JP2006165345A - Stage apparatus, exposure apparatus, and method for manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stage apparatus capable of achieving speeding-up of a stage, and also, capable of suppressing heat generation. <P>SOLUTION: The stage apparatus 20 is provided with the stage 202 movable in a prescribed direction; first driving apparatuses 220, 260, and 270 for imparting force in the prescribed direction to the stage; and second driving apparatuses 230, 240, and 250 which are provided separately from the first driving apparatuses 220, 260, and 270 and impart force in the prescribed direction to the stage 202. The second driving apparatuses 230, 240, and 250 generate the force in the prescribed direction by magnetic attraction force generated between two objects whose opposite faces are respectively nearly in parallel with the prescribed direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus used in a photolithography process for manufacturing a semiconductor element, a liquid crystal display element, an imaging element, a thin film magnetic head, and other fine devices, and a stage apparatus suitably used for the exposure apparatus.

  In an exposure apparatus (microlithography apparatus), illumination light (energy rays such as ultraviolet rays, X-rays, and electron beams) is irradiated onto a mask or the like on which a circuit pattern is drawn, so that the projection has the same magnification, a predetermined reduction magnification or enlargement magnification. Projection exposure is performed on a sensitive substrate (such as a semiconductor wafer or a glass plate coated with a resist layer) through an imaging system to form a circuit pattern of a semiconductor device, a liquid crystal display device, or the like. In such an exposure apparatus, a stage device is provided for placing a mask and a sensitive substrate and precisely moving in one or two dimensions within a plane (XY plane) under position servo control by a laser interferometer.

  The stage apparatus is required to increase the speed (high acceleration) of the stage on which the substrate (mask or sensitive substrate) is placed for the purpose of improving throughput or the like. On the other hand, increasing the speed of the stage tends to increase the amount of heat generated by the drive unit. Such an increase in the amount of heat generation hinders accurate positioning of the stage, such as thermal deformation of the stage and air fluctuation.

  For the purpose of reducing the amount of heat generated due to speeding up, there is a stage device provided with a motor for acceleration / deceleration in addition to a motor used when moving at a constant speed (see, for example, Patent Document 1).

In this stage apparatus, a pair of electromagnets are arranged to face each other so as to sandwich a magnetic body fixed to the stage. When the stage is accelerated or decelerated, a force in the moving direction is applied to the stage by the attractive force of the electromagnet. When moving at a constant speed, the current of the electromagnet is controlled to zero. Then, the stage is driven in a non-contact and low heat generation by utilizing an attractive force generated between the electromagnet and the magnetic body.
JP 2000-106344 A (FIG. 1)

  Although an electromagnet has an advantage that a large attractive force can be generated with a small amount of heat generation, it is necessary to keep a gap between the electromagnet and a counterpart magnetic body small. In the above prior art, since the magnetic body and the electromagnet are arranged side by side in the moving direction of the stage, it is necessary to drive control that always keeps a small gap between the magnetic body and the electromagnet constant, thereby increasing the speed of the stage and the amount of heat generated. The reduction of was limited.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a stage apparatus that can increase the speed of the stage and suppress heat generation, and an exposure apparatus including the stage apparatus.

  The present invention adopts the following configuration corresponding to FIGS. 1 to 7 shown in the embodiment. (However, the reference numerals in parentheses attached to each element are merely examples of the element and do not limit each element.)

  The stage device of the present invention is separate from the stage (202) movable in a predetermined direction, the first drive device (220, 260, 270) that applies the force in the predetermined direction to the stage, and the first drive device. And a second driving device (230, 240, 250) that applies a force in the predetermined direction to the stage, and the second driving device has two opposing surfaces each substantially parallel to the predetermined direction. The force in the predetermined direction is generated by a magnetic attractive force generated between objects.

  In this stage apparatus, in addition to the first driving apparatus, the stage is applied with a force by a second driving apparatus using a magnetic attraction force, so that the speed of the stage is increased and the amount of heat generation is reduced. Further, in this stage apparatus, since the opposing surfaces of the two objects that generate the magnetic attractive force are substantially parallel to the moving direction of the stage, there are relatively few restrictions on the stage movement, and the drive control can be simplified. At the same time, it is advantageous for speeding up and reducing heat generation.

  In this case, the magnetic attraction force can be configured to be generated by a magnetic flux substantially orthogonal to the predetermined direction, for example.

  Further, when the stage (202) is moved at a constant speed or positioned, the first driving device (220, 260, 270) is used, and when the stage is accelerated and / or decelerated, the second driving device (230, 240, 250).

  In this case, the magnetic flux existing between the two objects when the stage moves at a constant speed may be configured to be substantially zero.

  In the stage apparatus, the two objects include a magnetic body (242) and an electromagnet (241), and the magnetic body has a plurality of tooth surfaces (243) arranged at a predetermined pitch in the predetermined direction. The electromagnet may have a plurality of tooth surfaces (244) arranged at a multiphasely shifted pitch with respect to the plurality of tooth surfaces of the magnetic body.

  The first driving device (220, 260, 270) may be configured to generate the force in the predetermined direction by Lorentz force.

The exposure apparatus of the present invention has a mask stage (20) that holds a mask (R) and a substrate stage (40) that holds a substrate (W), and exposes the pattern formed on the mask onto the substrate. An exposure apparatus (EX) that performs the above-described stage apparatus is used for at least one of the mask stage and the substrate stage.
In another exposure apparatus of the present invention, the exposure apparatus (EX) forms a predetermined pattern on a substrate (W) held on a substrate stage (40), and the stage apparatus is used for the substrate stage. It is characterized by that.

  The device manufacturing method of the present invention includes a lithography step of forming a predetermined pattern on an object using the above exposure apparatus (EX).

  According to the stage apparatus of the present invention, it is possible to reliably achieve an increase in the speed of the stage and a reduction in the amount of heat generation.

  According to the exposure apparatus and the device manufacturing method of the present invention, the throughput can be improved by increasing the speed of the stage apparatus.

  Embodiments of a stage apparatus, an exposure apparatus, and a device manufacturing method according to the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of the exposure apparatus EX of the present invention.
The exposure apparatus EX moves a reticle (mask) R and a wafer (substrate) W synchronously in a one-dimensional direction, and applies a pattern PA formed on the reticle R to each shot area on the wafer W via the projection optical system 30. This is a step-and-scan type scanning exposure apparatus, that is, a so-called scanning stepper.
The exposure apparatus EX includes an illumination optical system 10 that illuminates the reticle R with the exposure light EL, a reticle stage 20 that holds the reticle R, and a projection optical system 30 that projects the exposure light EL emitted from the reticle R onto the wafer W. , A wafer stage 40 for holding the wafer W, a control device 50 for comprehensively controlling the exposure apparatus EX, and the like.
Each of these devices is supported on the main body frame 100 or the base frame 150 via the vibration isolation units 60, 70 and the like.
In the following description, the direction that coincides with the optical axis AX of the projection optical system 30 is the Z-axis direction, and the synchronous movement direction (scanning direction) between the reticle R and the wafer W in the plane perpendicular to the Z-axis direction is the Y-axis. The direction perpendicular to the direction, the Z-axis direction, and the Y-axis direction (non-scanning direction) is taken as the X-axis direction. Further, the directions around the X, Y, and Z axes are the θX, θY, and θZ directions, respectively.

The illumination optical system 10 illuminates the reticle R supported by the reticle stage 20 with the exposure light EL, an exposure light source 5, an optical integrator that equalizes the illuminance of the light beam emitted from the exposure light source 5, It has a condenser lens for condensing the exposure light EL from the optical integrator, a relay lens system, a variable field stop for setting the illumination area on the reticle R by the exposure light EL in a slit shape (not shown).
The exposure light EL emitted from the illumination optical system 10 includes far ultraviolet light (DUV) such as ultraviolet emission lines (g-line, h-line, i-line), KrF excimer laser light (wavelength 248 nm) emitted from a mercury lamp. Light) and vacuum ultraviolet light (VUV light) such as ArF excimer laser light (wavelength 193 nm).
The laser beam emitted from the light source 5 is incident on the illumination optical system 10, and the cross-sectional shape of the laser beam is shaped into a slit shape or a rectangular shape (polygon), and the illumination light (exposure) has a substantially uniform illuminance distribution. Light) EL is irradiated onto the reticle R.
The illumination optical system 10 is supported by an illumination system support member 12 fixed to the upper surface of the second support plate 120 that constitutes the main body frame 100.

The reticle stage (mask stage) 20 supports the reticle R and performs two-dimensional movement in the plane perpendicular to the optical axis AX of the projection optical system 30, that is, the XY plane, and minute rotation in the θZ direction. A reticle fine movement stage that holds the reticle R, a reticle coarse movement stage that moves together with the reticle fine movement stage in the Y-axis direction, which is the scanning direction, with a predetermined stroke, a linear motor that moves these, and the like (see FIG. 2). . The reticle fine movement stage is formed with a rectangular opening, and the reticle is held by vacuum suction or the like by a reticle suction mechanism provided around the opening.
A movable mirror 21 is provided on the reticle stage 20. A laser interferometer 22 is provided at a position facing the moving mirror 21. Then, the position and rotation angle of the reticle R on the reticle stage 20 in the two-dimensional direction are measured in real time by the laser interferometer 22, and the measurement result is output to the control device 50. Then, the control device 50 drives a linear motor or the like based on the measurement result of the laser interferometer 22, thereby positioning the reticle R supported by the reticle stage 20.
The reticle stage 20 is levitated and supported on the upper surface of the second support plate 120 constituting the main body frame 100 via a non-contact bearing (not shown) (for example, a hydrostatic bearing).

The projection optical system 30 projects and exposes the pattern PA of the reticle R onto the wafer W at a predetermined projection magnification β, and includes a plurality of optical elements including an optical element 32 provided at the tip (lower end) portion on the wafer W side. These optical elements are supported by a lens barrel 31. In the present embodiment, the projection optical system 30 is a reduction system having a projection magnification β of, for example, 1/4 or 1/5. Note that the projection optical system 30 may be either an equal magnification system or an enlargement system.
A flange 33 is provided on the outer wall of the lens barrel 31, and is inserted into a cylindrical sensor support frame 35 having a flange. Further, the lens barrel 31 and the sensor support frame 35 are inserted and supported in a hole 113 provided in the first support plate 110 constituting the main body frame 100. The first support board 110 is supported substantially horizontally on the base frame 150 via the vibration isolation unit 60.
The sensor support base 35 is a member that supports sensors such as an autofocus sensor. Further, a kinematic mount (not shown) is provided between the first support board 110 and the sensor support frame 35, and the tilt angle of the projection optical system 30 can be adjusted.

The wafer stage (substrate stage) 40 supports the wafer W and performs two-dimensional movement in the XY plane and minute rotation in the θZ direction. The wafer holder 41 that holds the wafer W, leveling and focusing of the wafer W In order to perform this, the wafer holder 41 is finely driven in three degrees of freedom in the Z-axis direction, θX direction, and θY direction, the XY table 43 that positions the Z table 42 in the X direction and the Y direction, and the XY table 43. Includes a base plate (coarse movement stage) 301 that moves the base plate 301 in the X axis, Y axis, and θz directions, a wafer surface plate 44 that supports the base plate 301 so as to be movable in the XY plane, and the like. The XY table 43 functions as a fine movement stage with respect to the base plate 301 functioning as a coarse movement stage.
A movable mirror 47 is provided on the Z table 42, and a laser interferometer (position measuring unit) 48 is provided at a position facing the movable mirror 47. The two-dimensional position and rotation angle of the wafer W on the wafer stage 40 are measured in real time by the laser interferometer 48, and the measurement result is output to the control device 50. Then, the controller 50 positions the wafer W supported on the wafer stage 40 by driving a linear motor or the like based on the measurement result of the laser interferometer 48.
A plurality of air pads 45, which are non-contact bearings, are fixed to the bottom surface of the base plate 301, and the XY table 43 is levitated and supported on the wafer surface plate 44 by a clearance of about several microns, for example, by these air pads 45. The Further, the wafer surface plate 44 is supported substantially horizontally on the support plate 160 of the basic frame 150 via the vibration isolation unit 70.

The main body frame 100 includes a first support plate 110 that supports the projection optical system 30, a second support plate 120 that supports the reticle stage 20 disposed above the projection optical system 30, the first support plate 110, and the first support plate 110. 2 It is comprised from several support | pillar 130 standingly arranged between the support boards 120. FIG. As described above, the first support plate 110 is formed with the hole 113 formed to be slightly larger than the outer diameter of the cylindrical projection optical system 30. In addition, the 1st support board 110 or the 2nd support board 120, and the some support | pillar 130 are good also as a structure connected with a fastening means etc., and good also as a structure which formed these integrally.
As described above, the main body frame 100 is supported on the base frame 150 via the vibration isolation unit 60.

The base frame 150 has a support plate 160 that supports the wafer stage 40 via the vibration isolation unit 70 on its upper surface, and a plurality of frames that stand on the support plate 160 and support the main body frame 100 via the vibration isolation unit 60. It is comprised from the support | pillar 170. FIG. The support board 160 and the support column 170 may be structured to be connected by fastening means or the like, or may be a structure formed integrally.
And the foundation frame 150 is installed substantially horizontally via the foot | leg part 165 on the floor surface of a clean room.

The control device 50 controls the exposure apparatus EX in an integrated manner, and includes a calculation unit that performs various calculations and controls, a storage unit that records various types of information, an input / output unit, and the like.
Then, for example, an exposure operation for controlling the positions of the reticle R and the wafer W based on the detection results of the laser interferometers 22 and 48 and transferring an image of the pattern PA formed on the reticle R to a shot area on the wafer W. Repeat.

FIG. 2 is a schematic perspective view showing the reticle stage 20.
As shown in FIG. 2, reticle stage 20 includes reticle coarse movement stage 201 provided on reticle surface plate 203, reticle fine movement stage 202 provided on reticle coarse movement stage 201, and reticle surface plate 203. A coarse movement stage 201 is provided on the upper surface of a pair of Y linear motors 210 and 210 capable of moving the coarse movement stage 201 in the Y-axis direction with a predetermined stroke and an upper protrusion 203b at the center of the reticle surface plate 203 and moves in the Y-axis direction. A pair of Y guide portions 215 and 215 for guiding the moving stage 201, an X voice coil motor 220 and a pair of Y voice coils for finely moving the fine moving stage 202 in the X axis, Y axis, and θZ directions on the coarse moving stage 201 Auxiliary motors 230, 240, 25 for assisting the movement of the motors 260, 270 and the fine movement stage 202 It has a like. In FIG. 1, the coarse movement stage 201 and the fine movement stage 202 are simplified and shown as one stage.

  Each of the Y linear motors 210 is provided corresponding to a pair of stators 211 formed of a coil unit (armature unit) provided on the reticle surface plate 203 so as to extend in the Y-axis direction. And a mover 212 made of a magnet unit fixed to the coarse movement stage 201 via a connecting member 213. The stator 211 and the mover 212 constitute a moving magnet type linear motor 210. The mover 212 is driven by electromagnetic interaction with the stator 211, whereby the coarse motion stage 201 (reticle) is driven. The stage 20) moves in the Y-axis direction. Each of the stators 211 is levitated and supported with respect to the reticle surface plate 203 by a plurality of air bearings 214 which are non-contact bearings. For this reason, the stator 211 moves in the −Y direction according to the movement of the coarse movement stage 201 in the + Y direction according to the law of conservation of momentum. The movement of the stator 211 cancels the reaction force accompanying the movement of the coarse movement stage 201 and can prevent the change in the position of the center of gravity.

  Each of the Y guide portions 215 guides the coarse movement stage 201 that moves in the Y-axis direction, and extends in the Y-axis direction on the upper surface of the upper protruding portion 203b formed at the center of the reticle surface plate 203. It is fixed to. An air bearing (not shown) that is a non-contact bearing is provided between the coarse movement stage 201 and the Y guide portions 215 and 215, and the coarse movement stage 201 is supported in a non-contact manner with respect to the Y guide portion 215. Has been.

  Fine movement stage 202 sucks and holds reticle R via a vacuum chuck (not shown). A pair of Y moving mirrors 21a and 21b made of a corner cube is fixed to the end of the fine movement stage 202 in the -Y direction, and an X movement made of a plane mirror extending in the Y axis direction is attached to the end of the fine movement stage 202 in the + X direction. The mirror 21c is fixed. Then, the three laser interferometers 22 (see FIG. 1) that irradiate the measuring beams to the movable mirrors 21a, 21b, and 21c measure the distances from the respective movable mirrors, whereby the X axis of the fine movement stage 202, The Y axis and the position in the θZ direction are detected with high accuracy. Based on the detection result of the laser interferometer 22 (see FIG. 1), the control device 50 (see FIG. 1) performs the Y linear motor 210, the X voice coil motor 220, the Y voice coil motors 260 and 270, and the auxiliary motors 230 and 240. , 250 are driven, and position control (and / or speed control) of reticle R supported by fine movement stage 202 is performed.

FIG. 3 is an explanatory diagram of the drive system of fine movement stage 202.
As shown in FIG. 3, a voice coil motor (X voice coil motor 220, Y voice coil motor 260, 270) and auxiliary motors 230, 240, 250 are disposed between fine movement stage 202 and coarse movement stage 201. It is arranged. Specifically, an X voice coil motor 220 is disposed on one side of the fine movement stage 202 in the + Y direction, and the auxiliary motor 240 and the auxiliary motor are separately provided on both outer sides (± X direction) of the X voice coil motor 220. 250 is arranged. In addition, Y voice coil motors 260 and 270 are disposed apart from each other on the −X direction side of fine movement stage 202, and auxiliary motor 230 is disposed between Y voice coil motors 260 and 270. Yes.

  The voice coil motor 220 (260, 270) includes a stator 221 (261, 271) including a coil and a mover 222 (262, 272) including a permanent magnet, and generates a Lorentz force when a current flows through the coil. A driving force (thrust) is generated between the coarse movement stage 201 and the fine movement stage 202. The X voice coil motor 220 applies a force in the X direction to the fine movement stage 202 to move the fine movement stage 202 relative to the coarse movement stage 201 in the X direction. Y voice coil motors 260 and 270 move fine movement stage 202 relative to coarse movement stage 201 in the Y direction by applying a force in the Y direction to fine movement stage 202.

  Auxiliary motors 230, 240, 250 include stators 231, 241, 251 fixed to coarse movement stage 201, and movers 232, 242, 252 fixed to fine movement stage 202. Then, a driving force (thrust force) is generated between the coarse movement stage 201 and the fine movement stage 202 by the magnetic attraction force between the stators 231, 241, 251 and the movable elements 232, 242, 252. The auxiliary motors 240 and 250 move the fine movement stage 202 relative to the coarse movement stage 201 in the X direction by applying a force in the X direction to the fine movement stage 202. The auxiliary motor 230 moves the fine movement stage 202 relative to the coarse movement stage 201 in the Y direction by applying a force in the Y direction to the fine movement stage 202.

4 representatively shows the structure of the auxiliary motor 240, and is a cross-sectional view taken along line AA shown in FIG.
As shown in FIG. 4, the mover 242 is made of a magnetic material (ferromagnetic material) having a comb-like cross section, and has a plurality of tooth surfaces 243 arranged at a predetermined pitch in the X direction on the + Z side (upper side), and −Z And a plurality of tooth surfaces 244 arranged at a predetermined pitch in the X direction on the side (lower side). The plurality of tooth surfaces 243 and 244 are all arranged substantially parallel to the XY plane (horizontal plane).

  The stator 241 is composed of an electromagnet in which a coil 246 is wound around each phase of a magnetic body 245 (iron core) having a comb-like cross section. The coil 246 has a three-phase six-pole configuration (U, V, W, U ′, V ′, W ′...) Arranged in groups of three in the X direction, which is the driving direction, and the coil 246 has a three-phase alternating current. Applied. The magnetic body 245 (iron core) includes a plurality of tooth surfaces 247 arranged to face a plurality of tooth surfaces 243 of the mover 242 and a plurality of teeth arranged to face a plurality of tooth surfaces 244 of the mover 242. Surface 248. The plurality of tooth surfaces 247 and 248 are all disposed substantially parallel to the XY plane (horizontal plane). When each coil 246 (and magnetic body 245) of the stator 241 is excited by three-phase alternating current, a magnetic flux in the Z direction is generated in each coil 246 (and magnetic body 245), and along with the change in the magnetic flux. A traveling magnetic field is generated in the X direction.

Each tooth surface 247 (248) of the stator 241 and each tooth surface 243 (244) of the mover 242 are kept in a slight contact with each other in the Z direction, and a plurality of teeth of the stator 241 are maintained. The arrangement pitch in the X direction of the surface 247 (248) and the plurality of tooth surfaces 243 (244) of the mover 242 are shifted in a polyphase manner. When the coil 246 (and the magnetic body 245) of the stator 241 is excited, a magnetic attractive force is generated between the teeth of the stator 241 and the movable element 242. By adjusting the current flowing through the coil 246, the magnetic attractive force can be adjusted. The traveling magnetic field generates a thrust Fx that gives a relative linear motion in the X direction between the teeth of the magnetic body of the mover 242 and the electromagnet (coil and magnetic body) of the stator 241. The direction of the thrust Fx and the like are controlled by the three-phase AC frequency control.
Although the structure of the auxiliary motor 240 has been described here, the same applies to the other auxiliary motors 230 and 250 (see FIG. 3).

  Returning to FIG. 3, in the reticle stage 20, after the coarse movement of the coarse movement stage 201, the fine movement stage 202 is driven with respect to the coarse movement stage 201 by the driving force of the voice coil motors 220, 260, and 270. I do.

  Here, when the fine movement stage 202 is accelerated and / or decelerated in the X direction (including the case of following the acceleration / deceleration of the coarse movement stage 201), the auxiliary motors 240 and 250 are used. The auxiliary motor 230 is used during direction acceleration and / or deceleration. That is, the fine movement stage 202 is accelerated and / or decelerated by the driving force (thrust) by the magnetic attractive force. The magnetic attraction force can obtain a large driving force (thrust) with a smaller ampere return than the Lorentz force of the voice coil motors 220, 260, and 270. Therefore, by using the thrust of the auxiliary motors 230, 240, and 250, the speed of the fine movement stage 202 and the reduction of the heat generation are achieved. When the fine movement stage 202 is accelerated and / or decelerated, the driving force by the voice coil motors 220, 260, and 270 may or may not be used together.

  Further, in this example, the tooth surfaces 243 and 244 (see FIG. 4) of the stator 241 and the tooth surfaces 247 and 248 of the mover 242 which are opposing surfaces of two objects that generate a magnetic attractive force are the fine movement stage 202. Since the movement direction (X direction or Y direction) is substantially parallel, there are relatively few restrictions on the movement of the fine movement stage 202. In other words, in order to obtain a thrust using the magnetic attraction force, it is necessary to keep the gap between the two objects that generate the magnetic attraction force small, and the magnetic body and the electromagnet are moved in the direction of movement of the stage as in the conventional example. Are arranged side by side (the facing surface of the magnetic body and the electromagnet intersects the moving direction of the stage), the movable range of the magnetic body relative to the electromagnet is limited to the gap, and the drive control is complicated. The acceleration of the stage and the reduction of heat generation are limited. Compared to this, in the embodiment in which the opposing surfaces (magnetic tooth surfaces) of the stator 241 and the mover 242 are substantially parallel to the movement direction of the fine movement stage 202 as in this example, even if the fine movement stage 202 moves. The distance between the facing surfaces is kept constant. Therefore, the movable range of the mover 242 (magnetic body) relative to the stator 241 (electromagnet) is wide, the drive control can be simplified, and the speed of the fine movement stage 202 and the reduction in heat generation are more sure. Is envisioned.

  On the other hand, when the fine movement stage 202 is moved at a constant speed or precisely positioned, only the thrust by the voice coil motors 220, 260, and 270 is used, and the coils of the auxiliary motors 230, 240, and 250 are brought into a non-excited state. Since the stators 231, 241, and 251 of the auxiliary motors 230, 240, and 250 do not include permanent magnets, the magnetic flux that is present in the stators 231, 241, and 251 of the auxiliary motors 230, 240, and 250 due to the non-excited state is It becomes zero. As a result, the fine movement stage 202 can be positioned with high accuracy by the voice coil motors 220, 260, and 270 without being affected by the auxiliary motors 230, 240, and 250.

FIG. 5 is a schematic plan view showing the wafer stage 40.
As shown in FIG. 5, the base plate 301 (coarse movement stage) is moved in the Y-axis direction (scan direction) and the X-axis direction by the X guide unit 302 and the Y guide unit 303 provided on the wafer surface plate 44. . The XY table 43 is supported on the base plate 301 so as to be movable in the XY directions.

  A voice coil motor (X voice coil motor 320, Y voice coil motors 330 and 340) and auxiliary motors 350 to 370 are disposed between the XY table 43 and the base plate 301. Specifically, an X voice coil motor 320 is disposed on one side of the XY table 43 in the −Y direction, and the auxiliary motor 350 and the auxiliary are separately provided on both outer sides (± X direction) of the X voice coil motor 320. A motor 360 is provided. In addition, two Y voice coil motors 330 and 340 are disposed on one side of the XY table 43 in the −X direction, and an auxiliary motor 370 is disposed between the two Y voice coil motors 330 and 340. Has been.

  Voice coil motors 320, 330, and 340 include stators 321, 331, and 341 including coils, and movers 322, 332, and 342 including permanent magnets. When a current flows through the coils, a Lorentz force is generated, and an XY table. A driving force (thrust force) is generated between 43 and the base plate 301. The voice coil motor 320 moves the XY table 43 relative to the base plate 301 in the X direction by applying a force in the X direction to the XY table 43. The voice coil motors 330 and 340 move the XY table 43 relative to the base plate 301 in the Y direction and the θz direction by applying a force in the Y direction to the XY table 43.

  The auxiliary motors 350, 360, and 370 include stators 351, 361, and 371 that are fixed to the base plate 301 and movers 352, 362, and 372 that are fixed to the XY table 43. A driving force is generated between the base plate 301 and the XY table 43 by the magnetic attraction between the stators 351, 361, 371 and the movers 352, 362, 372. The auxiliary motors 350 and 360 move the XY table 43 in the X direction relative to the base plate 301 by applying a force in the X direction to the XY table 43. The auxiliary motor 370 moves the XY table 43 relative to the base plate 301 in the Y direction by applying a force in the Y direction to the XY table 43.

The structure of the auxiliary motors 350, 360, and 370 is the same as that of the auxiliary motor 240 shown in FIG.
That is, the mover 352 (362, 372) is made of a magnetic material (ferromagnetic material) having a comb-like cross section, and has a plurality of tooth surfaces arranged at a predetermined pitch in the X direction on the + Z side (upper side), and the −Z side. (Lower side) and a plurality of tooth surfaces arranged at a predetermined pitch in the X direction. The plurality of tooth surfaces are all arranged substantially parallel to the XY plane (horizontal plane).
The stator 351 (361, 371) is composed of an electromagnet in which a coil is wound around each phase of a magnetic body (iron core) having a comb-like cross section. Three-phase alternating current is applied to the coil. The magnetic body (iron core) includes a plurality of tooth surfaces arranged to face a plurality of tooth surfaces of the mover 352 (362, 372). The plurality of tooth surfaces are all arranged substantially parallel to the XY plane (horizontal plane). When each coil (and magnetic body) of the stator 351 (361, 371) is excited by three-phase alternating current, a magnetic flux in the Z direction is generated in each coil (and magnetic body), and along with the change in the magnetic flux. A traveling magnetic field is generated in the X direction.

  The tooth surface of the stator 351 (361, 371) and the tooth surface of the movable element 352 (362, 372) are kept in a non-contact state by providing a slight gap in the Z direction, and the stator 351 (361, 371). ) And the plurality of tooth surfaces of the mover 352 (362, 372) are shifted in polyphase. When the coil (and magnetic body) of the stator 351 (361, 371) is excited, a magnetic attractive force is generated between the teeth of the stator 351 (361, 371) and the mover 352 (362, 372). The magnetic attraction force can be adjusted by adjusting the current flowing through the coil. Then, due to the traveling magnetic field, a relative straight line in the X or Y direction between the teeth of the magnetic body of the mover 352 (362, 372) and the electromagnet (coil and magnetic body) of the stator 351 (361, 371). Thrust that gives motion is generated. The direction of this thrust is controlled by the frequency control of the three-phase alternating current.

In the wafer stage 40, after the base plate 301 is coarsely moved, the XY table 43 is driven by the driving force of the voice coil motors 320, 330, and 340 to position the XY table 43.
When the XY table 43 is accelerated and / or decelerated (including the case of following the acceleration / deceleration of the base plate 301), auxiliary motors 350, 360, and 370 are used. That is, the XY table 43 is accelerated and / or decelerated by the thrust generated by the magnetic attractive force. By using the thrust of the auxiliary motors 350 to 370, the XY table 43 can be speeded up and the amount of heat generated can be reduced. Further, since the opposing surfaces (magnetic tooth surfaces) of the stators 351 to 371 and the movers 352 to 372 of the auxiliary motors 350 to 370 are substantially parallel to the moving direction of the XY table 43, the stators 351 to 351 The movable range of the movers 352 to 372 (XY table 43) relative to 371 is wide, and as a result, the drive control is simplified, and the XY table 43 is more reliably increased in speed and reduced in heat generation. Figured. When the XY table 43 is accelerated and / or decelerated, the thrust generated by the voice coil motors 320, 330, and 340 may or may not be used together.

  In addition, when the XY table 43 is moved at a constant speed or precisely positioned, only the thrust generated by the voice coil motors 320, 330, and 340 is used, and the coils of the auxiliary motors 350, 360, and 370 are brought into a non-excited state. Since the stators 351 to 371 of the auxiliary motors 350 to 370 do not include permanent magnets, the magnetic flux existing in the stators 351 to 371 of the auxiliary motors 350 to 370 becomes zero due to the non-excitation state. As a result, the XY table 43 can be positioned with high accuracy by the voice coil motors 320 to 340 without being affected by the auxiliary motors 350 to 370.

  As described above, according to the present embodiment, in each of the reticle stage 20 and the wafer stage 40, the speed of the stage can be increased and the amount of generated heat can be reduced by using the magnetic attractive force. Therefore, it is possible to improve throughput and exposure accuracy.

  As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

  In the above embodiment, the example in which the stage apparatus according to the present invention is applied to both the reticle stage 20 and the wafer stage 40 has been described, but the present invention may be applied to only one of them.

  Further, according to the present invention, as disclosed in JP-A-10-163099, JP-A-10-214783, JP-T 2000-505958, etc., substrates to be processed such as wafers are separately placed. The present invention can also be applied to a twin stage type exposure apparatus having two stages that can move independently in the XY directions.

  When a linear motor (see USP 5,623,853 or USP 5,528,118) is used for reticle stage 20 or wafer stage 40, either an air levitation type using air bearings or a magnetic levitation type using Lorentz force or reactance force is used. Good. Each stage may be a type that moves along a guide, or may be a guideless type that does not have a guide.

As described in JP-A-8-166475 (USP 5,528,118), the reaction force generated by the movement of the wafer stage 40 is not transmitted to the projection optical system 30, and is mechanically floored using a frame member. You may escape to (earth).
As described in JP-A-8-330224 (USP 5,874,820), the reaction force generated by the movement of the reticle stage 20 is not mechanically transmitted to the projection optical system 30 by using a frame member. You may escape to (earth). Further, as described in JP-A-8-63231 (USP 6,255,796), the reaction force may be processed using a momentum conservation law.

  In the above embodiment, the step-and-scan type exposure apparatus has been described as an example. However, the present invention can also be applied to a step-and-repeat type exposure apparatus. The light source provided in the illumination optical system 10 of the exposure apparatus of the present embodiment is not limited to an ultrahigh pressure mercury lamp, KrF excimer laser, ArF excimer laser, or F2 laser (157 nm), but also charged particles such as X-rays and electron beams. Lines can be used. For example, when using an electron beam, thermionic emission type lanthanum hexabolite (LaB6) and tantalum (Ta) can be used as the electron gun.

  Furthermore, a single wavelength laser beam in the infrared region or visible region oscillated from a DFB semiconductor laser or fiber laser as a light source is amplified by, for example, a fiber amplifier doped with erbium (or both erbium and yttrium), and nonlinear optics You may use the harmonic which wavelength-converted into the ultraviolet light using the crystal | crystallization. For example, if the oscillation wavelength of a single wavelength laser is in the range of 1.51 to 1.59 μm, the generated wavelength is in the range of 189 to 199 nm, the eighth harmonic, or the generated wavelength is in the range of 151 to 159 nm. A 10th harmonic is output.

  In particular, when the oscillation wavelength is in the range of 1.544 to 1.553 μm, the 8th harmonic in the range of 193 to 194 nm, that is, ultraviolet light having substantially the same wavelength as the ArF excimer laser light is obtained. When the oscillation wavelength is in the range of 1.57 to 1.58 μm, the tenth harmonic wave in the range of 157 to 158 nm, that is, ultraviolet light having substantially the same wavelength as the F2 laser light is obtained. Further, if the oscillation wavelength is in the range of 1.03 to 1.12 μm, the seventh harmonic whose output wavelength is in the range of 147 to 160 nm is output, and in particular, the oscillation wavelength is in the range of 1.099 to 1.106 μm. If it is inside, the 7th harmonic within the range of 157 to 158 μm, that is, ultraviolet light having substantially the same wavelength as the F2 laser light is obtained. In this case, for example, an yttrium-doped fiber laser can be used as the single wavelength oscillation laser.

  Further, the present invention is not limited to an exposure apparatus used for manufacturing a semiconductor element, but also used for manufacturing a display including a liquid crystal display element (LCD) and the like, an exposure apparatus for transferring a device pattern onto a glass plate, and a thin film magnetic head. The present invention can also be applied to an exposure apparatus that is used for manufacturing and transfers a device pattern onto a ceramic wafer, and an exposure apparatus that is used to manufacture an image sensor such as a CCD. Furthermore, in an exposure apparatus that transfers a circuit pattern to a glass substrate or a silicon wafer in order to manufacture a reticle or mask used in an optical exposure apparatus, EUV exposure apparatus, X-ray exposure apparatus, electron beam exposure apparatus, or the like. The present invention can also be applied. 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, fluorite, 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. Such an exposure apparatus is disclosed in WO99 / 34255, WO99 / 50712, WO99 / 66370, JP-A-11-194479, JP-A2000-12453, JP-A-2000-29202, and the like. .

  Further, for example, as disclosed in JP-A-10-154659, the present invention may be applied to an immersion exposure apparatus that forms an image on a substrate via a liquid on the substrate.

  Further, the stage apparatus of the present invention is not limited to the reticle stage and wafer stage provided in the exposure apparatus, but is also a stage apparatus that moves in a state where an object is placed (not limited to one-dimensional movement or two-dimensional movement). It is possible to apply to the general case when controlling.

  An exposure apparatus to which the present invention is applied assembles various subsystems including the constituent elements recited in the claims of the present application so as to maintain predetermined mechanical accuracy, electrical accuracy, and optical accuracy. It is manufactured by. In order to ensure these various accuracies, before and after assembly, various optical systems are adjusted to achieve optical accuracy, various mechanical systems are adjusted to achieve mechanical accuracy, and various electrical systems are Adjustments are made to achieve electrical accuracy. The assembly process from the various subsystems to the exposure apparatus includes mechanical connection, electrical circuit wiring connection, pneumatic circuit piping connection and the like between the various subsystems. Needless to say, there is an assembly process for each subsystem before the assembly process from the various subsystems to the exposure apparatus. When the assembly process of the various subsystems to the exposure apparatus is completed, comprehensive adjustment is performed to ensure various accuracies as the entire exposure apparatus. The exposure apparatus is preferably manufactured in a clean room in which the temperature, cleanliness, etc. are controlled.

  Next, an embodiment of a microdevice manufacturing method using the above-described exposure apparatus in a lithography process will be described. FIG. 6 is a flowchart showing a manufacturing example of a micro device (a semiconductor chip such as an IC or LSI, a liquid crystal panel, a CCD, a thin film magnetic head, a micro machine, or the like). As shown in FIG. 6, first, in step S10 (design step), a function / performance design (for example, circuit design of a semiconductor device) of a micro device is performed, and a pattern design for realizing the function is performed. Subsequently, in step S11 (mask manufacturing step), a mask (reticle) on which the designed circuit pattern is formed is manufactured. On the other hand, in step S12 (wafer manufacturing step), a wafer is manufactured using a material such as silicon.

  Next, in step S13 (wafer processing step), using the mask and wafer prepared in steps S10 to S12, an actual circuit or the like is formed on the wafer by lithography or the like, as will be described later. Next, in step S14 (device assembly step), device assembly is performed using the wafer processed in step S13. This step S14 includes processes such as a dicing process, a bonding process, and a packaging process (chip encapsulation) as necessary. Finally, in step S15 (inspection step), inspections such as an operation confirmation test and a durability test of the microdevice manufactured in step S14 are performed. After these steps, the microdevice is completed and shipped.

  FIG. 7 is a diagram showing an example of a detailed flow of step S13 of FIG. 7 in the case of a semiconductor device. In FIG. 7, in step S21 (oxidation step), the surface of the wafer is oxidized. In step S22 (CVD step), an insulating film is formed on the wafer surface. In step S23 (electrode formation step), an electrode is formed on the wafer by vapor deposition. In step S24 (ion implantation step), ions are implanted into the wafer. Each of the above steps S21 to S24 constitutes a pre-processing process at each stage of the wafer processing, and is selected and executed according to a necessary process at each stage.

  At each stage of the wafer process, when the above pre-process is completed, the post-process is executed as follows. In this post-processing process, first, in step S25 (resist formation step), a photosensitive agent is applied to the wafer. Subsequently, in step S26 (exposure step), the circuit pattern of the mask is transferred to the wafer by the lithography system (exposure apparatus) and the exposure method described above. Next, in step S27 (development step), the exposed wafer is developed, and in step S28 (etching step), exposed members other than the portion where the resist remains are removed by etching. In step S29 (resist removal step), the resist that has become unnecessary after the etching is removed. By repeatedly performing these pre-processing steps and post-processing steps, multiple circuit patterns are formed on the wafer.

It is a schematic block diagram which shows one Embodiment of the exposure apparatus of this invention. It is a schematic perspective view which shows a reticle stage. It is explanatory drawing of the drive system of a reticle fine movement stage. FIG. 4 is a cross-sectional view taken along line AA shown in FIG. 3, representatively showing the structure of the auxiliary motor. It is a schematic plan view which shows a wafer stage. It is a flowchart which shows an example of the manufacturing process of a microdevice. It is a figure which shows an example of the detailed flow of step S13 of FIG. 6 in the case of a semiconductor device.

Explanation of symbols

  EX ... exposure apparatus, R ... reticle (mask), W ... wafer (substrate), 20 ... reticle stage (mask stage), 30 ... projection optical system, 40 ... wafer stage, 41 ... wafer holder, 42 ... Z table, 43 ... XY table, 44 ... wafer surface plate, 50 ... control device, 201 ... reticle coarse movement stage, 202 ... reticle fine movement stage, 203 ... reticle surface plate, 210 ... Y linear motor, 211, 221, 231, 241, 251, 261 , 271, 321, 331, 341, 351, 361, 371 ... stator, 212, 222, 232, 242, 252, 262, 272, 322, 332, 342, 352, 362, 372 ... mover, 220 ... X Voice coil motor (first driving device), 260, 270... Y voice coil motor (first driving device), 2 0, 240, 250, 350, 360, 370 ... auxiliary motor (second drive device), 243, 244 ... tooth surface (opposing surface), 245 ... magnetic body, 246 ... coil, 301 ... base plate, 302 ... X guide part , 303... Y guide section, 320, 330, 340... Voice coil motor (first driving device).

Claims (9)

A stage movable in a predetermined direction;
A first driving device for applying a force in the predetermined direction to the stage;
A second drive device provided separately from the first drive device, and applying a force in the predetermined direction to the stage;
The stage device characterized in that the second driving device generates a force in the predetermined direction by a magnetic attraction force generated between two objects each having an opposing surface substantially parallel to the predetermined direction.   The stage apparatus according to claim 1, wherein the magnetic attractive force is generated by a magnetic flux substantially orthogonal to the predetermined direction. When moving the stage at a constant speed or positioning, using the first driving device,
The stage device according to claim 1 or 2, wherein the second driving device is used when the stage is accelerated and / or decelerated.   The stage apparatus according to claim 3, wherein a magnetic flux existing between the two objects at the time of positioning the stage is substantially zero. The two objects include a magnetic body and an electromagnet,
The magnetic body has a plurality of tooth surfaces arranged at a predetermined pitch in the predetermined direction,
The stage according to any one of claims 1 to 4, wherein the electromagnet has a plurality of tooth surfaces arranged at a pitch shifted in a polyphase manner with respect to the plurality of tooth surfaces of the magnetic body. apparatus.   The stage device according to claim 1, wherein the first driving device generates a force in the predetermined direction by a Lorentz force. An exposure apparatus having a mask stage for holding a mask and a substrate stage for holding a substrate, and exposing the pattern formed on the mask onto the substrate,
An exposure apparatus using the stage apparatus according to any one of claims 1 to 6 as at least one of the mask stage and the substrate stage. An exposure apparatus that forms a predetermined pattern on a substrate held on a substrate stage,
An exposure apparatus using the stage apparatus according to any one of claims 1 to 6 as the substrate stage. A device manufacturing method including a lithography process, wherein the exposure apparatus according to claim 7 or 8 is used in the lithography process.

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