearance (for example, several μm) is maintained between 30 and the tip member 70b.

  In the portion of the main body member 170 where the round hole 170b is formed, the armature coil is substantially opposed to the two permanent magnets 78 provided on the side surfaces of the slider mechanism 70 on the + X side and the −X side. One 178 is provided. A Lorentz force in the Z-axis direction acts on each armature coil 178 due to an electromagnetic interaction between the current flowing through each armature coil 178 and the magnetic field generated by the permanent magnet 78, and the reaction force of this Lorentz force acts on the slider mechanism 70. The driving force is driven in the Z-axis direction. That is, in the present embodiment, the permanent magnet 78 and the armature coil 178 constitute a voice coil motor as a non-contact type driving device. The number and arrangement of the permanent magnets on the slider mechanism 70 side described above and the number and arrangement of the armature coils on the main body member 170 side are not particularly limited. In short, the slider mechanism 70 is driven in the Z-axis direction. Any configuration that can generate the driving force to be generated is acceptable.

  A liquid chamber 180 is formed near the armature coil 178 of the main body member 170. The liquid chamber 180 is supplied with a cooling liquid from a liquid supply device (not shown) provided outside via a liquid supply pipe 200a and a liquid supply pipe 190a. Heat exchange is performed between the coolant in the liquid chamber 180 and the armature coil 178, and the armature coil 178 is cooled. The cooling liquid in the liquid chamber 180 whose temperature has been increased by this heat exchange is recovered by a liquid recovery device (not shown) provided outside via the liquid recovery pipe line 190b and the liquid recovery pipe 200b. The temperature of the liquid inside 180 is always kept at a predetermined temperature. That is, in the present embodiment, the armature coil is formed by using the cooling liquid supplied from the liquid supply device (not shown) through the liquid supply pipe 200a by the liquid supply pipe line 190a, the liquid chamber 180, and the liquid recovery pipe line 190b. A temperature adjustment mechanism for adjusting the temperature of the voice coil motor is configured by cooling 178 and allowing the liquid recovery apparatus to recover the cooled coolant after the cooling.

In addition, an air supply groove 114 having a predetermined width in the Z-axis direction and a predetermined depth is formed on the inner wall of the opening 170a portion of the main body member 170. Low-vacuum suction grooves 116a ₁ and 116a ₂ are formed which are narrower and deeper than the groove 114 and extend over the entire circumference of the inner wall. Furthermore, the further upper position of the upper low vacuum suction grooves 116a ₁ are low vacuum suction grooves 116a _1, 116a ₂ and substantially the same width, the high vacuum suction grooves 116b of the same depth are formed over the entire periphery of the inner wall ing.

One end of an L-shaped air supply pipe 124 formed in the main body member 170 is connected to the air supply groove 114, and the other end of the air supply pipe 124 is connected to a gas supply device (not shown) via an air supply pipe 134. It is connected to the. The low vacuum suction grooves 116a ₁ and 116a ₂ are connected to respective branched ends of a low vacuum suction pipe 126a formed in a part of the body member 170, and the low vacuum suction pipe 126a. The end is connected to a low vacuum (about 10 ² to 10 ³ Pa) suction device (not shown) via a low vacuum suction pipe 136a. Further, one end of an L-shaped high vacuum suction pipe 126b formed in the main body member 170 is connected to the high vacuum suction groove 116b, and the other end of the suction pipe 126b is connected via a high vacuum suction pipe 136b. It is connected to a high vacuum (about 10 ⁻² to 10 ⁻³ Pa) suction device (not shown).

  In this case, when pressurized gas is supplied from a gas supply device (not shown) via the air supply pipe 134, the pressurized gas reaches the entire circumference of the air supply groove 114 via the air supply pipe 124. It is ejected toward the large-diameter portion 270a on the upper end side of the slider 70a. Due to the static pressure of the ejected pressurized gas, the space between the large-diameter portion 270a on the upper end side of the slider 70a and the inner wall surface of the opening 170a of the main body member 170. A predetermined clearance (for example, about several μm) is formed on the substrate. In this case, since the pressurized gas exists over the entire circumference of the slider 70a, a predetermined clearance is formed over the entire circumference due to the balance between the static pressures, and the clearance is maintained as long as the pressurized gas is ejected. Is done.

On the other hand, the pressurized gas ejected from the air supply groove 114 as described above is within the clearance between the large diameter portion 270a on the upper end side of the slider 70a and the inner wall surface of the opening 170a of the main body member 170. It extends to the space above and below 114. At this time, if a low-vacuum suction device (not shown) is operating, most of the pressurized gas that has expanded in the clearance as described above is composed of low vacuum suction grooves 116a ₁ and 116a ₂ , low vacuum. It is collected by a low vacuum suction device through the suction conduit 126a and the low vacuum suction tube 136a in order, and exhausted outside the device. In this case, when the high vacuum suction device is operating, the remaining pressurized gas that could not be recovered through the low vacuum suction grooves 116a ₁ and 116a ₂ is discharged from the high vacuum suction groove 116b as described above. The high vacuum suction pipe 126b and the high vacuum suction pipe 136b are sequentially passed through the high vacuum suction device to be recovered and exhausted outside the device.

As described above, in the present embodiment, a predetermined pressure is provided between the large-diameter portion 270a on the upper end side of the slider 70a and the inner wall surface of the opening 170a of the main body member 170 due to the static pressure of the pressurized gas ejected from the air supply groove 114. The clearance can be formed and maintained. Further, since the pressurized gas in the clearance is forcibly discharged to the outside through the low vacuum suction grooves 116a ₁ and 116a ₂ and the high vacuum suction groove 116b, the gas is supplied to the internal space of the reticle stage chamber RC. It is almost certainly possible to avoid leakage.

In the present embodiment, the differential shown in FIG. 5 is provided by the vicinity of the inner wall surface of the opening 170a of the main body member 170 in which the air supply groove 114, the low vacuum suction grooves 116a ₁ and 116a ₂ and the high vacuum suction groove 116b are formed. An exhaust-type hydrostatic bearing mechanism 101 is substantially constituted. In this case, the air supply groove 114 constitutes an ejection portion for ejecting gas into the predetermined clearance, and the low vacuum suction grooves 116a ₁ and 116a ₂ collect the gas using a vacuum around the ejection portion. And a second recovery unit configured to recover the gas at a higher vacuum than the first recovery unit around the first recovery unit by the high vacuum suction groove 116b. Yes.

  Further, in the present embodiment, as shown in FIG. 5, the differential exhaust type hydrostatic bearing mechanism 102 is substantially constituted by the vicinity of the lower end portion of the inner wall of the round hole 170 b portion of the main body member 170. . The hydrostatic bearing mechanism 102 is configured in the same manner as the hydrostatic bearing mechanism 101 described above, but is not described in detail.

  A predetermined clearance is formed and maintained between the small diameter portion 270b of the slider 70a and the inner wall surface of the round hole 170b of the body member 170 by the static pressure of the pressurized gas ejected from the air supply groove of the static pressure bearing mechanism 102. The pressurized gas in the clearance can be forcibly discharged to the outside through the low vacuum suction groove and the high vacuum suction groove, so that the gas leaks into the internal space of the reticle stage chamber RC. Can be avoided almost certainly.

  A gas chamber 109 is formed between the upper end portion of the slider mechanism 70, that is, the large-diameter portion 270 a on the upper end side of the slider main body 70, and the inner wall surface (including the inner bottom surface) of the circular opening 170 a of the main body member 170. ing. The gas chamber 109 is communicated with a space outside the reticle stage chamber RC via a ventilation path 118 formed in the main body member 170 and a pipe 128 connected to the ventilation path 118. A part of the air passage 118 is branched in the middle.

  Further, as shown in FIG. 5, an annular air chamber 108 having a predetermined internal volume is formed in the first portion 171 c of the main body member 170. The air chamber 108 is connected to the branch end portion of the air passage 118 described above. In other words, the air chamber 108 communicates with the external space of the reticle stage chamber RC via the vent path 118 and the pipe 128 and also communicates with the gas chamber 109 via the vent path 118.

  Since the gas chamber 109, the vent path 118, and the air chamber 108 are configured as described above, air outside the reticle stage chamber RC flows into the gas chamber 109 via the pipe 128 and the vent path 118, and as a result. The pressure of the air inside the gas chamber 109 is about the same atmospheric pressure as the atmosphere outside the reticle stage chamber RC. That is, the inside of the gas chamber 109 is released to the atmosphere outside the reticle stage chamber RC.

  Air outside the reticle stage chamber RC also flows into the air chamber 108 via the pipe 128 and the air passage 118, and the air chamber 108 is also filled with atmospheric air. That is, when the gas (air) in the gas chamber 109 decreases with time, the air is replenished from the outside via the pipe 128 and the air passage 118. At this time, if the pressure loss occurs when the air passes through the pipe 128, the pressure of the air in the air chamber 108 becomes higher than the pressure of the air supplied through the pipe 128. Air in the chamber 108 is preferentially supplied into the gas chamber 109 through the air passage 118. In this way, the pressure of the air in the gas chamber 109 is maintained almost at atmospheric pressure. That is, in this embodiment, the air chamber 108 constitutes a buffer unit for maintaining the pressure of the gas (in this case, air) in the gas chamber 109 at a predetermined pressure (in this case, atmospheric pressure). It should be noted that external air is supplied to the air chamber 108 whose internal pressure has decreased due to the supply of air to the gas chamber 109 via the pipe 128 and the ventilation path 118, and as a result, the internal pressure of the air chamber 108 is It becomes atmospheric pressure again.

  As can be seen from the above description, a supply device that supplies gas (air) at a predetermined pressure (atmospheric pressure) to the gas chamber 109 is configured by the air passage 118, the air chamber 108, and the pipe 128.

  Since the other Z-axis support devices 52b and 52c are configured in exactly the same manner as the Z-axis support device 52a, detailed description thereof is omitted.

  According to the three Z-axis support devices 52a to 52c configured as described above, the entire reticle stage RST is arranged in a vacuum atmosphere, so that the air inside the gas chamber 109 of the Z-axis support devices 52a to 52c Each slider mechanism 70 and the own weight of the reticle fine movement stage 30 supported by each slider mechanism 70 can be supported by the differential pressure between the pressure and the vacuum atmosphere. Therefore, it is not necessary to obtain a supporting force for supporting the own weight of reticle fine movement stage 30 by a driving force of an actuator such as a voice coil motor.

  Further, in the Z-axis support devices 52a to 52c, the reticle fine movement stage 30, which is a support object, can be suspended and supported in a non-contact manner with respect to the reticle coarse movement stage 28 to which they are attached. Each main body member 170 can be supported without contact. In the Z-axis support devices 52a to 52c, the slider mechanisms 70 can be independently driven in the Z-axis direction as necessary by the voice coil motors (78, 178).

  In this case, since the three Z-axis support devices 52a to 52c are provided at three positions that are not in a straight line, the driving force in the Z-axis direction generated by each of the Z-axis support devices 52a to 52c has the same magnitude. As a result, the reticle fine movement stage 30 can be finely driven in the Z-axis direction and the reticle fine movement can be achieved by varying the magnitude of the driving force in the Z-axis direction generated by each of the Z-axis support devices 52a to 52c. The stage 30 can be finely driven in the rotation direction (θx direction) around the X axis and the rotation direction (θy direction) around the Y axis. In this case, the tip member 70b of each slider mechanism 70 is freely rotatable about the X axis and the Y axis with respect to each slider 70a. The distance between tip member 70b and reticle fine movement stage 30 can be maintained at a predetermined distance. Further, each bellows 70c can prevent gas from flowing out from the gap between each slider 70a and each tip member 70b.

  Next, an exposure operation by the exposure apparatus 10 of the present embodiment configured as described above will be described.

  First, reticle R is transported by a reticle transport system (not shown), and is sucked and held on reticle stage RST at the loading position. Next, the positions of wafer stage WST and reticle stage RST are controlled by a main controller (not shown), and a projection image of a reticle alignment mark (not shown) formed on reticle R on the wafer W surface is an aerial image. The projection position of the reticle alignment mark on the surface of the wafer W detected by the measuring instrument FM is obtained. That is, reticle alignment is performed.

  Next, the main controller moves the wafer stage WST so that the aerial image detector FM is positioned immediately below the alignment detection system (not shown), and the detection signal of the alignment detection system and the measurement of the wafer interferometer 82W at that time are detected. Based on the position, an image formation position of the pattern image of the reticle R on the surface of the wafer W and a relative distance between the alignment detection system, that is, a baseline is obtained indirectly.

  When the baseline measurement is completed, the main controller performs wafer alignment (for example, EGA), and the position information of all shot areas on the wafer W (for example, a stage defined by the measurement axis of the wafer interferometer). Position coordinates on the coordinate system) is obtained.

  Then, under the control of the main controller, the wafer is placed at the scanning start position (acceleration start position) for exposure of each shot area on the wafer W using the above-described baseline measurement result and wafer alignment result. Step-and-scan exposure is the same as that of a normal scanning stepper (scanner), in which the operation of moving the stage WST and the operation of transferring the reticle pattern to the shot area by the scanning exposure method are alternately repeated. To be done.

  As described above, in the exposure apparatus 10, the processing of the exposure process is executed in the same procedure as that of a normal scanner. However, during the scanning exposure, the main controller determines the position and posture of the wafer stage WST in the 6 degrees of freedom direction. In addition to the control, the position and posture control of the reticle fine movement stage 30 in the six-dimensional direction is also executed as described above.

  As described above in detail, according to the Z support devices 52a to 52c according to the present embodiment, the differential pressure (pressure difference) between the gas (air) in each gas chamber 109 provided in the Z support devices 52a to 52c and the vacuum atmosphere. ) Supports the own weight of reticle fine movement stage 30 (including the own weight of reticle R). Therefore, an actuator for constantly generating a supporting force for supporting the own weight of reticle fine movement stage 30 is not necessary, and various inconveniences caused by the heat generated by the actuator do not become a problem. Further, the reticle fine movement stage 30 can be held in a non-contact manner by the preload mechanism 72 and the hydrostatic bearing mechanism 70b provided on each tip member 70b, so that the vibration on the reticle coarse movement stage 28 side is vibrated on the reticle fine movement stage 30 side. Can be reduced. Further, each slider mechanism 70 provided with each hydrostatic bearing mechanism 70b has an inner peripheral surface (an inner peripheral surface of the opening 170a, an inner peripheral surface of the round hole 170b) formed in the main body member 170 and extending in the vertical direction. Therefore, the reticle fine movement stage 30 is also allowed to move in the vertical direction and in the θz direction and the θy direction.

  Further, according to the Z-axis support mechanisms 52a to 52c of the present embodiment, the drive of each slider mechanism 70 constituting each of the Z-axis support mechanisms 52a to 52c is a voice coil motor (78, 178) which is a non-contact type drive device. However, each of the Z-axis support mechanisms 52a to 52c includes a temperature adjustment mechanism (190a, 180, 190b) that adjusts the temperature of the voice coil motor. It is possible to suppress the thermal effect on

  In addition, according to reticle stage device 12 according to the present embodiment, Z axis support devices 52a to 52c are provided in which the problem of heat generation of the actuator for constantly generating a support force for supporting the own weight of reticle fine movement stage 30 is eliminated. Since the reticle stage RST is provided, it is possible to reduce the thermal influence on the members and atmosphere around the reticle stage RST. That is, the reticle focus sensor that measures the position information of the reticle stage RST in the Z-axis direction and the θx, θy directions, more precisely the position information of the reticle R held on the reticle stage RST in the Z-axis direction and the θx, θy directions. It is possible to effectively prevent the measurement accuracy of 11a and 11b from being affected and lowered by the heat generated by the actuator. In this respect, the position controllability of reticle stage RST can be improved.

  In reticle stage device 12 according to the present embodiment, a pair of linear motors RMa and RMb are provided with their positions in the Z-axis direction shifted. Accordingly, even when one of the linear motors needs to be arranged on the + Z side with respect to the center of gravity of the reticle stage RST due to the influence of the beam position of the interferometer 32X as in the present embodiment, the driving point of the other linear motor Is set at a position symmetrical to the drive point of one of the linear motors with respect to the center of gravity, the center of gravity of the reticle stage RST can be driven, and the position of the reticle stage RST can be controlled with high accuracy.

  Further, according to the exposure apparatus 10 of the present embodiment, the reticle stage apparatus 12 having improved position controllability of the reticle stage RST is provided, and the reticle stage RST is driven in synchronization with the wafer stage WST, so that the reticle R is Since the formed pattern is transferred to each of a plurality of shot areas on the wafer W, it is possible to form a highly accurate pattern on the wafer as a result.

  In the above embodiment, the case where the reticle fine movement stage 30 is supported at three points using the three Z-axis support devices 52a to 52c has been described. However, this is only for the position control of the reticle fine movement stage 30 in the Z-axis direction. However, in the case where leveling control is not necessary, the reticle fine movement stage 30 may of course be supported by a single Z-axis support device.

  In the above-described embodiment, all of the hydrostatic bearing mechanism 70b and the hydrostatic bearing mechanisms 101 and 102 are provided with a low vacuum suction groove and a high vacuum suction groove in addition to the ejection groove or the supply groove corresponding to the ejection groove. However, this is done from the viewpoint of reliably preventing leakage of pressurized gas into the high vacuum space inside the reticle stage chamber RC. Therefore, if some gas leakage can be allowed, one or both of the low vacuum suction groove and the high vacuum suction groove may not be provided.

  Moreover, although the said embodiment demonstrated the case where the supply apparatus was comprised also including the air chamber 108 as a buffer part other than the ventilation path 118 and the piping 128, this is gas (air) inside the gas chamber 109. ) Is maintained in this manner in order to maintain the pressure of) at about atmospheric pressure. Therefore, when the fluctuation of the pressure of the gas (air) inside the gas chamber 109 can be tolerated or when another configuration for preventing the fluctuation of the pressure of the gas (air) inside the gas chamber 109 is adopted, the buffer section ( The air chamber 108) is not necessarily provided. As another configuration for preventing the fluctuation of the pressure of the gas (air) inside the gas chamber 109, for example, the end of the pipe 128 opposite to the vent path 118 is connected to the pressurized gas via a pressure adjusting mechanism such as a regulator. A sensor is connected to the supply source to detect the pressure of the gas inside the gas chamber 109, and the regulator is controlled based on the detection value of the sensor, so that the pressure of the gas (air) inside the gas chamber 109 is set to a desired value. A configuration that maintains the value can be adopted.

  In the above-described embodiment, the case where the Z-axis support device that suspends and supports reticle fine movement stage 30 of reticle stage RST from reticle coarse movement stage 28 is provided as an object support device, but is supported on wafer stage WST side. An apparatus may be provided. That is, when a wafer stage apparatus having a coarse / fine movement structure including a stage that moves in a two-dimensional plane and a wafer table that can be finely driven in the Z, θx, and θy directions with respect to the stage is adopted as wafer stage WST. In this configuration, three Z-axis support devices 52 ′ as support devices as shown in FIG. 6 are arranged on the stage, and the wafer table WTB is supported at three points by the three Z-axis support devices 52 ′. Can be adopted. In addition, the code | symbol ST in FIG. 6 shows a stage.

  The Z-axis support device 52 'shown in FIG. 6 is obtained by turning the Z-axis support device 52a shown in FIG. 5 upside down and partially changing the configuration.

  This Z-axis support device 52 ′ differs from the Z-axis support device 52a of FIG. 5 in that the gas chamber 109 ′ includes a lid member 202 that closes the circular opening 170a of the main body member 170, a first portion 171a of the slider 70a, A force in the + Z direction is applied to the slider mechanism 70 by atmospheric pressure gas (air) formed (partitioned) by the inner wall of the circular opening 170a of the main body member 170 and sent to the gas chamber 109 ′. It has become. Further, the difference is that air supply and suction to the hydrostatic bearing mechanism 70 b are performed via the hydrostatic bearing mechanism 101.

  Other configurations, that is, a hydrostatic bearing mechanism 70b and a preload mechanism 72 (provided on the permanent magnet 72 and the wafer table WTB side) that maintain a predetermined distance between the wafer table (WTB) and the tip member 70b of the slider mechanism 70. A static pressure bearing mechanism 101, 102, an air chamber (buffer part) 108, a permanent magnet 78 and a coil 178 that maintain a predetermined distance between the slider 70a and the inner wall of the main body member 170. The configuration of a voice coil motor or the like constituted by

  By adopting such a Z-axis support device 52 ′, the wafer table WTB can be supported on the stage ST in a non-contact manner as in the above embodiment, and the heat generation of the Z-axis support device 52 ′ is effective. Therefore, it is possible to suppress the outflow of gas to the outside of the Z-axis support device 52 ′.

  In the above embodiment, the preload mechanism 72 (permanent magnet) using magnetic force is used as the preload mechanism that uses the hydrostatic bearing mechanism 70b and generates a preload that resists the force applied to the reticle fine movement stage 30 by the hydrostatic bearing mechanism 70b. 72 and a magnetic material member provided on reticle fine movement stage 30), the present invention is not limited to this. For example, a preload mechanism as shown in FIG. 7 can be used.

  In the configuration of FIG. 7, instead of the slider 70a, a slider 70a ′ having a large-diameter portion at the lower end portion and having a spherical concave bottom surface is used, and the upper end surface of the tip member is the concave surface. A tip member 70b ′ having a spherical convex surface to be engaged and having a T-shaped longitudinal section is used. Further, in the configuration of FIG. 7, an extending portion 204 is provided on the upper surface of the reticle fine movement stage 30 so as to surround the tip member 70 b ′ from above and from the side. In FIG. 7, the slider 70a ', the supply pipe, the suction pipe, and the like inside the tip member 70b' are not shown.

  At the tip of the tip member 70b ', a jet groove 74' for jetting pressurized gas is also applied to the surface (upper surface) opposite to the jet groove 74, and a first gas that sucks high-pressure gas in a low vacuum. A suction groove 76a ′ and a second suction groove 76b ′ for sucking high-pressure gas in a high vacuum are provided. That is, by forming a differential exhaust gas static pressure bearing mechanism including these grooves 74 ′ and 76 a ′ 76 b ′, a pressurized gas in the clearance between the gas static pressure bearing mechanism and the extending portion 204 is formed. Due to the static pressure of the pressurized gas ejected from the hydrostatic bearing mechanism including the ejection groove 74, the first suction groove 76a and the second suction groove 76b to the object (reticle fine movement stage 30). It can be used as a preload against the force. It is possible to balance the static pressure of the pressurized gas between the tip member 70 b ′ and the extending portion 204 and the static pressure of the pressurized gas between the tip member 70 b ′ and the reticle fine movement stage 30.

  In the above embodiment, a configuration including a groove formed in a part of the main body member 170 is adopted as the hydrostatic bearing mechanisms 101 and 102. However, the present invention is not limited to this, and the hydrostatic bearing mechanism is the main body member 170. Another member may be used, and the hydrostatic bearing mechanism may be attached to the main body member 170.

  In the above embodiment, the hydrostatic bearing mechanisms 101 and 102 are provided at two locations on the main body member 170. However, the present invention is not limited to this, and there is almost no risk of gas outflow from the gas chamber 109. At least one of the hydrostatic bearing mechanisms 101 and 102 may not be provided.

  In the above-described embodiment, the case where the voice coil motor, which is a non-contact driving device, is employed as the driving device that drives the slider mechanism 70 with respect to the main body member 170, but the present invention is not limited thereto. Instead, for example, various driving devices may be employed as long as the driving device linearly drives the slider, such as a linear motor or a ball screw type driving device.

  Further, in the above embodiment and the modification, the case where the Z-axis support device as the support device of the present invention is used in the stage device (reticle stage device and wafer stage device) constituting the exposure apparatus has been described. However, the present invention can be used for various purposes as long as it supports a predetermined object in a vacuum atmosphere in other parts of the exposure apparatus and other apparatuses.

In the above embodiment, the case where EUV light is used as the exposure light and the all-reflection projection optical system including only four mirrors is used has been described as an example, and the present invention is not limited thereto. Of course. That is, for example, an exposure apparatus having a projection optical system composed of only six mirrors, as well as a VUV light source having a wavelength of 100 to 160 nm, for example, an Ar ₂ laser (wavelength 126 nm) as a light source, and 4 to 8 mirrors. A projection optical system having the same can also be used. The projection optical system may be either a refractive projection optical system consisting only of a lens or a catadioptric projection optical system including a lens in part.

  In the above embodiment, the case where EUV light having a wavelength of 11 nm is used as exposure light has been described. However, the present invention is not limited to this, and EUV light having a wavelength of 13 nm may be used as exposure light. In this case, in order to secure a reflectance of about 70% with respect to EUV light having a wavelength of 13 nm, it is necessary to use a multilayer film in which molybdenum Mo and silicon Si are alternately laminated as the reflection film of each mirror.

  In the above embodiment, SOR (Synchrotron Orbital Radiation) is used as the exposure light source. However, the present invention is not limited to this, and any of a laser excitation plasma light source, a betatron light source, a discharged light source, an X-ray laser, and the like is used. Also good.

  As described above, the support device of the present invention is suitable for supporting an object in a vacuum atmosphere. The stage apparatus of the present invention is suitable for moving an object in a predetermined direction within a moving plane. The exposure apparatus of the present invention is suitable for forming a pattern by exposing a substrate.

It is a figure which shows schematically the structure of the exposure apparatus of one Embodiment. It is a longitudinal cross-sectional view of a reticle stage apparatus. It is a top view which shows the structural part of the reticle stage apparatus accommodated in the inside of a reticle stage chamber. It is a perspective view which shows a reticle stage. It is a longitudinal cross-sectional view which shows a Z-axis support apparatus. It is a figure which shows the modification of a Z-axis support apparatus. It is a figure for demonstrating the other example of a preload mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Exposure apparatus, 12 ... Reticle stage apparatus (stage apparatus), 30 ... Reticle fine movement stage (object), 52a-52c ... Z-axis support apparatus (support apparatus), 70 ... Slider mechanism, 70a ... Slider, 70b ... 1st , 72 ... Permanent magnet (preload mechanism), 74 ... Ejection groove (ejection part), 76a ... First suction groove (first recovery part), 76b ... Second suction groove (second 2), 78 ... Permanent magnet (a part of a non-contact type driving device), 101 ... Hydrostatic bearing mechanism (second hydrostatic bearing mechanism), 102 ... Hydrostatic bearing mechanism (second static pressure) Bearing mechanism), 108 ... air chamber (buffer part, part of the supply device), 109 ... gas chamber, 118 ... vent passage (part of the supply device), 114 ... air supply groove (spouting part), 116a ₁ , 116a ₂ ... low vacuum suction grooves (first collecting portion), 116 b ... high vacuum (Second recovery unit), 128 ... piping (part of supply device), 170 ... main body member (cylindrical member), 178 ... coil (part of non-contact type driving device), 180 ... liquid chamber (temperature) Part of adjusting mechanism), 190a ... liquid supply line (part of temperature adjusting mechanism), 190b ... liquid recovery line (part of temperature adjusting mechanism), RST ... reticle stage (stage), RMa ... linear motor ( Drive device), RMb ... linear motor (drive device), W ... wafer (substrate).

Claims (13)

A support device used in a vacuum atmosphere to support an object,
A first hydrostatic bearing mechanism facing the object;
A tubular member having an inner peripheral surface extending in a vertical direction;
A slider that is coupled to one end of the first hydrostatic bearing mechanism and is movable along the inner peripheral surface;
A gas chamber formed by the tubular member and the other end of the slider;
And a supply device for supplying a gas having a predetermined pressure to the gas chamber so as to support the dead weight of the object by a differential pressure with respect to the vacuum atmosphere.   The support device according to claim 1, wherein the slider is moved by a non-contact type driving device.   The support device according to claim 2, further comprising a temperature adjustment mechanism that adjusts a temperature of the non-contact type driving device.   The first hydrostatic bearing mechanism includes an ejection unit that ejects a gas to the object, a first recovery unit that collects the gas using a vacuum around the ejection unit, and the first 4. The support device according to claim 1, further comprising a second recovery unit that recovers the gas at a higher vacuum than the first recovery unit around the recovery unit. .   5. The second hydrostatic bearing mechanism for forming a clearance along the vertical direction is provided between the cylindrical member and the slider. The support device as described.   The second hydrostatic bearing mechanism includes an ejection portion that ejects gas into the clearance, a first recovery portion that collects the gas using a vacuum around the ejection portion, and the first The support device according to claim 5, further comprising a second recovery unit that recovers the gas at a higher vacuum than the first recovery unit around the recovery unit.   The support device according to any one of claims 1 to 6, further comprising a preload mechanism that generates a preload that resists a force applied to the object by the first hydrostatic bearing mechanism.   The support device according to claim 1, wherein the supply device includes an air passage formed in the cylindrical member and communicating with the gas chamber.   The support device according to claim 8, wherein the gas chamber communicates with the atmosphere through the ventilation path.   The support device according to claim 1, wherein the supply device includes a buffer portion that is formed on the cylindrical member and can store the gas having the predetermined pressure.   A stage device comprising a stage movable in a two-dimensional plane having the support device according to claim 1. A pair of driving devices for driving the stage in a predetermined uniaxial direction;
The stage device according to claim 11, wherein the pair of driving devices are provided by shifting the position in the vertical direction. In an exposure apparatus that drives a stage device to expose a substrate and forms a pattern on the substrate,
An exposure apparatus, wherein the stage apparatus is the stage apparatus according to claim 11 or 12.

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