JPH08162385A - Stage device and driving method thereof - Google Patents

Abstract

PURPOSE: To enhance a stage device in device or wafer processing throughput by a method wherein a Y stage is changed in acceleration depending on the direction in which it is accelerated. CONSTITUTION: The output section 13 of a stage device outputs a power to accelerate a Y stage 5 in a first direction, and an output section 14 outputs a power to accelerate the Y stage in a second direction. A main control system 9 selects either the output section 13 or the output section 14 by a switch 15 in accordance with the direction in which the Y stage 5 is driven to drive a Y axis drive section 10 to accelerate and move the Y stage 5. Next, the power outputted from the output section 13 or the output section 14 is so set as to accelerate the Y stage 5 to such an extent that an X stage 4 is restrained from jumping up from the surface of a V guide 11. As the V guide 11 is located out of the center of gravity of the X stage 4, the upper limit of the acceleration of the Y stage 5 in the first direction is smaller than that in the second direction, and the acceleration of the Y stage 5 is capable of being set relatively higher in the second direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage device having a V-flat guide surface and stacking X and Y stages which move in two directions orthogonal to each other in a horizontal plane. This apparatus is particularly useful for a semiconductor exposure apparatus.

[0002]

2. Description of the Related Art A semiconductor exposure apparatus and various inspection apparatuses have a stage device on which a photosensitive substrate (wafer), devices, etc. are mounted and which is freely movable in a horizontal plane. This allows
For example, a pattern of a mask or a reticle is sequentially exposed on a plurality of shot areas on a wafer by a step-and-repeat method or a step-and-scan method.

FIG. 5 shows the structure and control system of the stage device. The pattern on the mask 1 is exposed on the resist layer on the wafer 3 via the projection optical system 2. The wafer 3 is placed on the X stage 4. The X stage 4 is mounted on the Y stage 5 via the V guide 11 and the flat guide 12. The Y stage 5 is placed on the base 6 via the V guide 11 and the flat guide 12. Y
The stage 5 can be moved along the V guide 11 in the Y-axis direction (left-right direction on the paper surface of FIG. 5) by the Y-axis drive unit 10. Further, the X stage 4 can be moved along the V guide 11 in the X axis direction (direction perpendicular to the paper surface of FIG. 5) by the X axis drive unit (not shown).

A movable mirror 7 is installed on the X stage 4 to detect the position of the X stage in the Y-axis direction.
The position of the moving mirror 7 in the Y-axis direction is detected by irradiating the moving mirror 7 with the laser beam of the interferometer 8 and detecting the reflected light by the interferometer 8. Similarly, a movable mirror (not shown) is also provided at the position in the X-axis direction, and the position is detected by an interferometer (not shown). The position information of the interferometer is input to the main control system 9.
When the coordinate position of the target position is input, the main control system 9 calculates the deviation from the current position of the X stage 4, and the main control system 9 determines the deviation between the Y position and the X axis driving unit 10 according to the deviation. Is controlled to move the X stage 4 to the target position. Main control system 9
Controls the speed of the X stage 4 by monitoring the position of the X stage 4 from the interferometer at any time during the movement to the target position.

[0005]

When accelerating to move the Y stage 5 (deceleration is considered to be acceleration in the opposite direction in this specification), if the acceleration of a certain value or more is applied, the Y stage 5
The X stage 4 placed on the top jumps up as shown in FIGS. When the Y stage 5 is accelerated (decelerated) to the left (first direction) in the paper surface, the X stage 4 jumps up along the right surface (left surface) of the groove of the Y stage 5. When the Y stage 5 is accelerated (decelerated) in the right direction (second direction) in the paper surface, the X stage 4 jumps up along the left surface (right surface) of the groove of the Y stage 5. Therefore, even if the Y stage is stopped near the target position, the X stage vibrates and accurate positioning cannot be performed. In the end, you have to wait until the vibration has subsided before measuring. This leads to the drawback of increasing the time required to position the X stage at the target position in the Y axis direction. For this reason, the Y stage 5 is moved at the upper limit of acceleration so that the X stage 4 does not jump up.

This limits the throughput in processing wafers, devices, etc., and therefore poses a problem when processing a large amount. The present invention aims to improve such throughput.

[0007]

Conventionally, the acceleration when accelerating the Y stage has been the same when moving in either of the Y-axis directions (first direction and second direction). However, in general, the position of the V guide is X when viewed in the Y-axis direction.
It is out of the center of gravity of the stage. In this case, according to the research by the present inventor, it was found that the acceleration at which the X stage jumps up differs depending on the moving direction. That is, when the direction with the V guide is the first direction and the direction without the V guide is the second direction when viewing the Y-axis direction from the center of gravity of the X stage,
It was found that when the Y stage was moved in the first direction, the X stage was easy to jump up, and when it was moved in the second direction, the X stage was difficult to jump up. Conventionally, the upper limit of the acceleration is determined by looking at the person who easily jumps up (first direction). That is, in the case of the second direction, jumping does not occur even if the acceleration is increased. Conversely, there was room for improvement in throughput here. Therefore, the present inventor has conceived that the acceleration is changed between the first direction and the second direction, and the acceleration is relatively increased in the second direction, and the present invention has been completed.

That is, the first aspect of the present invention is to provide a "Y stage,
It is composed of an X stage mounted on it via a V guide and a flat guide, and a Y axis drive unit for moving the Y stage in the Y axis direction. When the position of the V guide is viewed in the Y axis direction, In a method of driving a stage device at a position deviated from the center of gravity of the stage, when the direction with the V guide is the first direction and the direction without the V guide is the second direction when the Y-axis direction is viewed from the center of gravity, the Y stage is moved to the second direction. A method of increasing the acceleration when accelerating in the direction 2 is larger than the acceleration when accelerating in the first direction (claim 1). ".

In this case, the upper limits of the first and second accelerations are such that the X stage does not jump up (claim 2).
Is preferred. The second is a stage device (claim 3) used in the driving method of the present invention (claim 1). This apparatus (claim 3) includes a Y stage, an X stage mounted on the Y stage via a V guide and a flat guide,
A Y-axis drive unit (Y-axis drive unit 10) for moving the Y-stage in the Y-axis direction is provided, and the position of the V guide is located outside the center of gravity of the X-stage when viewed in the Y-axis direction. This device (Claim 3) is further provided with V when viewed in the Y-axis direction from the center of gravity.
When the direction with the guide is the first direction and the direction without the guide is the second direction, the acceleration that accelerates to the first direction is output.
Output part (first output part 13) and accelerate in the second direction,
A second output section (second output section 14) that outputs a larger acceleration than the first output section (first output section 13), and a first output section (first output section 13) when accelerating in a first direction. Is selected, and when accelerating in the second direction, the second output section (second output section 14)
And a control unit that accelerates the Y stage via the Y-axis drive unit (Y-axis drive unit 10) by the accelerations output from the first and second output units selected by the selection unit. Prepare

In this case, the first and second output sections (output section 1
It is preferable that (3, 14) output the upper limit of acceleration at which the X stage does not jump up (claim 4).

[0011]

As described above, the acceleration at which the X stage jumps up differs depending on the first direction and the second direction in the Y axis direction. The acceleration that causes jumping up when accelerating in the first direction and the acceleration that causes jumping up when moving in the second direction are measured in advance. By doing so, it is possible to set the acceleration that does not cause jumping in each direction. If there is no jump,
Since the larger the acceleration, the higher the throughput, it is preferable to set the upper limit of the acceleration that does not jump up (claims 2 and 4). The acceleration set for each direction is
It is stored in the second output section (claims 3 and 4). When the stage is accelerated and moved in each of the first and second directions, the output unit is selected by the selection unit, and the stage is accelerated by the stored acceleration to move the stage.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of a stage device according to an embodiment of the present invention. The stage device of the present embodiment is incorporated in an exposure device that exposes the pattern of the mask 1 onto the wafer 3 via the projection optical system 2. The Y stage 5 is placed on the base 6, and the V stage (not shown) and the flat guide (not shown) formed on the base 6 contact the Y stage. The Y stage 5 moves along this guide. The X stage 4 is placed on the Y stage 5, and both are in contact with each other via the V guide 11 and the flat guide 12. The X stage 4 guides the Y stage 5 on the guides 11, 1
Can move along 2.

A movable mirror 7 is installed on the X stage 4.
The light beam emitted from the interferometer 8 to the moving mirror 7 is moved to the moving mirror 7.
Is reflected. When the interferometer 8 detects the reflected light beam, the position of the X stage 4 in the Y axis direction is output to the main control system 9. The main control system 9 drives the Y-axis drive unit 10 based on the output from the interferometer 8 and the movement target position.
Although not shown, the driving configuration of the X stage 4 is similar to that of the Y stage.

The stage device has a first output section 13 and a second output section 14. The first output unit 13 outputs the acceleration toward the left (first direction) in the plane of the Y stage 5, and the second output unit 14 outputs the acceleration toward the right (second direction) in the plane of the Y stage 5. To do. The main control system 9 is Y
The switch 15 (an example of a selection unit) selects the first output unit 13 or the second output unit 14 based on the direction in which the stage 5 is driven (accelerated). The main control system 9 drives the Y-axis drive unit 10 according to the acceleration from the selected output unit. This accelerates and moves the Y stage.

Next, the acceleration output from the output units 13 and 14 will be described. Here, the acceleration is set to an upper limit acceleration at which the X stage 4 does not jump over the surface of the V guide 11 when the Y stage 5 is driven. The jumping acceleration is different when the Y stage 5 is accelerated in the first direction and when it is accelerated in the second direction. This is because the V guide 11 is located at a position deviated from the center of gravity of the X stage 4, so that the action of the rotational moment upon acceleration is different.

One method of determining the acceleration is to obtain it by experiment. When the Y stage is moved from the movement start position to the target position, the acceleration is changed and the movement is repeated many times. At this time, the acceleration is gradually increased, and the upper limit is set to a value immediately before the time required to position the X stage 4 exceeds a predetermined allowable value.

As another method, a method of calculating from the balance of the force when the X stage 4 starts to jump up and the balance of the rotational moment around the center of gravity of the X stage 4 is calculated based on the shape of the X stage 4. There is. Specifically, the force balance is the balance between the force generated along the surface of the V guide and the frictional force generated on the V guide due to the acceleration of the Y stage. The balance of the rotational moment around the center of gravity is the balance of the force in the direction of rotation about the center of gravity of the X stage generated on the surface of the V guide due to the acceleration of the Y stage.

The upper limits of the respective accelerations thus obtained are stored in the output units 13 and 14. In the case of this stage apparatus, the upper limit of acceleration when the Y stage 5 is accelerated in the first direction is smaller than that when it is accelerated in the second direction. FIG. 2 shows the relationship between time and speed when moving in the first direction from the predetermined position to the target position with the acceleration thus set. In this case, the direction of acceleration is different between acceleration and deceleration. The acceleration is changed depending on the direction, and the time required to reach a constant speed is shorter when decelerating.

3 and 4 show the relationship between time and speed when starting to move in the second direction (FIG. 3) and the relationship between time and speed when starting to move in the first direction (FIG. 4). ) Is shown. In this case, the time until the X stage 4 reaches a constant speed is shorter when the movement starts in the second direction than in the first direction.
On the stage prototyped for the present invention, as a result of the experiment,
The upper limit acceleration at which the X stage 4 did not jump up in the first direction was about 6 m / sec, and the upper limit acceleration at which the X stage 4 did not jump up in the second direction was about 10 m / sec.

Further, the meanings of the X stage and the Y stage are arbitrary, and even if they are reversed, they are within the scope of the present invention.

[0021]

According to the present invention, since the acceleration is changed depending on the direction of accelerating the Y stage, the time required to set the moving speed of the Y stage to the destination (including zero) in the direction of large acceleration is conventionally. Can be shorter. Therefore, the total time required to move the X stage to a plurality of target positions in sequence is significantly reduced. This improves the throughput of processing devices and wafers.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a structure and a control system of a stage device according to an embodiment of the present invention.

FIG. 2 is a graph showing the relationship between time and speed when the Y stage is moved in the embodiment.

FIG. 3 is a graph showing the relationship between time and speed when moving the Y stage in the first direction in the example.

FIG. 4 is a graph showing the relationship between time and speed when moving the Y stage in the second direction in the example.

FIG. 5 is a schematic diagram showing a structure and a control system of a conventional stage device.

FIG. 6 is an explanatory diagram showing jumping up of the X stage when the Y stage is accelerated in the first direction.

FIG. 7 is an explanatory diagram showing jumping up of the X stage when the Y stage is accelerated in the second direction.

[Explanation of symbols]

 4 X stage 5 Y stage 7 Moving mirror 8 Interferometer 9 Main control system 11 V guide 12 Flat guide 13 First output section 14 Second output section 15 Switch (an example of selection section)

Claims (4)

[Claims] 1. A Y stage, an X stage mounted on the Y stage via a V guide and a flat guide, and a Y axis drive unit for moving the Y stage in the Y axis direction. In a driving method of a stage device, which is located at a position deviated from the center of gravity of the X stage when viewed in the Y-axis direction, a direction in which the V guide is seen from the center of gravity in the Y-axis direction is a first direction, When the direction is the second direction, when accelerating the Y stage in the first direction, the acceleration thereof is made larger than the acceleration when accelerating in the second direction. Driving method. 2. The method of driving a stage apparatus according to claim 1, wherein the acceleration is set to an upper limit of acceleration at which the X stage does not jump up. 3. A Y stage, an X stage mounted on the Y stage via a V guide and a flat guide, a Y axis drive unit for moving the Y stage in the Y axis direction,
In the stage device in which the position of the V guide is deviated from the center of gravity of the X stage when the position of the V guide is viewed in the Y axis direction, the direction in which the V guide is located is the first direction when the Y direction is viewed from the center of gravity. When the second direction is the direction of the
A first output unit that outputs an acceleration that accelerates in the first direction, a second output unit that accelerates in the second direction, and a second output unit that outputs an acceleration greater than the first output unit, and an acceleration time in the first direction. A first output unit is selected and a second output unit is selected when accelerating in the second direction; and an acceleration output from the first or second output unit selected by the selection unit. And a control unit for accelerating the Y stage via the Y-axis drive means. 4. The stage apparatus according to claim 3, wherein said first and second output means output an upper limit of acceleration at which said X stage does not jump up.