JP3072212B2 - Positioning stage apparatus and exposure apparatus using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning stage device used for a semiconductor exposure apparatus, a precision machine tool, a precision measuring instrument, and the like, and an exposure apparatus using the same.

[0002]

2. Description of the Related Art In semiconductor exposure apparatuses, precision machine tools, precision measuring instruments, and the like, it is required to position a substrate such as a wafer to be exposed, a workpiece or a workpiece with high precision. For this purpose, a static pressure bearing device is used to keep the space between the holding plate that holds the substrate and the workpiece, etc., and the guide surface that guides it non-contact, and by using a linear motor as a drive device that moves the holding plate. A positioning stage device with improved positioning accuracy and speed has been developed. FIG. 8 shows a conventional example of such a positioning stage device.

The positioning stage device E ₀ shown in FIG. 8 is a vertical positioning stage device used for an X-ray exposure device that uses X-rays such as synchrotron radiation as exposure light. An x stage 102 guided by a guide 102a and capable of reciprocating in one direction in a horizontal plane (hereinafter, referred to as an “x direction”);
Is guided by a y guide 103a which is integral with the y axis, and is reciprocally movable in a vertical direction (hereinafter, referred to as "y direction").
A stage 103; a wafer chuck 104 provided on the y stage 103; an x electric cylinder 105 for moving the x stage 102 in the x direction;
An x linear motor 106 that moves by a small amount in the direction;
a y electric cylinder 107 for moving the y stage 103 in the y direction, a y linear motor 108 for moving the y stage 103 by a small amount in the y direction, and a constant tension spring 109 for offsetting the weight of the y stage 103 by tension;
The rod 105a of the x electric cylinder 105 is connected to the x stage 102 via the x gap joint 105b, and the rod 107a of the y electric cylinder 107 is connected to the y gap joint 107.
It is connected to the y stage 103 via b.

The x-gap joint 105b comprises a butting plate 105c integrally provided at the free end of the rod 105a of the x electric cylinder 105, and a pair of L-shaped members 105d projecting from the side of the x stage 102. Patch 105
c is engaged with a gap formed between the side surface of the x-stage 102 and the engaging portion 105e of each of the L-shaped members 105d opposed thereto, and the size of the gap is several microns to several tens.
Micron. When the rod 105a of the x electric cylinder 105 moves forward in response to a command signal on a command line (not shown), the abutment plate 105c abuts on the x stage 102 to move it forward, and the rod 1 of the x electric cylinder 105 moves forward.
When 05a retreats, the butting plate 105c engages with the locking portion 105e of each L-shaped member 105d, and the x-stage 102
Retreat. As a result, the x stage 102 is moved to a position where a few microns remain until the command position in the x direction based on the command signal. The same applies to the y-gap joint 107b.

The x linear motor 106 is connected to the base 1
01 and an x-stage 102
The y linear motor 108 also includes a stator 108a integrated with the x stage 102 and a small movable member 108b integrated with the y stage 103. Each stator 106a, 108a
As shown in FIG. 9, a plurality of coils C ₀ are held in a long coil holder H ₀ , and each movable element is changed by a change in a magnetic field when a current is supplied to each coil C _0. 1
When the x stage 102 and the y stage 103 move by the driving of the x electric cylinder 105 and the y electric cylinder 107 as described above, and when the respective movers 106 b and 108 b move together with these, And a current switching device for detecting a new position of each of the movers 106b and 108b and supplying a current to a predetermined coil.

The wafer chuck 104 has a vertical suction surface 10.
Has a 4a, suction surface 104a adsorbs the wafer W ₀ by vacuum suction force. The position of the wafer chuck 104 in the x direction is monitored by an x interferometer that receives reflected light from an x mirror (not shown) provided on the y stage 103, and the output is negatively fed back to an x servo calculator (not shown), The arithmetic unit drives the x linear motor 106 based on the difference between the command signal transmitted from the command line and the output of the x interferometer, and moves the x stage 102 by a very small amount. Also,
The position of the wafer chuck 104 in the y direction is the y stage 1
The output is monitored by a y interferometer (not shown) that receives the reflected light of the y mirror provided at 03, and the output thereof is negatively fed back to a y servo calculator (not shown). The stage 103 is moved by a very small amount. As described above, the fine movement adjustment by the x linear motor 106 and the y linear motor 108 is performed by the x electric cylinder 105, This is performed after being moved by the y electric cylinder 107, whereby the y stage 103 is finally positioned.

As shown in FIG. 10, the x electric cylinder 105 and the y electric cylinder 107 each include a motor M with a water jacket, a gear train G, and a bearing B.
And a nut N rotatably supported by the nut and a nut N moved in the axial direction.
It is provided integrally with each of the rods 105a, 107a of the x electric cylinder 105 and the y electric cylinder 107.
And the nut N is advanced and retracted by the rotation of the screw rod R. Since the motor M has a water jacket as described above, the heat generated causes x
There is no possibility that the temperature of the stage 102 or the y stage 103 will increase. Further, since the x linear motor 106 and the y linear motor 108 are used only for the positioning servo and do not accelerate or decelerate the stage, the amount of heat generated is extremely small, so that a small-sized design as described above is possible. The positioning stage device E ₀ prevents the deterioration of the positioning accuracy due to the heat generated by the driving devices of the x stage 102 and the y stage 103 as much as possible, and realizes highly accurate and highly responsive positioning by the linear motor. .

[0008]

However, according to the above-mentioned prior art, as described above, the stator of each linear motor has many coils, and the movable element of each linear motor is driven by driving each electric cylinder. When moving to a new position, it is necessary to detect the position of each mover, select a predetermined coil, and supply a current to this coil. Therefore, a complicated current switching device for selecting a coil and supplying a current must be provided, and it is unavoidable that the entire positioning stage device becomes large and complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the related art, and has as its object to provide a positioning stage device which does not require a plurality of coils of a linear motor for fine movement adjustment. Things.

[0010]

In order to achieve the above object, a positioning stage device according to the present invention is provided on a guide surface.
And moving base in a square direction is reciprocally movable, a first driving means for moving the moving table to the side <br/> direction, is moved by a minute amount the mobile base to the side <br/> direction A second driving unit including a linear motor, wherein one of a mover and a stator of the linear motor is provided integrally with the moving table, and the other is driven by the first driving unit. When the moving table moves, it is configured to move with the moving table.

[0011]

According to the above-described apparatus, the moving table is moved to the vicinity of the target position by the first driving means, and then the fine movement is adjusted by the second driving means. When the moving table is moved by the first driving means, the mover and the stator of the linear motor also move with the movement, so that it is not necessary to use a plurality of coils for the linear motor. As a result, a position sensor and a current switching device for selecting a coil are not required.

[0012]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view showing a positioning stage apparatus according to a first embodiment. The exposure apparatus of the present embodiment has an X-ray having an exposure unit that uses X-rays such as synchrotron radiation as exposure light. An exposure apparatus. The vertical positioning stage device E-1 shown in FIG. 1 is guided by an x guide 2a, which is a guide unit integrated with the base 1, and in one direction in a horizontal plane as a guide surface (hereinafter, referred to as “ It is guided by an x stage 2 that is a movable table that can reciprocate in the x direction and a y guide 3a that is a guide unit integrated with the x stage 2 and is vertically moved (hereinafter, referred to as a “y direction”). reciprocate Allowed to)
And y stage 3 is a moving table which is the ability, and the wafer chuck 4 provided y stage 3, a motor <br/> constituting the first driving means in the x direction to move the x stage 2 in the x-direction A certain x electric cylinder 5, an x linear motor 6 which is a second driving means in the x direction for moving the x stage 2 by a very small amount in the x direction, and a pair of y direction motors for moving the y stage 3 in the y direction. Motor y constituting the first driving means
An electric cylinder 7, a pair of y linear motors 8 as second driving means in the y direction for moving the y stage 3 by a very small amount in the y direction, and a constant tension spring 9 for offsetting the weight of the y stage 3 by tension. And the drive unit of the x electric cylinder 5
The rod 5a, which is a member, is connected to the x stage 2 via an x gap joint 5b, and is a driving member of each y electric cylinder 7.
That the rod 7a is y stage 3 through y gap joint 7b
It is connected to.

The x-gap joint 5b includes a butting plate 5c which is a contact means integrally provided at a free end of the rod 5a of the x electric cylinder 5, and a pair of L-shaped members protruding from the side surface of the x stage 2. 5d, and the abutment plate 5c has a side surface of the x-stage 2 and a locking portion 5 of each L-shaped member 5d opposed thereto.
The gap formed between them is loosened, and the size of the gap is several microns to several tens of microns. When the rod 5a of the x electric cylinder 5 moves forward in response to a command signal on a command line (not shown), the abutment plate 5c
When the rod 5a of the x electric cylinder 5 retreats, the abutment plate 5c engages with the locking portion 5e of the L-shaped member 5d to retreat the x stage 2. Thus, the x electric cylinder 5 moves the x stage 2 to a position where a few microns remain until the x direction command position based on the command signal.

The same applies to each y-gap joint 7b.
It is composed of an abutment plate 7c as a contact means and a pair of L-shaped members 7d.

The x linear motor 6 comprises a stator 6a integral with the butting plate 5c of the x gap joint 5b, and an x stage 2
Each of the y linear motors 8 also includes a stator 8a integrated with the butting plate 7c of the y-gap joint 7b, and a small movable element 8b integrated with the y stage 3. Consists of

The stator 6a of the x linear motor 6 is shown in FIG.
As shown in the enlarged view, one coil C ₁ is integrally connected to the butting plate 5c of the x gap joint 5b, and the x stage 2 is driven by the x electric cylinder 5 as described above. When it moves, it moves with it. Each y
Similarly, the stator 8a of the linear motor 8 also includes one coil y
The y stage 3 is integrally connected to the abutment plate 7c of the gap joint 7b, and moves together with the y stage 3 when the y stage 3 is moved by driving each y electric cylinder 7. That is, unlike the conventional stator in which a large number of coils are arranged in series, each of the stators 6a and 8a of the present embodiment is composed of one coil, and the x electric cylinder 5 and the y electric cylinder 7 are driven. At this time, since the coil moves together with the movers 6b and 8b to a position where a few microns are left at the command positions of the x stage 2 and the y stage 3, the positions of the movers 6b and 8b are changed. No need for a position sensor for detecting the current and a current switching device for selectively exciting the coil. Therefore, the size of each of the stators 6a and 8a together with each of the movers 6b and 8b can be greatly reduced. This greatly contributes to simplification.

The wafer chuck 4 has a vertical suction surface.
It has a suction surface for adsorbing the wafer W by vacuum suction force. The position of the wafer chuck 4 in the x direction is the y stage 3
X that receives light reflected by an x mirror (not shown) provided at
The output is monitored by an interferometer, and its output is negatively fed back to an x servo calculator (not shown). The x servo calculator drives the x linear motor 6 based on the difference between the command signal transmitted from the command line and the output of the x interferometer. Then, the x stage 2 is moved. The position of the wafer chuck 4 in the y direction is monitored by a y interferometer (not shown) that receives reflected light from a y mirror provided on the y stage 3, and its output is negatively fed back to a y servo calculator (not shown). y servo calculator is
The y stage 3 is moved by driving the linear motor 8.

Each of the x electric cylinder 5 and each y electric cylinder 7 includes a motor with a water jacket (not shown), a gear train, a screw rod rotatably supported by a bearing, The nuts are moved in the axial direction by the nuts, and the nuts are rods 5a, 7 of the x electric cylinder 5 and the y electric cylinders 7, respectively.
a, the rotation of the motor is transmitted to the threaded rod via a gear train, and the rotation of the threaded rod advances and retreats the nut. There is no possibility that the temperature of the stage 3 will rise. Further, the x linear motor 6 and each y linear motor 8 are used only for the positioning servo, and do not accelerate or decelerate the stage. Therefore, the amount of heat generation is extremely small, and the compact design can be achieved as described above. The positioning stage device E-1
In this way, it is possible to prevent a decrease in the positioning accuracy due to the heat generated by the x-stage and y-stage driving devices as much as possible, to realize highly accurate and highly responsive positioning by the linear motor, and to reduce the size and position of the stator of each linear motor. The omission of the sensor and the current switching device greatly facilitates downsizing and simplification of the entire positioning stage device.

FIG. 3 shows a second embodiment. The positioning stage device E-2 of this embodiment is different from the pair of y electric cylinders 7 of the first embodiment in that a larger y electric cylinder 17 is used. And a rod 17a is connected to the y-stage 3 by a y-gap joint 17b, and a voice coil motor 18 which is a linear motor is provided instead of the x linear motor 6 for fine movement adjustment, and the voice coil motor 18 is fixed. Stator 18b and stator 8 of y linear motor 8
x for b respectively move the x-direction and y-direction
This uses an x auxiliary cylinder 19 and a y auxiliary cylinder 20, which are third driving means in the direction and the y direction .
The x auxiliary cylinder 19 is driven by the same amount in the same direction in synchronization with the x electric cylinder 5, and the y auxiliary cylinder 20 is driven by the same amount in the same direction in synchronization with the y electric cylinder 17. The base 1, x stage 2, y stage 3, wafer chuck 4, x electric cylinder 5, its rod 5a, x clearance joint 5b, y linear motor 8, and constant tension spring 9 are the first.
Since it is the same as the embodiment, it is represented by the same reference numeral, and the description is omitted. In this modification, since it is not necessary to limit the mounting positions of the movers of the y linear motor 8 and the voice coil motor 18, an optimal vibration taking effect and the like when the y linear motor 8 and the voice coil motor 18 are driven are considered. The mounting position can be selected.

FIG. 4 shows a modification of the second embodiment, which is a modification of the rod 5 of the x electric cylinder 5 of the second embodiment.
x gap joints 5b and y connecting a to x stage 2
Instead of y gap joint 17b connecting rod 17a of electric cylinder 17 to y stage 3, x spring joint 25b and y spring joint 2 each consisting of a pair of parallel springs are used.
7b. That is, the x spring joint 25b
Is comprised of a pair of parallel springs 28a and 28b which hold the free end of the rod 5a of the x electric cylinder 5, which are held by the x stage 2 and
“a” is configured to be able to reciprocate finely in the x direction with respect to the x stage 2 within the range of the elasticity of the parallel springs 28a and 28b. Similarly, the y-spring joint 27b includes a pair of parallel springs 29a and 29b, and the rod 17a of the y-electric cylinder 17 is moved within the range where these elasticities allow.
The stage 3 is configured to be finely reciprocated in the y direction with respect to the stage 3.

FIG. 5 shows a positioning stage apparatus according to a third embodiment. The exposure apparatus of the present embodiment is a reduction projection type exposure apparatus having an exposure means for horizontally holding and exposing a substrate such as a wafer (not shown). (Stepper). Positioning stage device E-3 of Figure 5 includes a base 31 having a guide 31b are a pair of guide means extending in a predetermined Direction along which a horizontal guide surface 31a (hereinafter,. As "X direction"), An X stage 32, which is a movable table that is supported on a guide surface 31a in a non-contact manner by a static pressure bearing (not shown) and that can reciprocate along a guide 31b;
Y that is orthogonal to the X direction along the guide surface that is the guide means 2
Stage 33 which is a movable table that can reciprocate in the direction
The substrate such as a wafer is attracted to a suction surface provided on the upper surface of the Y stage 33. The X stage 32 is moved in the X direction by a pair of first electric driving means, that is, an X electric cylinder 34, which is driven alternately or in opposite directions.
That is, the rod 34a, which is a contact means of each X electric cylinder 34, is in contact with each end surface of the X stage 32 in the X direction.
Is driven in the X-direction by the driving force of the other, and is retracted by the driving force of the other X electric cylinder 34. Further, the driving device for moving the Y stage 33 in the Y direction by the X stage 32 has a pair of abutting rods 35c which are in contact with each end surface of the Y stage 33 in the Y direction. The butting rod 35c is moved in the Y direction by the rotation of the screw rod 35a, and the two screw rods 35a are driven in the opposite directions to each other.
Rotated by That is, the Y stage 33 advances in the Y direction by the driving force of one Y motor 35 and moves backward by the driving force of the other Y motor 35.

The X stage 32 and the Y stage 33 respectively hold movable elements 36b and 38b of an X linear motor 36 and a Y linear motor 38 as a second driving means provided for a pair of fine movement adjustments. X linear motor 3
The sixth stator 36a is composed of one coil, and is moved by the same amount in the same direction as the X stage 32 by the X auxiliary motor 39 which is a third driving means driven in synchronization with each X electric cylinder 34. The stator 38a of each of the Y linear motors 38 is also formed of one coil, and is driven in synchronization with each of the Y motors 35 by a Y auxiliary motor 40 serving as third driving means. It is configured to move by the same amount in the same direction as the movement of 33.

FIG. 6 shows an enlarged view of only the stator 36a of one X linear motor 36. The stator 36a is integrated with a nut member 39b screwed to a screw rod 39a rotated by the X auxiliary motor 39. Yes, nut member 39b
Slides along a guide rod 39c provided in parallel with the screw rod 39a. Similarly, the stator 38a of each Y linear motor 38 is screwed to the screw rod 40a rotated by the Y auxiliary motor 40, and is integrated with the nut member 40b that moves along the guide rod 40c.

As in the first embodiment, the X linear motor 36 and the Y linear motor 38 are connected to the X stage 32 and the Y stage 33 by the X electric cylinder 3 based on a predetermined command signal.
By driving the 4 and Y motors 35, they are moved to a position where a few microns are left to their respective commanded positions, and then driven to perform final fine adjustment. The stators 36a and 38a of the X linear motor 36 and the Y linear motor 38 move by the same amount in the same direction in synchronization with the X stage 32 and the Y stage 33, respectively, so that a plurality of coils need to be provided as in the conventional example. Absent.

FIG. 7 shows a modification of this embodiment.
This is because the stator 38a of each Y linear motor 38 is provided integrally with the butting rod 35c driven by one Y motor 35, and the stator 3a of each X linear motor 36
6a is provided integrally with the rod 34a of each X electric cylinder 34. In this modification, each of the stators 36a and 38a
Does not require an auxiliary motor for driving the X stage 32, but the mounting position of each of the stators 36a and 38a with respect to the X stage 32 and the Y stage 33 is limited to a very narrow range. There are restrictions such as the necessity of disposing the cylinders 34 on both sides of the X stage 32.

[0027]

Since the present invention is configured as described above, the following effects can be obtained.

The movable element of the linear motor for fine adjustment
Since the armature moves with the moving table, a linear motor can be used.
There is no need to select the coil by detecting the position of the moving element, and therefore there is no need to provide a position sensor or current switching device for selecting the coil of the linear motor. As a result, downsizing and simplification of the positioning stage device can be promoted.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a positioning stage device according to a first embodiment.

FIG. 2 is an enlarged partial perspective view showing a stator of an x-linear motor of the apparatus shown in FIG. 1 and a connection portion thereof.

FIG. 3 is a perspective view showing a positioning stage device according to a second embodiment.

FIG. 4 is a perspective view showing a modification of the positioning stage device according to the second embodiment.

FIG. 5 is a perspective view showing a positioning stage device according to a third embodiment.

6 is an enlarged partial perspective view showing a stator of an X linear motor of the apparatus of FIG. 5 and a connection portion thereof.

FIG. 7 is a perspective view showing a modification of the positioning stage device according to the third embodiment.

FIG. 8 is a perspective view showing a conventional example.

FIG. 9 is an enlarged partial perspective view showing a part of a conventional stator in an enlarged manner.

FIG. 10 is an explanatory diagram illustrating an electric cylinder.

[Explanation of symbols]

 1, 31 base 2 x stage 3 y stage 4 wafer chuck 5 x electric cylinder 5b x gap joint 6 x linear motor 6a, 8a, 36a stator 6b, 8b, 36b mover 7, 17 y electric cylinder 7b, 17b y gap Coupling 8 y linear motor 18 voice coil motor 19 x auxiliary cylinder 20 y auxiliary cylinder 32 X stage 33 Y stage 34 X electric cylinder 35 Y motor 36 X linear motor 38 Y linear motor 39 X auxiliary motor 40 Y auxiliary motor

Continuation of the front page (51) Int.Cl. ⁷ identification code FI H01L 21/30 503A (58) Investigation field (Int.Cl. ⁷ , DB name) H01L 21/027 B23Q 5/28 G03F 9/00 G12B 5 / 00 H01L 21/68

Claims (11)

(57) [Claims] A moving base which can reciprocate a predetermined Direction on the 1. A guide surface, a first driving means for moving the moving table to the Direction, by a small amount of the mobile base to the Direction A second drive unit including a linear motor to be moved, wherein one of a movable element and a stator of the linear motor is provided integrally with the movable table, and the other is the first drive means. Wherein the movable stage moves together with the movable stage. 2. A movable member is provided integrally with a movable table, and a first driving means is provided on the movable table so as to alternately contact a pair of mutually opposite contact surfaces. Having contact means,
The positioning stage device according to claim 1, wherein a stator is integrally provided with the contacting means. 3. The positioning stage device according to claim 1, wherein the mover is provided integrally with the movable table, and the stator is configured to move by the third driving means. 4. A carriage that can reciprocate in a predetermined direction.
And the motor and the motor
First driving means having a member for moving the moving table;
And second driving means provided with a near motor.
One of the magnet and coil of the motor is
The other is provided at the end of the member
When the moving table moves, the first driving means causes the moving table to move.
To move with the moving table,
The moving table is moved relative to the member by the near motor.
Position that can be moved by a small amount in a fixed direction
Placement stage equipment. 5. The linear motor magnet is integrated with the moving table.
Wherein the coil is moved by the first driving means.
5. The apparatus according to claim 1, wherein the apparatus moves together with the apparatus.
The positioning stage device according to claim 1. 6. The moving table is in an x direction and orthogonal to the x direction.
2. The apparatus according to claim 1, wherein the movable part is movable in the y direction.
6. The positioning stage device according to any one of claims 5 to 5. 7. A linear motor for moving a minute amount in the x direction.
And a linear motor that moves a small amount in the y-direction.
7. The positioning step according to claim 6, wherein
Device. 8. A mirror is provided on the movable base, and the mirror is provided.
The position of the moving table is measured by an interferometer that receives the reflected light from the mirror.
Position and monitor the linear mode based on the output of the interferometer.
8. A motor according to claim 1, wherein said motor is driven.
The positioning stage device according to claim 1. 9. An x-axis capable of reciprocating in the x-direction on a guide surface.
Stage and the x direction for driving the x stage in the x direction
First driving means and the x stage are finely moved in the x direction.
X-direction motor with x linear motor to move by small amount
2, the x-direction with respect to the x-stage.
A y stage that can reciprocate in the orthogonal y direction;
Driving the stage in the y direction with respect to the x stage
The first driving means in the y direction, and the y stage
Y to move by a small amount in the y direction with respect to the stage
A second driving means in the y direction provided with a linear motor.
For example, one previous of the mover and the stator of the x linear motors
The x stage is provided integrally, and the other is
When the x stage moves, the first drive in the x direction
To move with the x stage by the moving means
Configured, one previous of the mover and the stator of the y linear motors
The y stage is provided integrally, and the other is
When the y stage moves, the first drive in the y direction
Moving with the y stage by the moving means
Positioning stage equipment characterized by being constituted
Place. 10. An x which can reciprocate in the x direction on a guide surface.
A stage and x for driving the x stage in the x direction
First driving means in the direction, and the x stage is moved in the x direction.
X direction with x linear motor that moves by a small amount to
The second driving means and the stator of the x linear motor
Third driving means in the x direction for moving in the x direction
And the y direction orthogonal to the x direction with respect to the x stage
Stage that can reciprocate in the direction
The y-direction driving the y-direction with respect to the x-stage
1 driving means, and the y stage corresponds to the x stage.
Linear motor that moves by a small amount in the y direction
A second driving means in the y direction , comprising:
A third drive in the y direction for moving the stator of the rotor in the y direction.
Moving means, wherein the mover of the x linear motor is integrated with the x stage.
And the stator of the x linear motor is
When the x stage moves, the third position in the x direction
To be moved together with the x stage by a driving means.
And the mover of the y linear motor is integrated with the y stage.
And the stator of the y linear motor is
When the y stage moves, the third position in the y direction
To be moved together with the y stage by a driving means.
Positioning stage device characterized by being constituted
Place. 11. A positioning stage device according to any one of claims 1 to 10, the exposure apparatus characterized by having an exposure means for exposing a substrate supported thereto.