JPH09190224A - XY stage controller - Google Patents

Abstract

(57) Abstract: An XY stage control device enables an XY stage to be easily operated at high speed in an operation section where trajectories are orthogonal and adjacent to each other. SOLUTION: Position command means 4 for generating position command values for the X axis and Y axis of an XY stage 10 based on sequentially applied target positions for the X axis and Y axis, and XY so as to follow this position command value. Stage X and Y stage 8,
In the XY stage control device that includes the servo devices 6 and 7 for driving and controlling 9, the operation section of one stage and the operation section of the other stage drive the XY stage adjacent to each other. The position command value is output to the servo device at the start of deceleration in the operation section or during the deceleration period to start acceleration in the operation section of the other stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a controller for an XY stage used in a scan type semiconductor exposure apparatus or the like, and more particularly to an apparatus for interpolating adjacent orthogonal loci to enable continuous operation.

[0002]

2. Description of the Related Art Conventionally, in controlling an XY stage, an X
When moving from the directional operation to the Y direction or from the Y direction to the X direction, the XY stage is temporarily stopped. Therefore, it is necessary to perform deceleration, stop, and acceleration each time the moving direction is changed, so high-speed operation cannot be performed. This is a very big problem as one of the factors that hinder the improvement of productivity, especially in the use of semiconductor manufacturing equipment.

On the other hand, in Japanese Unexamined Patent Publication (Kokai) No. 62-84304, high speed is achieved by synthesizing target speed patterns for decelerating and accelerating adjacent operation sections for arbitrary adjacent trajectories of the industrial robot. It proposes to realize smooth operation. Also, JP-A-63-102
Japanese Patent Publication No. 07 proposes to obtain a smooth target position by determining a certain correction ratio and obtaining a new teaching point by linear interpolation with respect to a passing point that does not require strict positioning.

[0004]

However, the structure of Japanese Patent Laid-Open No. 62-84304 corresponds to an arbitrary locus such that the object of use is an industrial robot and the operation axes of adjacent operation sections are the same. In order to do this, it is necessary to combine the target speed patterns during deceleration and acceleration, and
Since it is necessary to integrate the target velocity pattern to obtain the target position, there is a problem that the algorithm becomes complicated as a whole.

Further, in the configuration of Japanese Patent Laid-Open No. 63-10207, there is a problem in that the calculation for obtaining a new teaching point is required and the algorithm becomes complicated.

In view of this problem of the prior art, it is an object of the present invention to make it easier for the XY stage control device to operate the XY stage at high speed in the operation sections where the trajectories are orthogonal and adjacent to each other. .

[0007]

In order to achieve the above object, according to the present invention, a position for generating an X-axis and Y-axis position command value of an XY stage based on sequentially given target positions of the X-axis and the Y-axis. An XY stage drive that includes an instruction unit and a servo device that drives and controls the X and Y stages of the XY stage so as to follow the position instruction value, and the operation section of one stage and the operation section of the other stage are adjacent to each other. In the XY stage control device for performing the above, the position command means outputs the position command value to the servo device at the start of deceleration in the operation section of one stage or during the deceleration period to start acceleration in the operation section of the other stage. It is characterized by being a thing.

[0008]

According to this, when deceleration starts in the operation section of one stage, acceleration of the other adjacent operation section is started. Therefore, the stage can be moved at high speed.

[0009]

【Example】

[Embodiment 1] FIG. 1 is a block diagram showing a configuration of an XY stage control device according to an embodiment of the present invention. In the figure, 1 is a storage means for storing a target acceleration, a target speed, a target position, etc., 2 is an X-axis position target value generating means for generating an X-axis position target value, and 3 is a Y-axis position target value. Y-axis position target value generation means 4, 4 is a position target value generation means including an X-axis position target value generation means 2 and a Y-axis position target value generation means 3, and 5 is an X-axis position target value generation means 2 and a Y-axis position. A locus interpolation unit that outputs the position target values generated by the target value generation unit 3 to the X-axis servo device 6 and the Y-axis servo device 7 as position command values, and 6 is the X-axis position input from the locus interpolation unit 5. An X-axis servo device that drives the X stage 8 so that the X stage 8 follows the command value, 7
Is Y to the position command value of the Y-axis input from the locus interpolation means 5.
A Y-axis servo device that drives the Y stage 9 so that the stage 9 follows, 8 is an X stage that is a drive target, 9 is a Y stage that is a drive target, and 10 is an XY composed of an X stage 8 and a Y stage 9. It's a stage.

The operation of the XY stage control device configured as described above will be described.

The X-axis position target value generating means 2 comprises a storage means 1.
The target X-axis position value x _r is calculated from the target acceleration, the target speed, the target position of the X-axis, and the X-axis movement start position, which are stored in the equation (1), according to the equation (1).

[0012]

[Equation 1] The Y-axis position target value generation means 3 is also the X-axis position target value generation means 2
Similarly to the above, the Y-axis position target value is calculated according to the equation (2).

[0013]

[Equation 2] FIG. 2 shows the position target value of the trapezoidal velocity pattern generated by the position target value generating means 4, and shows the velocity component and the acceleration component of the position target value pattern at the same time.

The X-axis servo device 6 controls so that the X stage 8 follows the X-axis position command value input from the trajectory interpolation means 5, and the Y-axis servo device 7 is input from the trajectory interpolation means 5. Since the Y stage 9 is controlled so as to follow the Y axis position command value, the XY stage 10 can be moved to a desired position on the XY plane as a whole.

The locus interpolating means 5 takes out the target position data one by one from the target position data string stored in the storage means 1 and supplies it to the position target value generating means 4 as a parameter. When it is determined that the XY stage 10 has reached the target position, the entire target wafer on the XY stage 10 is scanned by repeating the procedure of fetching the next target position data from the storage unit 1.

FIG. 4 is a flow chart showing the operation algorithm of the trajectory interpolation means 5 in the apparatus of FIG. The locus interpolation means 5 first determines in step S1 from the target position data stored in the storage means 1 whether or not only the X axis is operating in the current operation section. When it is determined that only the X axis is operating, it is determined in step S2 whether only the Y axis is operating in the next operation section. When it is determined that only the Y-axis operates, it is determined in step S3 whether or not the X-axis deceleration has started in the current operation section. When the deceleration is started, in step S4, the Y-axis position target value generating means 3 is activated for the next operation section to start the Y-axis acceleration. If it is determined in step S3 that deceleration has not started, the X-axis position target value generation means 2
The target position generated by is input to the X servo device 6 and the X axis drive is continued.

On the other hand, when it is determined in step S1 that only the X-axis is not operating, the process proceeds to step S5, and it is determined whether only the Y-axis is operating in the current operation section. When it is determined that only the Y axis is operating, it is determined in step S6 whether only the X axis is operating in the next operation section. When it is determined that only the X axis operates, it is determined in step S7 whether or not the Y axis deceleration is started in the current operation section. If the deceleration is started, in step S8, the X-axis position target value generating means 2 is activated for the next operation section to start the X-axis acceleration. If it is determined in step S7 that deceleration has not started, the target position generated by the Y-axis position target value generating means 3 is set to Y.
Input to the axis servo device 7 to continue driving the Y axis.

When both axes are operating in the current operation section, it is determined that the XY stage 10 has reached the target position, and the axes are continuously driven until the current operation section ends.

The position target value generating means 4 and the trajectory interpolating means 5 described above are realized as an algorithm of a CPU (not shown).

For example, FIG. 3 shows how the X-axis speed and the Y-axis speed change when the current operation axis operates only on the X axis and the next operation axis operates only on the Y axis. Further, when the movement of a certain point of the XY stage 10 is observed on the XY plane, it becomes as shown in FIG. In the figure, P _k is a target position, Q _k is a deceleration start position, and R _k is an acceleration end position (k is n or n +).
1). The XY stage 10 does not stop at P _k ,
Curve a smooth passage inside the apex.

With this apparatus, the time required to scan the entire surface of the wafer can be shortened, and the throughput can be improved.

In the position target value generating means 4 of this embodiment, the acceleration of the other axis is started immediately after the deceleration of the other axis is started. However, as shown in FIG. 6, the acceleration of the other axis is started. A configuration in which is delayed by a predetermined time is also conceivable. Further, in the present embodiment, the target value generally called a trapezoidal velocity pattern as shown in FIG. 2 is generated, but by generating the target value of the pattern as shown in FIG. It is possible to make it difficult to excite the vibration of the stage 10.

[0023]

As described above, according to the present invention,
It is possible to move the stage at high speed because it is possible to move in a curve inside the apex angle without stopping at a target position where it is not necessary to pass over it.

The stage can be moved at high speed by adding a simple algorithm without giving the target positions of the points forming the curve in detail.

Further, since the position target value may be directly given to the servo device, the trouble of integrating the speed target value is unnecessary, and it is not necessary to consider the numerical error at the time of integration.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an XY stage control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a target value pattern generated by an X-axis position target value generation means and a Y-axis position target value generation means in the apparatus of FIG.

FIG. 3 is a diagram showing how the X-axis speed and the Y-axis speed change in the apparatus of FIG.

4 is a flowchart illustrating the operation of the trajectory interpolation means in the device of FIG.

5 is a diagram showing the movement of an XY stage on the XY plane in the apparatus of FIG.

FIG. 6 is a diagram showing another state of changes in the X-axis speed and the Y-axis speed in the apparatus of FIG.

7 is a diagram showing another target value pattern generated by the X-axis position target value generating means and the Y-axis position target value generating means in the apparatus of FIG.

[Explanation of symbols]

1: storage means, 2: X-axis position target value generation means, 3: Y-axis position target value generation means, 4: position target value generation means, 5: locus interpolation means, 6: X-axis servo device, 7: Y-axis Servo device, 8: X stage, 9: Y stage, 10: XY stage.

Claims (1)

[Claims] 1. A position command means for generating position command values for the X-axis and Y-axis of an XY stage on the basis of sequentially applied target positions for the X-axis and Y-axis, and the XY so as to follow this position command value. In the XY stage control device, which comprises a servo device for driving and controlling the X and Y stages of the stage, and which drives the XY stage in which the operation section of one stage and the operation section of the other stage are adjacent, An XY stage control which outputs the position command value to the servo device at the start of deceleration in the operation section of one stage or during the deceleration period to start acceleration in the operation section of the other stage. apparatus.