JPH07237061A - Stage device - Google Patents

Abstract

PURPOSE:To adjust the viscous resistance acting on a movable stage to an appropriate value. CONSTITUTION:A protruding piece disposed at the lower face of a movable stage 2 is vertically moved by a viscous resistance adjusting means 11. Viscous resistance caused to the movable stage 2 is adjusted by the contact quantity of the protruding piece 11B and a viscous fluid 12 increased/decreased by the vertical movement of the protruding piece 11B so as to be able to adjust the damping quantity to the appropriate value. As a result, the movable stage 2 can be positioned into a specified position without conducting a hunting action.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage apparatus, and is suitable for application to a movable stage apparatus used in, for example, a semiconductor manufacturing apparatus or a liquid crystal display panel manufacturing apparatus.

[0002]

2. Description of the Related Art Conventionally, in this type of manufacturing apparatus, a movable stage device having a positioning mechanism having a structure shown in FIG. 5 has been used. This movable stage device horizontally drives a movable stage 2 guided on a holding table 1 by using a feed mechanism 3. The position of the movable stage 2 is measured by a laser interferometer 4, and based on the measurement result. The feed position of the movable stage 2 is fed back controlled by the controller 5. Each part of this movable stage device is configured as follows.

A guide surface (V-shaped groove 1A and horizontal surface 1B) is formed on the holding table 1, and the movable stage 2 is guided on these guide surfaces via needle bearings 6A and 6B. As a result, the movable stage 2 is movable along the guide surface in the direction of arrow A in the figure or in the opposite direction. Further, the feed mechanism 3 used for driving the movable stage 2 is mainly composed of a motor 3A and a feed screw 3B connected to this output shaft via a coupling (not shown). When the movable stage 2 is driven, the output shaft of the motor 3A fixed to the holding table 1 via the support member 3C is rotated to rotate the feed screw 3B, and the nut 3D fixed to the movable stage 2 is rotated. The movable stage 2 is driven. Further, a reflecting mirror 2A is fixed to one end of the movable stage 2, and the position is detected by detecting the return light of the laser light emitted from the laser interferometer 4 toward the reflecting mirror 2A. There is. The movable stage device is configured by a combination of these parts.

[0004]

By the way, in the movable stage device of this structure, the generation of the damping amount necessary for precise positioning (1 [μm] or less) is generated by the feed screw 3B and nut 3D as shown in FIG. It depends on the oil film 3E filled between and. Therefore, in order to precisely position the movable stage 2, it is necessary to periodically supply oil to maintain a predetermined film thickness and maintain a state where a constant damping amount can be obtained. In particular, under the present circumstances where the movable stage 2 becomes larger and higher positioning accuracy is required, the lubrication interval tends to become shorter and shorter. Further, this configuration may cause a shortage of damping amount in the future.

The present invention has been made in consideration of the above points, and it is possible to obtain a sufficient damping amount corresponding to an increase in the size and accuracy of the movable stage, and also to easily control the amount of the damping amount. It is intended to propose a stage device that can do this.

[0006]

In order to solve such a problem, an explanation will be given by associating it with FIG. 1 showing an embodiment, and in a stage apparatus according to claim 1, a holding table (1) and a holding table ( 1) A stage device comprising a movable stage (2) guided movably in a horizontal direction on a top surface of the holding table (1) in a horizontal direction and filled with a viscous fluid (12). Groove (13) and viscous fluid (12)
So that it can come into contact with the projecting piece (11B) disposed on the lower surface of the movable stage (2), and the projecting piece (11B) is moved up and down to bring the projecting piece (11B) into contact with the viscous fluid (12). A viscous resistance varying means (11) for adjusting the amount and causing a viscous resistance according to the contact amount on the movable stage (2) is provided. In the stage device according to the second aspect, the movable stage (2) moves in the horizontal direction by driving the drive shaft, and the groove (13) is provided at a position facing the drive shaft. In the stage apparatus according to claim 3, viscous resistance variable means (1
1) is a projecting piece (11B) when decelerating the movable stage (2)
The amount of contact between the viscous fluid (12) and the viscous fluid (12) is increased to increase the viscous resistance.
1B) and the viscous fluid (12) are reduced in contact amount to further reduce the viscous resistance (29).
In the stage apparatus according to claim 4, the viscous fluid (12) is an electrorheological fluid. In the stage apparatus according to the fifth aspect, the tip of the projecting piece (11B) is formed in a wedge shape in cross section, and the cross section of the groove (13) is formed in a female shape with respect to the wedge shape.

[0007]

In the stage apparatus according to claim 1, the viscous resistance varying means (11) moves the protrusion (11B) up and down to adjust the contact amount between the protrusion (11B) and the viscous fluid (12). As a result, the magnitude of the viscous resistance acting on the movable stage (2) is adjusted, so that the damping amount required when positioning the movable stage (2) can be adjusted. In the stage apparatus according to claim 2, the groove (13) has a drive shaft (3).
Since it is provided at a position facing B), the movable stage (2) can be accurately moved in the horizontal direction. In the stage device according to claim 3, the control means (29) causes the protrusion piece (11B) and the viscous fluid (1) during deceleration of the movable stage (2).
2) The amount of contact with the viscous resistance is increased by increasing the amount of contact with the viscous fluid, and the amount of contact between the protruding piece (11B) and the viscous fluid (12) is decreased during the deceleration of the movable stage (2) to reduce the viscous resistance. Therefore, the movable stage (2) can be moved at high speed and positioned with high accuracy. In the stage apparatus according to the fourth aspect, since the electrorheological fluid is used as the viscous fluid (12), the viscosity of the electrorheological fluid can be changed according to the voltage applied to the protrusion (11B) and the groove (13). . Therefore, the adjustment range of the damping amount can be widened. In the stage apparatus according to claim 5, the projecting piece (11
Since the tip of (B) has a wedge-shaped cross section and the groove (13) is formed in a female shape with respect to this wedge-shaped cross section, the protrusion (1
A desired damping amount can be obtained by adjusting the gap between 1B) and the groove (13).

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

In FIG. 1 in which parts corresponding to those in FIG. 5 are designated by the same reference numerals, 10 indicates the movable stage device according to the present embodiment as a whole, and a damping amount adjusting mechanism 11 is provided on the lower surface of the movable stage 2. A groove 13 filled with a viscous fluid 12 is formed on the surface of the holding table 1. Incidentally, the viscous fluid 12 is made of oil or the like, which is not easily deteriorated or evaporated even if left in the atmosphere for a long time, and is made of a material which can obtain an appropriate viscosity. In this way, the damping amount adjusting mechanism 11 attached to the lower surface of the movable stage 2 is attached to the portion facing the feed screw 3B and not interfering with the feed screw 3B (or on the nut 3D).
The generation of the damping amount can be switched by vertically moving the protruding piece 11B extending downward from 1A (in the direction of arrow B). The control device 29 controls the damping amount adjusting mechanism 11 by a signal from the controller 5.

That is, the controller 29 controls the protrusion 11B so that the protrusion 11B is lowered into the viscous fluid 12 filled in the groove 13 and brought into contact with the viscous fluid 12 when the deceleration is required to generate damping. At this time, the amount of descent is adjusted to adjust the protrusion 11
If the contact amount between B and the viscous fluid 12 is changed, the viscous resistance is also increased or decreased, and the damping amount can be adjusted accordingly. On the other hand, during the period when the amount of damping is unnecessary,
That is, the control device 29 controls the protrusion 11B so as not to come into contact with the viscous fluid 12 during a period other than when the movable stage 2 is decelerated. As a result, the movable stage 2 can be driven without a load.

Next, the detailed structure of the damping amount adjusting mechanism 11 will be described with reference to FIG. Damping amount adjustment mechanism 11
Is mainly composed of two mechanical parts, that is, a projection driving mechanism and a descent amount adjusting mechanism. Here, the projecting piece drive mechanism is a drive portion that switches between whether or not the viscous fluid 12 and the projecting piece 11B are brought into contact with each other, and the descent amount adjusting mechanism is the lowest point position of the descending projecting piece 11B, that is, It is a drive unit for adjusting the amount of drop and controlling the magnitude of viscous resistance.

Here, the descent amount adjusting mechanism will be described first, and the protrusion driving mechanism will be described later. The descending amount adjusting mechanism is attached to a base member 14 having an L-shaped cross section, which is fixed to the lower surface of the movable stage 2. A linear guide 14A extending in parallel with the moving direction A of the movable stage 2 is fixed to the top plate portion of the base member 14, and a linear guide 1 extending in the up-down direction (direction of arrow B) is attached to the side plate portion.
4B is fixed.

A cam 16 is provided on each of the linear guides 14A and 14B via sliders 15A and 15B having a U-shaped cross section.
A and 16B are attached, respectively, and the two cams 16A and 16B are locked so that they can be interlocked with each other. That is, the cam 16A and the cam 16B are
A shaft is fixed to a guide groove 16A1 formed so as to pass through A by a bearing portion of a shaft bearing 17 whose shaft is fixed to a cam 16B being slidably mounted.

By the way, this guide groove 16A1 is shown in FIG.
As shown in FIG. 4, the work is processed so as to gradually rise in the direction of arrow A. Therefore, as the cam 16A moves in the direction of arrow A or in the opposite direction, the bearing fitted in the guide groove 16A1 moves upward or downward along the inner wall of the guide groove 16A1. It is designed to be adjusted. For example, when the cam 16A is driven in the direction of arrow A, the center position of the shaft bearing 17 fitted in the groove 16A1 is relatively lowered, and the cam 16B is pushed down.
On the other hand, when the cam 16A is driven in the direction opposite to the arrow A, the bearing 17 with shaft fitted in the groove 16A1 is inserted.
The center position of the cam 16B is relatively raised, and the cam 16B is pushed up.

The cam 16A can be driven by the rotation of a motor 19 fixed to the base member 14 via a mounting member 18. That is, the feed screw 20 that transmits the rotation amount of the motor 19 to the cam 16A is coupled to the output shaft of the motor 19 at one end via a coupling (not shown), while the other end is fixed to the base member 14. It is rotatably supported by the member 21. The nut 22 attached to the feed screw 20 is translated in parallel with the cam 16A in accordance with the rotation of the feed screw 20 to move the horizontal position of the cam 16A, and thus the tip position of the lowered protruding piece 11B. The position of the cam 16B to be determined can be determined.

Next, the protruding piece drive mechanism will be described. This protruding piece drive mechanism is attached to the cam 16B described above. The cam 16B is also provided with two linear guides 23A and 23B similar to the base member 14 described above. Here, the linear guide 23A is fixed to the bottom plate portion of the cam 16B so as to extend in the direction of arrow A, and the linear guide 23B is fixed to the side plate portion so as to extend in the direction of arrow B. A cam 25 and a protruding piece 11B are attached to each of the linear guides 23A and 23B via sliders 24A and 24B having a U-shaped cross section. Here, the cam 25 and the slider 24B are locked so as to interlock with each other, and the projecting piece 11B moves up and down in conjunction with the cam 25.

That is, the cam 25 is provided with a two-step through groove having different heights and a guide groove 25A which is a steeply inclined groove portion connecting these through grooves, and the shaft has a slider 24 in the guide groove 25A.
The bearing portion of the shaft bearing 26 fixed to B is rotatably attached. In response to the vertical movement of the shaft bearing 26, the protrusion 11B fixed to the slider 24B moves vertically through a through hole formed in the bottom of the cam 16B. However, in the case of this protruding piece drive mechanism, the stationary position of the bearing that moves along the inner wall of the guide groove 25A is configured to be either the upper position or the lower position. This is because the projecting piece drive mechanism is a mechanism for the purpose of moving the projecting piece 11B at high speed. Therefore, in this mechanism, the air cylinder 27 is used to drive the cam 25. The air cylinder 27 is fixed to the bottom plate portion of the cam 16B via a fixing member 28. The cam 25 is driven by inserting / removing the piston 27A whose tip portion is fixed to the cam 25, and the protruding piece 11B.
With or without contact with the viscous fluid 12.

In the above structure, the movable stage device 1
The positioning operation by 0 will be described. Here, the positioning operation will be described by dividing it into a period from the stationary state until the movable stage 2 that has been accelerated and reached a constant speed is decelerated, and a period from the start of deceleration to the positioning to the target position. Incidentally, the tip height of the protrusion 11B, that is, the protrusion attached to the viscous fluid 12 so that an appropriate damping amount is generated between the protrusion 11B and the viscous fluid 12 before the movable stage 2 is conveyed. It is assumed that the attachment amount of the piece 11B is adjusted by the descent amount adjusting mechanism.

First, the period from the start of driving the movable stage 2 to the deceleration will be described. At the start of acceleration, the air cylinder 27 drives the cam 25 in the direction opposite to the arrow A in response to a command from the control device 29 to move the shaft bearing 26 fitted in the guide groove 25A from the lower position to the upper position of the guide groove 25A. The protruding piece 11B that was in contact with the viscous fluid 12 is quickly pulled out from the viscous fluid 12.
In this state, the movable stage 2 is accelerated by the feed mechanism 3, and after reaching a constant speed, it is conveyed to the vicinity of the target point at a constant speed. At this time, the viscous resistance does not act on the projecting piece 11B (that is, there is no load), so that the movable stage 2 can be easily driven even if a relatively small motor is used as the motor 3A.

When the target point approaches soon and shifts to the deceleration operation, the air cylinder 27 drives the cam 25 in the direction of arrow A according to a command from the control device 29, and the shaft bearing 26
Is moved from the upper position to the lower position of the guide groove 25A. As a result, the protrusion 11B is quickly lowered into the viscous fluid 12 and viscous resistance is generated. This viscous resistance generates an appropriate damping amount required for delicate positioning. As a result, as shown in the speed-time characteristic curve diagram shown in FIG. 3A, the movable stage 2 can be quickly stopped at a predetermined position after deceleration.

On the other hand, in the case of the conventional movable stage apparatus, it is difficult to properly adjust the damping force, and when the damping force is lowered, the speed shown in FIG.
As shown in the time characteristic curve diagram, there is a problem that the movable stage 2 does not converge its positioning even after deceleration and becomes a so-called hunting state. However, in the case of the movable stage device 10 described in the present embodiment, even at this time, the motor 19 of the descending amount adjusting mechanism is rotated to move the cam 16A in the direction of the arrow A, and the projecting piece. If the height of the lowest point of 11B is adjusted to be slightly lower, it is possible to generate a viscous resistance of an appropriate size, and it is possible to get out of the hunting state.

With the above-described structure, it is possible to realize the movable stage device 10 which can obtain a damping amount of an arbitrary size when the movable stage 2 is positioned, and the movable stage 2 can be swiftly moved without the risk of hunting. The position can be positioned. In the present embodiment, the protrusion 11B is brought into contact with the viscous fluid 12 only during deceleration, but the protrusion 11B may be slightly brought into contact with the viscous fluid 12 during acceleration or constant speed. As a result, the protrusion 11B can be decelerated more quickly during deceleration.
Since the viscous fluid 12 comes into contact with the viscous fluid 12, the stage device can be quickly positioned.

In the above embodiment, the protruding piece 11B is used.
Although the case where a flat plate is used has been described above, the present invention is not limited to this, and another shape may be used as long as it can generate a viscous resistance of an appropriate size with the viscous fluid 12. For example, as shown in FIG. 4 in which parts corresponding to those in FIG. 2 are denoted by the same reference numerals, a projecting piece 30 having a wedge-shaped cross section may be used instead of the projecting piece 11B. Further, in this case, the cross-sectional shape of the groove 13A filled with the viscous fluid 12 may be formed in a female shape with respect to the cross-sectional shape of the projecting piece 30. In this way, a desired damping amount may be obtained by viscous resistance obtained by adjusting the size of the gap d formed between the protrusion 30 and the groove 13A. Further, in this case, the locking can be applied by completely contacting the projecting piece 30 and the inner wall of the groove 13A.

Further, in the above-mentioned embodiment, the case where the movable stage device 10 is used as the positioning stage of the semiconductor manufacturing apparatus or the liquid crystal display panel manufacturing apparatus has been described, but the present invention is not limited to this, and is guided on the holding table 1. The present invention can be widely applied to a movable stage device configured to horizontally guide the movable stage 2 thus formed.

Further, in the above-mentioned embodiment, the case where the viscous fluid 12 having a proper viscosity such as oil is used and the contact amount with the projecting piece 11B is adjusted (including the case where it does not contact) has been described. The present invention is not limited to this, and an electrorheological fluid whose viscosity can be controlled by electricity may be used instead of the viscous fluid 12. The electrorheological fluid can change the viscosity of the electrorheological fluid by adjusting the voltage applied to the groove 13 and the protrusion 11B.
It is possible to change the viscous resistance in a wider range than changing the viscous resistance only by the amount of contact between the viscous fluid 12 and the viscous fluid 12. As a result, the stage device can be positioned with higher accuracy.
In addition, since the viscosity of the electrorheological fluid can be changed by the applied voltage as described above, the stage device can be positioned at high speed.

[0026]

As described above, in the stage device according to the first aspect, the viscous resistance varying means adjusts the magnitude of the viscous resistance acting on the movable stage,
Since the damping amount necessary for positioning the movable stage is obtained, it is possible to obtain the damping amount corresponding to the size increase and the precision improvement of the movable stage. In the stage device according to the second aspect, since the groove is provided at a position facing the drive shaft, the movable stage can be accurately moved in the horizontal direction.
In the stage apparatus according to the third aspect, the movable stage can be moved at high speed and positioned with high accuracy by the control of the control means. In the stage device according to the fourth aspect, since the electrorheological fluid is used as the viscous fluid, a desired damping amount can be obtained at high speed. In addition, the adjustment range of the damping amount can be widened by combining it with the vertical movement of the protrusion. In the stage apparatus according to claim 5, since the tip of the projecting piece has a wedge-shaped cross section and the groove is formed in a female shape with respect to this wedge-shaped cross section, the gap between the projecting piece and the groove is adjusted. As a result, a desired damping amount can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an overall configuration of a stage device according to the present invention.

2A and 2B are a side view and a front view for explaining a damping amount adjusting mechanism.

FIG. 3 is a characteristic curve diagram for explaining a positioning operation of a movable stage.

FIG. 4 is a side view and a front view for explaining another embodiment of the damping amount adjusting mechanism.

FIG. 5 is a schematic perspective view showing an overall configuration of a conventionally used stage device.

FIG. 6 is a schematic cross-sectional view showing a cross-sectional structure of a feed screw.

[Explanation of symbols]

1 ... holding table, 2 ... movable stage, 3 ... feed mechanism,
3A, 19 ... Motor, 3B, 20 ... Feed screw, 3C
...... Support member, 3D, 22 ...... Nut, 4 ...... Laser interferometer, 5 ...... Controller, 6A, 6B ...... Needle bearing, 10 ...... Movable stage device, 11 ...... Damping amount adjusting mechanism, 11A ...... Body part, 11B, 30 ...
… Protrusions, 12 …… Viscous fluid, 13, 13A …… Groove, 14
... Base member, 14A, 14B, 23A, 23B ...
Linear guide, 16A, 16B, 25 ... Cam, 16A
1, 25A ... Guide groove, 17, 26 ... Shaft bearing, 18, 21 ... Mounting member, 24A, 24B ... Slider, 27 ... Air cylinder, 27A ... Piston,
28: fixing member, 29: control device.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location H01L 21/027 // B23Q 15/24 7352-4M H01L 21/30 503 A 7352-4M 515 G

Claims (5)

[Claims] 1. A stage device comprising a holding base and a movable stage guided on the holding base so as to be movable in the horizontal direction, wherein a viscous fluid is provided on an upper surface of the holding base along the horizontal direction. And a protrusion provided on the lower surface of the movable stage so as to be able to come into contact with the viscous fluid, and an amount of contact between the protrusion and the viscous fluid that is moved up and down. And a viscous resistance varying means for causing the movable stage to generate viscous resistance according to the contact amount. 2. The stage according to claim 1, wherein the movable stage is driven in the horizontal direction by driving a drive shaft, and the groove is provided at a position facing the drive shaft. apparatus. 3. The viscous resistance varying means increases the amount of contact between the projecting piece and the viscous fluid to increase the viscous resistance during deceleration of the movable stage, and the viscous piece during the deceleration of the movable stage. The stage device according to claim 1 or 2, further comprising a control unit configured to reduce a contact amount between the viscous fluid and the viscous fluid to reduce a viscous resistance. 4. The stage apparatus according to claim 1, wherein the viscous fluid is an electrorheological fluid. 5. The projection according to claim 1, wherein the tip of the projection is formed in a wedge shape in cross section, and the cross section of the groove is formed in a female shape with respect to the wedge shape. The stage device according to claim 2, claim 3, or claim 4.