JP2000174101A - Stage device and pattern aligner using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stage device producing a small inertia force when a stage is moved and capable of being reduced in weight and size and a pattern aligner using the stage device. SOLUTION: A work is placed on and fixed to a work chucking table 10 and the work chucking table 10 is held by the vacuum chucking of a first work chucking table fixing part 4 and is moved at high moving speeds by a rough moving mechanism constituted by a Y direction movement rail 1 and an X direction movement aril 2. Also, a second work chucking table fixing part 7 is moved up to fix and hold the work chucking table 10 and the work chucking table 10 is released from being fixed by he vacuum chucking of the first work chucking table fixing part 4 and is finely moved by an X Y θ Z direction movement stage 8 mounted under the work chucking table 10. Since the rough movement mechanism and a fine movement mechanism are separately mounted on a stage device, each movement mechanism can be reduced in weight, can reduce the size of the whole stage device.

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 an exposure apparatus for mounting and moving a work used for producing a large-sized substrate such as a printed circuit board or a liquid crystal substrate.

[0002]

2. Description of the Related Art When exposing an image element pattern on a liquid crystal substrate and a wiring pattern on a printed circuit board, the entire substrate has been exposed collectively by a proximity exposure method or the like. FIG. 9 is a view showing an example of a stage device used in the proximity exposure apparatus and the like. In a proximity exposure apparatus, a mask and a work are arranged close to each other, and a mask pattern is collectively exposed to the work. At this time, in order to expose a mask pattern formed on the mask to a predetermined position on the work, an alignment mark (mask mark) formed on the mask matches an alignment mark (work mark) formed on the work. Thus, the mask and the work are aligned.

When this alignment is performed by moving the work side, a table on which the work is placed and sucked (hereinafter referred to as a work suction table) must be movable in the X, Y, and θ directions. is there. Note that the X direction is a direction parallel to the work suction table surface (for example, the horizontal direction in FIG. 9), and the Y direction is a direction parallel to the work suction table surface.
The direction orthogonal to the direction (optical axis direction, for example, the direction perpendicular to the plane of FIG. 9), and the θ direction are rotations about an axis (optical axis) perpendicular to the XY plane.

For this reason, as shown in FIG. 9, a stage device comprises an X stage 11, a Y stage 12, a θ stage 13
, And a work suction table 10 having a vacuum suction groove for holding the work by, for example, vacuum suction or the like is placed thereon. Also,
The Z stage 14 has no relation to the alignment, but is provided for setting a gap between the mask and the work. The X stage 11, the Y stage 12, and the θ stage 13
It is driven by driving means (not shown), and moves in the X and Y directions, respectively, and rotates about the optical axis. As means for driving each of the stages 11, 12, and 13, for example, a driving means as shown in FIG. 1 of Japanese Patent Publication No. 4-9379 is used.

Exposure is performed by the stage device as follows. The work is placed on the work suction table 10 and a vacuum is supplied to the work holding vacuum suction groove to fix and hold the work by vacuum. The mask mark and the work mark are detected by the alignment microscope. The work suction table 10 is moved in the X direction, the Y direction, and the θ direction so as to overlap each other, and the mask and the work are aligned. After the alignment is completed, the entire work is exposed at once.
By the way, recently, the work has become larger. For example, liquid crystal substrates having a large size of 550 × 650 mm to 650 × 830 mm are becoming mainstream. As the size of the work increases, the weight of the work also increases. Therefore, each moving stage for moving the work in the X, Y, and θ directions also increases in size and weight. Recently, the resolution of liquid crystal display elements has been increased,
The miniaturization of printed circuit board wiring has been required, and the formation of finer and higher-resolution patterns than ever before has been required.

To expose a high-resolution pattern, a reduced projection exposure method using a projection lens is generally used. In the reduced projection exposure, a work is divided into predetermined exposure regions, a mask pattern is reduced and projected on the divided exposure regions by a projection lens, and the work is sequentially moved to expose each divided exposure region. This exposure method is called a step-and-repeat method. When the stage apparatus of FIG. 9 is applied to a step-and-repeat type exposure apparatus,
As shown in FIG. 10, while moving the work W placed on the work suction table 10, the first area → the second area →
.., And the respective regions are sequentially exposed.

FIG. 11 shows the configuration of an exposure apparatus of the step-and-repeat type for a large substrate. As shown in the figure, a mask M on which a mask pattern is marked is placed on a mask stage 21, and light emitted from the light irradiation unit 22 is transmitted to the work suction table 10 via the mask M and the projection lens 23. Irradiation is performed on the work W which is fixed and held. Further, on the base 15, a stage device 20 including a work suction table 10, an X stage 11, a Y stage 12, a θ stage 13, and a Z stage 14 is mounted.

That is, the base 15 has the Y stage 12
Is fixed, and X stage 11 and Z stage 1
4, a work suction table 10 on which a θ stage 13 is provided and a work W is placed and held on the θ stage 13
Is attached. The θ stage 13 is used for movement in the θ direction at the time of precise alignment between the mask M and the work. The Z stage 14 is used for movement in the Z direction (optical axis direction) when the image forming position of the projected image of the mask pattern matches the surface of the work. The X stage 11 and the Y stage 12 are used for movement between the divided exposure areas of the work W and movement for precise alignment of the mask M and the work W.

The exposure of the step-and-repeat method by the exposure apparatus shown in FIG. 11 is performed as follows. The work W is placed on the work suction table 10, and the work is fixed and held by vacuum suction. As shown in FIG. 10, the work stage suction table 1 is moved by the X stage 11 and the Y stage 12 so that the first exposure area of the work W comes to the position where the mask pattern is projected.
0 is moved in the X and Y directions. Precise alignment between the mask M and the first exposure area of the work W is performed. A mask mark marked on the mask M;
The work mark WAM marked on the work W is detected by an alignment microscope (not shown), and the X stage 11, the Y stage 12, and the θ stage 1 are overlapped with each other.
3, the work suction table 10 is moved in the X direction, the Y direction,
The mask M and the workpiece W are aligned by moving in the θ direction.

[0010] Exposure light is irradiated from the light irradiation unit 22
The first area of the work W is exposed. Next, the work suction table 1 is moved so that the second exposure area of the work W comes to the position where the mask pattern is projected.
0 in the X and / or Y directions. After the precise alignment between the mask M and the work W, the second area of the work W is exposed. The above movement of the work W → precise positioning of the mask M and the work W → exposure is repeated to expose all divided areas.

[0011]

However, since a large work is heavy, it is necessary to use Y, X, Z,
Each stage of θ must be large and sturdy. Naturally, the weight of the stage itself also increases. X, Y
The stages 11 and 12 are required to have a moving distance that can move over the entire surface of the work and a high-speed movement (for example, 200 mm in 0.5 seconds) to improve the throughput in the movement between the divided exposure regions. On the other hand, in the alignment between the mask and the work, a resolution of 1 μm or less is required so that accurate alignment can be performed. Such a moving mechanism having both functions is large and heavy, such as a mechanism using a linear motor. Therefore, the total weight of the θ · Z · X stages 13, 14, and 11 moved by the Y stage is 200 to 300 kg as shown in FIG.

Here, when moving between the divided exposure regions of the work (for example, from the first region to the second region in FIG. 10), in order to shorten the time as much as possible, the Y stage 12 uses θ.Z.X. The stages 13, 14, and 11 are suddenly started and suddenly stopped at a predetermined position (a position within a range where the mask M and the work W can be aligned, and a position where a work mark can be detected by an alignment microscope). This is a 200-300kg θ ・ Z ・ X stage 13,1
Since the vehicle 4 and 11 suddenly start and stop, a very large inertia force is applied to the entire apparatus. further,
Since the projection lens 23, the mask stage 21, the light irradiating section 22, and the like are also fixed to the base 15 of the exposure apparatus, the entire apparatus vibrates due to the inertial force. High-precision exposure cannot be performed until this vibration has subsided. This leads to a decrease in throughput.

In order to maintain the throughput, it is necessary to provide a means for canceling the inertial force in the exposure apparatus. The only way to cancel this inertial force is to increase the weight of the base 15 on which the stage device 20 is mounted. In the case of this example, in order to cancel the moving inertial force of the stage of 200 to 300 kg, the weight of the base is 5 to 10 t.
(Tons). The total weight of the stage device and the base reaches 5.2t to 10.3t.

As described above, the exposure apparatus for exposing a large substrate by the step-and-repeat method has a problem that the apparatus weight is extremely heavy and the apparatus cannot be miniaturized. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a first object of the present invention is to provide a mechanism capable of precise movement such as alignment between a mask and a work, and a high-speed movement distance corresponding to the width of the work. By separately providing a mechanism capable of moving the work suction table at a high speed, the inertia force at the time of moving the work suction table at a high speed is reduced, and the weight of the stage device is reduced. A second object of the present invention is to reduce the size of an exposure apparatus using the above stage device.

[0015]

In order to solve the above-mentioned problems, in the present invention, a coarse moving mechanism for moving between divided exposure regions at a high speed and a fine moving mechanism for aligning a mask and a work are separately provided. To be provided. Then, when moving the work suction table between the exposure areas, the work suction table is fixed to the coarse moving mechanism, and is moved so that the processing area of the work is substantially at a predetermined processing position. Next, the work suction table is released from the coarse movement mechanism and fixed to the minute movement mechanism, and is minutely moved so that the work area of the work is precisely at a predetermined processing position.

In the present invention, since the coarse moving mechanism and the minute moving mechanism are separately provided as described above, each moving mechanism can be reduced in size and weight, and the entire stage device can be reduced in size and weight. can do. That is, the coarse moving mechanism only needs to have a function of moving only the work suction table at a high speed and stopping at the approximate position, so that it is not necessary to have a strong structure and the weight can be reduced. Further, the minute moving mechanism does not need to be moved over a long distance at high speed, so that the weight can be reduced. Further, since only the work suction table is moved at a high speed by the coarse moving mechanism, the inertia force during the movement is small, and the weight of the base for canceling the inertial force can be reduced. Therefore, the weight of the stage device including the base can be significantly reduced as compared with the conventional device. Accordingly, the size of the exposure apparatus can be reduced.

[0017]

1 and 2 are views showing the configuration of a stage device according to an embodiment of the present invention. FIG. 1 is a perspective view of the stage device according to the present embodiment, and FIG. It is sectional drawing of a stage device. The stage device of the present embodiment includes a mechanism for coarsely moving the work suction table 10 at a high speed,
It comprises a mechanism for minutely moving the work suction table 10 for positioning the mask and the work. As a mechanism for coarsely moving the work suction table 10 in the XY directions, a base 15 on which a Y-direction moving rail 1 (referred to as a Y-rail 1) and an X-directional moving rail 2 (referred to as an X-rail 2) are mounted thereon. It is provided above. The X rail 2 is attached to the Y rail 1 so as to be movable in the direction of the arrow in FIG. 1 (the left and right direction in FIG. 1), and the X rails 2 are connected by connecting rods 3 so that they can be synchronized when moving.

A first work suction table fixing part 4 for holding and fixing the work suction table 10 is mounted on the X rail 2, and the first work suction table fixing part 4 is shown in FIG. Is attached to the X rail 2 so as to be movable in the X direction (the front-back direction in the figure). The X rail 2 and the first work suction table fixing unit 4 are driven by a drive mechanism (not shown), and move on the Y rail 1 and the X rail 2 respectively. As a mechanism for driving the X rail 2 and the first work suction table fixing unit 4, for example,
A device using a ball screw, a device using a timing belt, or the like can be used. In short, a moving mechanism having a function of moving at high speed and stopping at a general position may be used.

FIG. 3 shows an example of a driving mechanism using a ball screw. As shown in the figure, a motor 33 is attached to a ball screw 32 provided with two moving portions 31a, and the ball screw 3
By rotating the X rail 2, the X rail 2 attached to the moving unit 31a moves in the direction of the arrow (Y direction) in the figure. FIG. 4 shows an example of a driving mechanism using a timing belt. Moving portions 31a are provided at two positions on the timing belt 34, the timing belt 34 is moved by the motor 33, and the X rail 2 attached to the moving portion 31a is moved. The drive mechanism of the first work suction table fixing section 4 can be configured similarly to FIGS.

Returning to FIGS. 1 and 2, the first work suction table fixing section 4 is provided for holding and fixing the work suction table 10 during rough movement and moving the work suction table 10 at high speed. In order to fix the work suction table 10 by, for example, vacuum suction, the work suction table fixing section 4 has a vacuum suction hole 5a and a vacuum system 5b.
Is provided. In addition, 2 of the work suction table 10
On one side, a fixed portion 6 to be fixed by the first work suction table fixing portion 4 is provided. In order to move the work suction table 10 at high speed, the first work suction table fixing unit 4 uses the work suction table 1.
When holding / fixing the first workpiece suction table fixing section 4, a vacuum is supplied to the vacuum system 5 b.
For vacuum suction. If the fixed portion 6 is made of, for example, a leaf spring, it has elasticity, so that fixing by vacuum suction is easy.

On the other hand, on a base 15 below the work suction table 10, as shown in FIG. 2, an XYθZ direction moving stage 8 (hereinafter, referred to as an XYθZ stage 8) for minutely moving the work suction table at the time of positioning. Provided. A second work suction table fixing unit 7 is mounted on the θ stage of the XYθZ stage 8, and the work suction table 10 is fixed to the second work suction table fixing unit 7 from the back surface. For example, it has a vacuum suction hole 9a and a vacuum system 9b. When the work suction table 10 is fixed by the second work suction table fixing unit 7 in order to slightly move the work suction table 10, the second work suction table fixing unit 7 is moved by the Z-direction moving stage of the XYθZ stage 8. Then, the electromagnetic valve 9c is opened, and the work suction table 10 is vacuum-sucked by the second work suction table fixing unit 7.

Further, the second work suction table fixing section 7
When the workpiece suction table 10 is released from the fixed state and the workpiece suction table is moved at a high speed by the coarse moving mechanism as described above, the second workpiece suction table fixing section 7 is lowered by the Z-direction moving stage of the XYθZ stage 8. Then, the solenoid valve 9d is opened, and air is blown out from the vacuum suction hole 9a of the second work suction table fixing portion 7. further,
The base 15 where the work suction table 10 moves is also provided with a hole-to-vacuum system 15a for jetting air, and when the work suction table 10 is moved, air is also jetted therefrom. Thereby, the work suction table 10 can be moved smoothly.

FIG. 5 is a diagram showing a configuration of an exposure apparatus using the stage device of the present embodiment. As shown in FIG. 11, a mask M on which a mask pattern is marked is placed on a mask stage 21, and light emitted from the light irradiation unit 22 is attracted to the workpiece through the mask M and the projection lens 23. The work W fixed and held on the table 10 is irradiated. An alignment microscope 24 for positioning the mask M and the work W is provided on the work suction table 10. When aligning the mask M and the work W, the alignment microscope 24 moves from the dotted line position to the solid line position in the figure, and the alignment microscope 24 detects the mask mark and the work mark.
The position of the mask M and the work W is adjusted by moving 0. Other configurations are the same as those shown in FIGS.

Next, the exposure processing by the exposure apparatus of this embodiment will be described. After the exposure of the first exposure area of the work W is completed, the work W is moved so that the next exposure area of the work W falls within the irradiation range.
To move. At the time of movement between the work exposure areas, as shown in FIG. 6, in a state where the work W is mounted and fixed on the work suction table 10, a vacuum is supplied to the first work suction table fixing portion 4, and the work suction table 10 And the first work suction table fixing unit 4 are fixed. In this state, the X-rail 2 and / or the first work suction table fixing unit 4 is driven to move the work suction table 10 to move the work W between the divided exposure areas (see FIG. 10). . At this time, as shown in FIG. 6, air is blown from the second work suction table fixing portion 7 and the base 15 to reduce the moving load of the X rail 2 and the first work suction table fixing portion 4, It is preferable that the work suction table 10 can be moved smoothly.

When the movement of the work W between the exposure areas is completed, the ejection of the air from the second work suction table fixing unit 7 is stopped, and the vacuum is supplied to the vacuum system 9b. Then, as shown in FIG. 7, the Z-direction moving stage of the XY.theta.
Then, the work suction table fixing section 7 is raised, and the work suction table 10 is fixed to the second work suction table fixing section 7. Further, the vacuum suction of the first work suction table fixing section 4 is released. The fixed work suction table 10 is slightly lowered by the Z-direction moving stage. In this state, the mask mark and the work mark are detected by the alignment microscope 24, and the XYθZ stage 8 is driven so that the two are superimposed on each other. Is aligned. XYθZ
In order to reduce the load on the stage 8, it is preferable to blow air from the base 15.

When the alignment between the mask M and the work W is completed, exposure light is emitted from the light irradiating section 22, and the work W is irradiated with the exposure light via the mask M and the projection lens 23, and the exposure area of the work W is exposed. Is exposed. When the exposure of the work W is completed, a vacuum is supplied to the first work suction table fixing section 4 to fix the work suction table 10 to the first work suction table fixing section 4, and the second work suction table fixing section is fixed. Then, the second work suction table fixing unit 7 is lowered together with the XYθZ stage 8 by the Z-direction moving stage of the XYθZ stage 8. Then, air is blown from the second work suction table fixing unit 7 and the base 15. The work suction table 10 is slightly raised by the Z-direction moving stage. Next, returning to the above, the work W is moved so that the next exposure area of the work W falls within the irradiation range.

By configuring the stage device as described above, the weight of the stage device and the base can be reduced as follows. (a) As shown in FIG. 8, the work suction table 10 on which the work W is placed weighs 10 to 20 kg (this is the same as the conventional example). (b) X used to move between the exposure areas of the work W
The rail 2 and the Y rail 1 should be 20kg ~ including the driving mechanism.
30 kg. Here, the coarse moving mechanism is 10 to 20 k.
Since only the function of moving the work suction table 10 of g at a high speed and stopping it at the approximate position is sufficient, there is no need to have a sturdy structure and no high-resolution drive mechanism.
Therefore, the weight can be reduced. (c) The weight of the XYθZ stage 8 for positioning is 20 to 20 even if the weight of the second work suction table fixing unit 7 is adjusted.
30 kg. The XYθZ stage 8 has a mask M
A high-resolution driving mechanism is required to perform precise alignment between the workpiece and the workpiece W, but the moving distance may be about ± 1 mm, which is the stop precision error when moving between the exposure areas. There is no need to move the distance at high speed. Therefore, the weight can be reduced.

(D) Work suction table 1 that moves at high speed
0 is 10 to 20 kg as described above, and accordingly, the inertia force during movement is small. For this reason, the weight of the base 15 for canceling the inertial force can be reduced, and the weight of the base 15 may be about 500 kg. (e) As described above, the weight of the XYθZ stage 8 is 20 to
30 kg, the Y rail 1 and the X rail 2 are 20 kg to 30 kg including the drive mechanism, and the work suction table 10 is
20 kg and the weight of the base 15 is 500 kg, so that the total weight of the stage device and the base 15 is 550
580 kg. This is 1/10 or less of the weight shown in the prior art.

[0029]

As described above, the following effects can be obtained in the present invention. (1) Since a moving mechanism having a moving distance corresponding to the width of the work and moving it at high speed and a moving device groove for performing precise movement such as alignment of the mask and the work are provided independently,
Each moving mechanism can be reduced in size and weight, and the entire stage device can be reduced in size and weight. (2) Since only the work suction table is moved when moving between the exposure areas of the work, the generated inertial force is small. Therefore, the weight of the base for canceling the inertial force can be reduced. Therefore, the size of the exposure apparatus can be reduced by the stage device.

[Brief description of the drawings]

FIG. 1 is a diagram (perspective view) showing a configuration of a stage device according to an embodiment of the present invention.

FIG. 2 is a diagram (cross-sectional view) illustrating a configuration of a stage device of the present embodiment.

FIG. 3 is a diagram illustrating an example of a driving mechanism using a ball screw.

FIG. 4 is a diagram illustrating an example of a drive mechanism using a timing belt.

FIG. 5 is a diagram showing a configuration of an exposure apparatus using the stage device according to the embodiment of the present invention.

FIG. 6 is a view showing a state in which the work W is placed and fixed on the work suction table 10;

FIG. 7 is a view showing a state in which the work suction table 10 is fixed to a second work suction table fixing section 7;

FIG. 8 is a diagram illustrating the weight of the stage device and the base according to the embodiment of the present invention.

FIG. 9 is a diagram showing an example of a stage device used for a proximity exposure apparatus or the like.

FIG. 10 is a diagram illustrating an exposure procedure using a step-and-repeat method.

FIG. 11 is a diagram showing an apparatus configuration of an exposure apparatus of a large-size substrate, which is of a step-and-repeat type.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Y-direction moving rail (Y rail) 2 X-direction moving rail (X rail) 3 Connecting rod 4 First work suction table fixing part 6 Fixed part (leaf spring) 7 Second work suction table fixing part 8 XYθZ direction Moving stage 10 Work suction table 15 Base 21 Mask stage 22 Light irradiation unit 23 Projection lens 24 Alignment microscope M Mask W Work

Claims (3)

[Claims] 1. A work suction table, a coarse movement mechanism for moving the work suction table by the width of a work placed on the work suction table, and a positioning error caused by movement of the work suction table by the coarse movement mechanism. A stage device comprising: a fine moving mechanism for moving a work suction table by an amount to be corrected; and switching the coarse moving mechanism and the fine moving mechanism to move the work suction table. 2. A work suction table on which a work is mounted, and a coarse movement for moving the work suction table in two orthogonal directions parallel to the surface of the work suction table by the width of the work mounted on the work suction table. The mechanism and the work suction table are finely moved in the two orthogonal directions by an amount to correct an alignment error caused by the movement of the work suction table by the coarse moving mechanism, and the work suction table is perpendicular to the work suction table surface. The work suction table is fixed to the coarse movement mechanism, and the work area is moved so that the work area is approximately at the predetermined processing position. And then fixed to the micro-movement mechanism, and micro-moved so that the processing area of the workpiece is precisely at the predetermined processing position. Door stage apparatus according to claim. 3. A work suction table, a coarse moving mechanism for moving the work suction table by a width of a work placed on the work suction table, and a positioning error caused by the movement of the work suction table by the coarse movement mechanism. A minute movement mechanism for moving the work suction table by an amount to be corrected; a stage device for moving the work suction table by switching between the coarse movement mechanism and the fine movement mechanism; An exposure apparatus that exposes a work placed on a suction table to a mask pattern for each pre-divided area. When the work is moved from the divided area to the area, the work is attracted by the coarse moving mechanism. When moving the table and aligning the mask and the work, the micro-movement mechanism described above Exposure apparatus characterized by moving the click suction table.