JP3555183B2 - Stage device and exposure device - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a stage device provided with switch means for limiting a moving range of a moving table on which a positioning target is placed, and in particular, a step-and-scan type exposure apparatus for manufacturing a semiconductor device or the like. It is suitable to be applied to a reticle stage or a wafer stage.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, when a semiconductor element, a liquid crystal display element, or the like is manufactured by using a photolithography technique, a pattern formed on a reticle (or a photomask or the like) is coated with a photoresist through a projection optical system. A projection exposure apparatus for exposing a wafer (or a glass plate or the like) is used.
[0003]
In recent years, since one chip pattern such as a semiconductor element has been increasing in size, a projection exposure apparatus for exposing a pattern having a larger area on a reticle onto a wafer has been required. If the demand for such an increase in the exposure area is satisfied by a so-called step-and-repeat type projection exposure apparatus that collectively exposes the pattern on the entire surface of the reticle, the projection optical system needs to be directly increased in size. A projection optical system having high imaging performance over the entire exposure field has a disadvantage of high manufacturing cost.
[0004]
Then, after moving each shot area of the wafer to the scanning start position, in synchronization with scanning the reticle in a direction transverse to the optical axis of the projection optical system while illuminating the reticle, the wafer is moved to the projection optical system. Attention has been paid to a scanning exposure apparatus such as a so-called step-and-scan method that exposes a reticle pattern to each shot area of a wafer by scanning in a direction crossing the optical axis.
[0005]
FIG. 10 shows a schematic configuration of a conventional scanning type exposure apparatus. In FIG. 10, illumination light IL from an optical integrator (not shown) in the illumination optical system is transmitted through a first relay lens 1 to a field stop. Illuminate 2. Illumination light passing through the slit-shaped opening of the field stop 2 uniformly passes through the slit-shaped illumination area 7 on the reticle 6 via the second relay lens 3, the mirror 4 for bending the optical path, and the illumination condenser lens 5. Illuminate with illuminance. The arrangement surface of the field stop 2 and the pattern forming surface of the reticle 6 are conjugate, and the width d of the field stop 2 in the short side direction is formed._SThe projected image of the rectangular opening is a slit-shaped illumination area 7.
[0006]
The pattern image in the illumination area 7 of the reticle 6 is image-formed and projected into the slit-shaped exposure area 18 on the wafer 17 via the both-side telecentric (or one-side telecentric) projection optical system 14. Here, the Z axis is taken parallel to the optical axis of the projection optical system 14, the X axis is taken perpendicular to the plane of FIG. 10 in a plane perpendicular to the Z axis, and the Y axis is taken parallel to the plane of FIG. The direction parallel to the Y axis is the scanning direction.
[0007]
At this time, the reticle 6 is held on the fine movement stage 8, the fine movement stage 8 is mounted on the scanning stage 9 so as to be movable and rotatable in the XY plane, and the scanning stage 9 is not shown on the reticle base 10. Is mounted so as to be driven in the Y direction (or the −Y direction) which is the scanning direction by the linear motor. Coordinates in the scanning direction and the non-scanning direction of the fine movement stage 8 measured by the movable mirror 11 fixed to the end on the fine movement stage 8 and the laser interferometer 12 installed outside are supplied to the main control system 13. . The main control system 13 controls the position of the fine movement stage 8, the scanning speed of the scanning stage 9, and the like based on the supplied coordinates.
[0008]
On the other hand, the wafer 17 is mounted on an X stage 20 via a wafer holder 19, and the X stage 20 is mounted on a Y stage 21 so as to be freely driven in the X direction by a driving motor 27. It is mounted on the device base 22 so as to be freely driven in the Y direction by a drive motor 25 and a feed screw 26. On the X stage 20, a Z stage for adjusting the position of the wafer 17 in the Z direction, a leveling stage for adjusting the tilt angle of the wafer 17, and the like (not shown) are mounted. Further, the two-dimensional coordinates of the X stage 20 measured by the movable mirror 23 fixed on the X stage 20 and the laser interferometer 24 installed outside are supplied to the main control system 13. The operation of the drive motors 25 and 27 and the like is controlled based on the coordinates thus set.
[0009]
At the time of scan exposure, assuming that the projection magnification of the projection optical system 14 is β, under the control of the main control system 12, the scanning stage 9 on the reticle side moves, for example, in the B1 direction at a speed V._RThe Y stage 21 on the wafer side is moved in the C1 direction at a speed V_W(= Β · V_R), The pattern image of the reticle 6 is sequentially projected and exposed on the wafer 17.
[0010]
FIG. 11 is a perspective view showing a state of the synchronous scanning. In FIG. 11, the pattern area 15 of the reticle 6 is scanned in the B1 direction with respect to the hatched slit-like illumination area 7 in FIG. Then, the shot area 16 of the wafer 17 is scanned in the C1 direction with respect to the hatched exposure area 18. Thus, the pattern image in the pattern area 15 of the reticle 6 is sequentially exposed on the shot area 16.
[0011]
FIG. 12 is a plan view of the reticle stage in FIG. 10, and FIG. 13 is a side view of the reticle stage. As shown in FIG. 12, the scanning stage 9 is a linear guide parallel to the Y axis on the reticle base 10. It is placed movably in the Y direction along 34A and 34B. Further, a first linear motor 31A is constituted by the stator 33A and the mover 32A, and a second linear motor 31B is constituted by the stator 33B and the mover 32B. The stators 33A and 33B are fixed on the reticle base 10 in parallel with the linear guides 34A and 34B, and the movers 32A and 32B are fixed to the scanning stage 9 along the stators 33A and 33B. The scanning stage 9 is driven in the + Y direction or the −Y direction with respect to the reticle base 10 by these two linear motors 31A and 31B.
[0012]
Further, a pair of micro switches 36A and 36B as limit switches are fixed along the linear guide 34A so as to sandwich the scanning stage 9 on the reticle base 10. Plates 35A and 35B are attached. In this case, drive power is supplied to the linear motors 31A and 31B with the two micro switches 36A and 36B open. Then, as shown in FIG. 13, when the scanning stage 9 moves in the -Y direction and the operation plate 35A comes into contact with the micro switch 36A and closes the micro switch 36A, the driving power to the linear motors 31A and 31B is cut off. The scanning stage 9 stops with the microswitch 36A closed. Thereafter, in order to supply the driving power to the linear motors 31A and 31B again, the scanning stage 9 is manually pushed back to the movable range in the + Y direction (the range in which the driving power is supplied to the linear motors 31A and 31B), and the micro switch is turned on. 36A had to be open.
[0013]
Similarly, when the scanning stage 9 moves in the + Y direction and the operation plate 35B comes into contact with the micro switch 36B to close the micro switch 36B, the driving power to the linear motors 31A and 31B is cut off, and the linear motors 31A and 31B are again turned on. In order to supply the driving power to the scanning stage, it was necessary to manually push the scanning stage 9 back to the movable range in the −Y direction.
[0014]
[Problems to be solved by the invention]
As described above, in the conventional reticle stage, the movable range of the scanning stage 9 is set by the micro switches 36A and 36B, and after the micro switches 36A and 36B are closed, the scanning stage 9 is returned to the movable range again. Requires manual pushing of the scanning stage 9 back into the movable range. Therefore, for example, when the scanning stage 9 goes out of the movable range during the exposure process, it is necessary to open the chamber in which the exposure apparatus is housed, interrupt the exposure process, and manually move the scanning stage 9. Was. In this case, the temperature inside the exposure apparatus changes due to opening and closing of the chamber, and it is necessary to interrupt the exposure process until the temperature is stabilized, so that the throughput (productivity) of the exposure process is disadvantageously reduced. Was.
[0015]
Similarly, in a scanning type exposure apparatus such as a wafer stage or a general batch exposure type exposure apparatus (stepper or the like), the movable range of the stage is limited by a microswitch. In the case where a configuration in which the driving power to the driving device is cut off by the microswitch is adopted, it is necessary to manually push the stage back into the movable range, so that there is a disadvantage that the throughput of the exposure process is reduced. .
[0016]
In view of the above, the present invention moves a moving table by a driving device along a predetermined base and cuts off driving power for the driving device when the moving table exceeds a predetermined allowable moving range. In such a stage device, it is preferable that the moving table can be automatically returned to within the allowable moving range when the moving power of the driving device is cut off because the moving table exceeds the allowable moving range.FirstAim.
It is a second object of the present invention to provide an exposure apparatus having the above-mentioned moving table and which does not reduce the productivity of the exposure step.
[0017]
[Means for Solving the Problems]
A stage device according to the present invention includes a moving table (9) on which a positioning object (6, 8) is mounted, a base (10) on which the moving table is movably mounted in a predetermined direction, and a base (10). To move the moving table (9) in the predetermined direction.Electromagnetic drive(31A), when the moving table (9) exceeds the allowable moving range in the predetermined direction with respect to the base (10).Electromagnetic drive(31A)Cut off the drive current circuit toSwitch means (50), and push-back means (46-48) for generating an urging force for pushing the moving table (9) back to its allowable movement range side earlier than the actuation of the switch means;When the moving table (9) moves beyond the allowable movement range against the urging force, the occurrence of an error is notified and the supply of the driving current is stopped in response to the interruption of the driving current circuit by the switch means (50). And a drive system that resumes the supply of drive current when the error is recovered.It is provided with.
[0018]
in this case,ThatThe urging force of the push-back means (46-48) is larger than the frictional force between the moving table (9) and the base (10), andElectromagnetic drive(31A)Driving forceDesirably smaller.
An example of the push-back means has an elastic member (47, 48).
[0019]
Furthermore, theElectromagnetic driveOne example of (31A) is a linear motor.
It is desirable to provide a frame (44) for supporting the push-back means (46-48) and the switch means (50).
Further, the exposure apparatus according to the present invention includes a reticle stage (8, 9) that can move by mounting a reticle (6) and a wafer stage (19 to 21) that can hold and move a wafer (17). In the exposure apparatus, the stage apparatus of the present invention is used for at least one of the reticle stage (8, 9) and the wafer stage (19 to 21).
[0020]
[Action]
According to the present invention, when the moving table (9) runs away from the permissible moving range and approaches the switch means (50), for example, the push-back means (46-48) first moves the moving table (9) against the moving table (9). The bias to the allowable movement range side is started. Further, when the moving table (9) moves, the switch means (50) is activated.Electromagnetic driveThe operation of (31A) stops. That is,Electromagnetic driveThe driving force on the moving table (9) by (31A) disappears, and the moving table (9) stops.
[0021]
Even in this state, the push-back means (46-48) are in operation, and the push-back means (46-48) have an urging force exceeding the frictional force between the moving table (9) and the base (10). The moving table (8) is pushed back to the allowable moving range side. Then, the switch means (50) is in a non-operating state,Electromagnetic driveThe drive of the moving table (9) by (31A) becomes possible. However, when the switch means (50) is activated, for example,Electromagnetic driveThe drive system of (31A) shifts to the error sequence, and after the error processing ends,Electromagnetic driveBy performing the driving of (31A), it is possible to prevent the moving stage (9) from running out of control toward the switch means (50) again.
[0022]
Next, when the push-back means has an elastic member such as a coil spring or rubber, a biasing force can be generated by the elastic member with a simple configuration without adding a power source or the like.
Also,Electromagnetic driveHowever, in the case of a linear motor, when the switch means (50) is operated and the supply of the driving power to the linear motor is cut off, the linear motor has no driving force at all. Therefore, only the frictional force and the urging force from the push-back means (46 to 48) act on the movable table (9), and the movable table (9) is easily returned to the allowable movement range side.
[0023]
【Example】
Hereinafter, an embodiment of a stage device according to the present invention will be described with reference to FIGS. In the present embodiment, the present invention is applied to a reticle height of a step-and-scan type projection exposure apparatus. In FIGS. 1 and 2, portions corresponding to FIGS. The detailed description is omitted.
[0024]
FIG. 1 is a plan view of a reticle stage according to the present embodiment. In FIG. 1, a scanning stage 9 is slidably mounted in a Y direction along linear guides 34A and 34B on a base 10, and a scanning stage 9 is provided. Is driven in the + Y direction or the −Y direction with respect to the base 10 by the linear motors 31A and 31B. A sliding portion 9a (see FIG. 2) is formed at the bottom of the scanning stage 9 so as to face one of the linear guides 34A, and a sliding portion 9b (see FIG. 5) so as to face the other linear guide 34B. A bearing 60 (see FIG. 5) is formed between the linear guides 34A and 34B and the sliding portions 9a and 9b.
[0025]
The fine movement stage 8 is mounted on the scanning stage 9 so as to be finely movable in the X direction, the Y direction, and the rotation direction (θ direction), and the reticle 6 on which the original pattern is formed is held on the fine movement stage 8 by vacuum suction or the like. Have been. Illumination light for exposure is illuminated from an illumination optical system (not shown) onto a slit-shaped illumination area 7 in a pattern formation area on the lower surface of the reticle 6, and during scanning exposure, a + Y direction (or -Y) which is a short direction of the illumination area 7 is used. The reticle 6 is scanned at a predetermined speed via the scanning stage 9 in the direction (direction), and the position is adjusted by the fine movement stage 8 as necessary.
[0026]
A moving mirror 11Y for the Y axis is fixed to the end of the fine movement stage 8 in the Y direction, and a laser beam is irradiated on the moving mirror 11Y from two external laser interferometers 12YB and 12YA in parallel with the Y axis. Have been. The Y coordinate of fine movement stage 8 is obtained from the average value of the measurement values of laser interferometers 12YB and 12YA, and the rotation angle of fine movement stage 8 is obtained from the difference between the measurement values of laser interferometers 12YB and 12YA. A moving mirror 11X for the X axis is fixed to an end of the fine movement stage 8 in the X direction, and a laser beam is irradiated on the moving mirror 11X from an external laser interferometer 12X in parallel with the X axis. The X coordinate of the fine movement stage 8 is obtained from the measurement value of the laser interferometer 12X, and the position in the Y direction of the scanning stage 9 and the scanning speed are determined based on the X coordinate, the Y coordinate, and the rotation angle thus measured. The position and the rotation angle of the fine movement stage 8 are controlled in parallel.
[0027]
Next, a reference plate 42 is fixed to a side surface of the scanning stage 9 in the X direction, and an origin sensor 43 is fixed to a position on the base 10 where the reference plate 9 passes. FIG. 5 shows the positional relationship between the reference plate 42 and the origin sensor 43. In FIG. 5, the origin sensor 43 includes a light emitting unit and a light receiving unit. When the light passes in the Y direction, an origin signal is generated from the light receiving portion. In this embodiment, the measurement values of the laser interferometers 12YA and 12YB are reset using the origin signal at the start of use of the reticle stage, for example.
[0028]
Returning to FIG. 1, a pair of limit switch units 41A and 41B are fixed on the base 10 so as to sandwich the scanning stage 9 in the Y direction.
FIG. 2 is a front view of FIG. 1. As shown in FIG. 2, when the scanning stage 9 moves in the −Y direction or the + Y direction, the bottom of the scanning stage 9 contacts the limit switch unit 41A or 41B. Thus, the drive power to the linear motors 31A and 31B is cut off as described later. That is, the allowable movement range of the scanning stage 9 in the Y direction is defined by the limit switch unit 41A or 41B.
[0029]
FIG. 3 is an enlarged plan view of one of the limit switch units 41A in FIG. 1, and FIG. 4A is an enlarged front view thereof. In the limit switch unit 41A shown in FIGS. 3 and 4A, a YZ plane is shown. A linear guide 45 is formed in a U-shaped frame 44 parallel to the Y direction. A movable member 46 is slidably mounted along the linear guide 45, and tension coil springs 47 are respectively provided between the convex portions 46 a and 46 b on both side surfaces of the movable member 46 and the side wall 44 a in the + Y direction of the frame 44. And the movable member 46 is pressed against the side wall 44a by the tension coil springs 47 and 48. The total urging force of the tension coil springs 47 and 48 when the mover 46 is in contact with the side wall 44a is larger than the frictional force between the scanning stage 9 and the base 10, and the linear motors 31A and 31B The driving force is set to be smaller than the average driving force.
[0030]
An operation plate 49 is fixed to a side surface of the mover 46, and a micro switch 50 is fixed on the frame 44 at a position where the operation plate 49 passes. Two circuits are arranged in parallel in the microswitch 50, and these two circuits are individually connected between one cable for supplying the drive current of the linear motors 31A and 31B in FIG. When the micro switch 50 comes into contact with the operation plate 49 and closes, the micro switch 50 is activated and the circuit inside is turned off, and the supply of the drive current to the linear motors 31A and 31B is cut off. The microswitch 50 is in a non-operating state when the operating plate 49 is apart and opened, and the circuit inside is turned on, so that the linear motors 31A and 31B are driven. The other limit switch unit 41B in FIG. 1 has a structure symmetrical to the limit switch unit 41A in FIG.
[0031]
Next, the operation of this embodiment will be described. First, in FIG. 4A, an area in the Y direction sandwiched between the mover 46 and the mover of the other limit switch unit 41B (see FIG. 1) is defined as an allowable movement range 51. At this time, for example, when the scanning stage 9 moves in the direction of the arrow 52 (−Y direction) due to runaway of the linear motors 31A and 31B in FIG. 1 and moves out of the allowable movement range 51, the scanning stage 9 pushes the movable element 46. start. Thereafter, as shown in FIG. 4B, the movable member 46 is pushed by the scanning stage 9 and moves in the −Y direction along the linear guide 45, and the operation plate 49 fixed to the movable member 46 is eventually moved to the micro position. The switch 50 is closed. In this state, the supply of the driving current to the linear motors 31A and 31B in FIG. 1 is cut off, and the driving force of the scanning stage 9 disappears. In this case, since the tension coil springs 47 and 48 have a sufficient biasing force F in the + Y direction to push back the scanning stage 9, the mover 46 pushes the scanning stage 9 back in the + Y direction, and the microswitch 50 When opened, the drive current can be supplied to the linear motors 31A and 31B.
[0032]
However, in this embodiment, when the microswitch 50 is closed and the drive current is cut off, the drive system for the linear motors 31A and 31B (not shown) sets the drive current to The occurrence of an error is notified to the illustrated host computer or the like. After that, when the error recovery is performed, the supply of the drive current to the linear motors 31A and 31B is started, so that the movable stage 46 returns the scanning stage 9 to the allowable movement range 51.
[0033]
Further, since there is a possibility that the measured values of the laser interferometers 12YA and 12YB in FIG. 1 may be erroneous due to, for example, runaway or the like, the linear motors 31A. 31B is driven to move the scanning stage 9 in the −Y direction so that the reference plate 42 crosses the origin sensor 43. Then, the measurement values of the laser interferometers 12YA and 12YB are reset using the origin signal obtained from the origin sensor 43 at that time. Thus, the Y coordinate is always accurately measured on the scanning stage 9.
[0034]
As described above, according to the present embodiment, after the micro switch 50 is closed and the drive current to the linear motors 31A and 31B is cut off, the movable element 46 as the push-back means moves the scanning stage 9 within the allowable movement range 51. Since the scanning stage 9 is pushed back, there is no need for the operator to manually push the scanning stage 9 back. Therefore, the exposure process of the scanning exposure apparatus using the reticle stage shown in FIG. 1 is not interrupted for a long time, and the throughput of the exposure process is improved.
[0035]
Next, a first modification of the limit switch unit 41A on the left side of FIG. 1 will be described with reference to FIGS. In FIGS. 6 and 7, parts corresponding to FIGS. 1 to 5 are denoted by the same reference numerals, and detailed description thereof will be omitted.
FIG. 6 is an enlarged plan view of the limit switch unit of the present modified example, and FIG. 7 is an enlarged front view of the limit switch unit with a part thereof cut away. In this limit switch unit, side walls 44a and 44b of the frame 44 in the Y direction are respectively provided. Through holes 44c and 44d are formed, a cylindrical movable element 53 is inserted into these through holes 44c and 44d in parallel with the Y axis, and a stopper 54 is fixed to the surface of the movable element 53 in the side walls 44a and 44b. A compression coil spring 55 is interposed between the movable member 53 and the side wall 44b so as to surround the movable member 53. Therefore, in a state where the scanning stage 9 is separated from the movable element 53, the stopper 54 is pressed against the side wall 44a in the + Y direction by the urging force of the compression coil spring 55, and the end of the movable element 53 in the + Y direction is separated from the side wall 44a. It protrudes in the + Y direction. The urging force of the compression coil spring 55 when the stopper 54 is in contact with the side wall 44a is larger than the frictional force between the scanning stage 9 and the base 10 in FIG. 1, and the average of the linear motors 31A and 31B. The driving force is set to be smaller than the normal driving force.
[0036]
An operation plate 49 is fixed to a side surface of the stopper 54, and a micro switch 50 is fixed at a position on the frame 44 where the operation plate 49 passes. When the micro switch 50 contacts the operation plate 49 and closes, the supply of the drive current to the linear motors 31A and 31B is cut off, and when the operation plate 49 is open apart, the linear motors 31A and 31B are driven. Has become.
[0037]
In this modification, when the scanning stage 9 moves in the direction of the arrow 51 (-Y direction) and starts pushing the mover 53, the mover 53 and the stopper 54 move in the -Y direction. Thereafter, when the operation plate 49 fixed to the stopper 54 closes the microswitch 50, the driving force from the linear motors 31A and 31B to the scanning stage 9 disappears. At this time, since the compression coil spring 55 has a sufficient force to push back the scanning stage 9, the compression coil spring 55 pushes the scanning stage 9 back in the + Y direction via the stopper 54 and the movable element 53, 50 is opened to allow supply of a drive current to the linear motors 31A and 31B. Subsequent operations are the same as those in the examples of FIGS.
[0038]
Next, a second modification of the limit switch unit 41A on the left side of FIG. 1 will be described with reference to FIGS. 8 and 9, parts corresponding to those in FIGS. 1 to 5 are denoted by the same reference numerals, and detailed description thereof will be omitted.
FIG. 8 is an enlarged plan view of the limit switch unit according to the present modification, and FIG. 9 is an enlarged front view of the limit switch unit. A movable pin 58 is rotatably supported about the rotating pin 57 as an axis. Further, a tension coil spring 59 is stretched between the side surface of the mover 58 on the −Y direction side and the convex portion 56d at the upper end of the base 56 in the −Y direction. Is applied. However, the left side surface of the mover 58 contacts the step 56c on the base 56, and the mover 58 is supported so that it cannot rotate further clockwise. The urging force of the tension coil spring 59 in a state where the mover 58 is in contact with the step 56c is larger than the frictional force between the scanning stage 9 and the base 10 in FIG. It is set so as to be smaller than the average driving force.
[0039]
The microswitch 50 is fixed on the base 56 in the rotation direction of the lower right slope 58 b of the mover 58. When the micro switch 50 contacts the slope 58b and closes, the supply of the driving current to the linear motors 31A and 31B in FIG. 1 is cut off, and when the slope 58b is open apart, the linear motors 31A and 31B are driven. It has become.
[0040]
In this modification, when the scanning stage 9 moves in the direction of the arrow 51 (-Y direction) and starts pushing the right side surface 58a of the movable element 58, the movable element 58 is rotated counterclockwise (in the θ direction) about the rotation pin 57 as an axis. ) To rotate. Thereafter, when the inclined surface 58b of the mover 58 closes the micro switch 50, the driving force from the linear motors 31A and 31B to the scanning stage 9 disappears. At this time, since the tension coil spring 59 has a sufficient force to push the scanning stage 9 back, the tension coil spring 59 pushes the scanning stage 9 back in the + Y direction via the mover 58, and the microswitch 50 is opened. Thus, a drive current can be supplied to the linear motors 31A and 31B. Subsequent operations are the same as those in the examples of FIGS.
[0041]
In the above-described embodiment, for example, as shown in FIG. 1, the limit switch unit 41A is fixed on the base 10, but the limit switch unit 41A is attached to the scanning stage 9 side, and the limit switch unit 41A A member that contacts the mover 46 may be attached to the position.
Further, for example, an elastic member such as rubber may be used instead of the tension coil springs 47 and 48 in FIG. Further, for example, the movable element 53 may be formed of an elastic member such as rubber without forming a through hole in the side wall 44b in FIG. 7, and the scanning stage 9 may be pushed back by the elastic member.
[0042]
Further, in the above-described embodiment, the linear motors 31A and 31B are used as the driving device of the scanning stage 9. However, in the case where another electromagnetic driving device such as a voice coil motor (VCM) is used as the driving device. The present invention is also applicable. However, in particular, a driving device such as a linear motor or a VCM that allows the scanning stage 9 to move freely when the driving power is cut off is advantageous.
[0043]
In the above embodiment, the present invention is applied to the reticle stage of the scanning type exposure apparatus. However, the present invention may be applied to the wafer stage. Further, for example, in a batch exposure type exposure apparatus (stepper or the like), when the allowable movement range of the stage is defined by the limit switch, the stage is automatically moved by applying the present invention. It can be returned to the range.
[0044]
As described above, the present invention is not limited to the above-described embodiment, and can take various configurations without departing from the gist of the present invention.
[0045]
【The invention's effect】
According to the present invention, for example, when the moving table runs out of control and activates the switch means, the moving table is automatically returned to the allowable movement range by the push-back means, and the switch means returns to the non-operating state. Therefore, there is an advantage that it is not necessary to push back the moving table manually.
According to the exposure apparatus of the present invention,Even if these stages run away, it is not necessary for the operator to intervene and interrupt the exposure process, thereby improving the throughput (productivity) of the exposure process.
[0046]
When the push-back means has an elastic member, there is no need to separately provide a power source such as a drive motor, and the configuration is simple.
Further, when the driving means is a linear motor, the moving table can be freely moved by cutting off the driving power, so that there is an advantage that the moving table can be easily moved by the push-back means of the present invention.
[Brief description of the drawings]
FIG. 1 is a plan view showing a reticle stage as an embodiment of a stage device according to the present invention.
FIG. 2 is a front view of FIG.
FIG. 3 is an enlarged plan view showing a limit switch unit 41A in FIG.
4A is a front view of FIG. 3, and FIG. 4B is a front view showing a state in which a microswitch 50 is closed.
FIG. 5 is an enlarged view of a main part showing a relationship between a reference plate 42 and an origin sensor 43 in FIG.
FIG. 6 is an enlarged plan view showing a first modification of the limit switch unit 41A of the embodiment.
FIG. 7 is a front view in which a part of FIG. 6 is cut away.
FIG. 8 is an enlarged plan view showing a second modification of the limit switch unit 41A of the embodiment.
FIG. 9 is a front view of FIG. 8;
FIG. 10 is a configuration diagram showing a conventional scanning type exposure apparatus.
FIG. 11 is a perspective view showing an exposure operation of the scanning exposure apparatus.
FIG. 12 is a plan view showing a conventional reticle stage.
FIG. 13 is a front view of FIG.
[Explanation of symbols]
6 reticle
7. Slit illumination area
8 Fine movement stage
9 Scanning stage
10 base
12YA, 12YB laser interferometer
31A, 31B linear motor
34A, 34B Linear guide
41A, 41B Limit switch unit
44 frames
46 mover
47, 48, 59 Extension coil spring
49 Working plate
50 micro switch
53 mover
55 Compression coil spring
58 mover

Claims (6)

A moving table on which the positioning target is placed;
A base on which the moving table is movably mounted in a predetermined direction,
An electromagnetic drive device for driving the moving table in the predetermined direction with respect to the base,
Switch means for interrupting a drive current circuit to the electromagnetic drive device when the moving table has moved beyond the allowable movement range in the predetermined direction with respect to the base;
Pushing-back means for generating an urging force for pushing back the moving table toward the permissible moving range with respect to the base, earlier than the actuation of the switch means;
When the moving table moves beyond the allowable moving range against the urging force, the occurrence of an error is notified and the supply of the driving current is stopped in response to the interruption of the driving current circuit by the switch means. A drive system for restarting the supply of the drive current when the error is recovered . 2. The push-back unit according to claim 1, wherein the urging force is greater than a frictional force when the moving table is moved with respect to the base and smaller than a driving force of the electromagnetic driving device. Stage equipment. The push-back means, the stage apparatus according to claim 1 or claim 2, wherein the an elastic member. The stage device according to any one of claims 1 to 3, wherein the electromagnetic drive device is a linear motor. The stage device according to any one of claims 1 to 4, further comprising a frame that supports the push-back unit and the switch unit. In an exposure apparatus having a movable reticle stage on which a reticle is mounted and a movable wafer stage that holds and moves a wafer,
6. An exposure apparatus, wherein the stage device according to claim 1 is used for at least one of the reticle stage and the wafer stage.

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