JPH05259022A - Stage mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a stage mechanism in which the stage is elastically coupled to a fixed portion and which can position the stage with high accuracy. [Structure] A linear actuator 4d for driving the stage 4a is held in a movable state with respect to the stage 4a,
The drive position can be adjusted to minimize the rotational displacement of the stage 4a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage mechanism, and more particularly to a stage mechanism capable of fine positioning.

In recent years, as the degree of integration of semiconductor devices has improved, positioning precision and straightness on the order of nanometers have been required for semiconductor manufacturing stages.

In such a stage for performing ultra-precision positioning, it is necessary to develop a fine movement stage having a straightness on the order of nanometer.

[0004]

2. Description of the Related Art FIG. 11 shows a perspective view of a conventional example.

In the figure, 1 indicates a fine movement stage section.

The fine movement stage unit 1 comprises a fine movement stage 1a, a fixed portion 1b, elastic members 1c- _{1 to} 1c _{- 4} , and a linear actuator 1d.

The fixed portion 1b has a U-shape, and the fine movement stage 1a is arranged inside the U-shape of the fixed portion 1b.

The fine movement stage 1a is elastically coupled to the U-shaped inner side surface of the fixed portion 1b by elastic members 1c- _{1 to} 1c _{- 4} which are leaf springs or the like. Further, the fine movement stage 1a is fixed to the fixed portion 1.
It is connected to the linear motion actuator 1d composed of a piezoelectric element or the like at the bottom surface inside the U-shape of b.

[0009]

However, in the conventional stage of this kind, the fine movement stage 1a is positioned by pressing a part of the fine movement stage 1a by the linear movement actuator 1d.

Therefore, in order to obtain the straightness on the order of nanometer, it is necessary to make the rigidity of the elastic members 1c- _{1 to} 1c _{- 4} arranged on the left and right of the fine movement stage 1a exactly the same on the left and right. If strictly when not the same, the displacement of the elastic member 1c _-1 ~1c _-4 respective even under the same force elastic member 1c _-1 ~1c _-4 rigidity of the elastic member 1c _-1 ~1c _-4 left and right Therefore, rotational displacement (yawing) occurs.

FIG. 12 shows a diagram for explaining an operation of a conventional example.

For example, when the rigidity of the elastic members 1c _-3 and 1c _-4 is smaller than the rigidity of the elastic members 1c _-1 and 1c _-2 , when the fine movement stage 1a is driven by the linear motion actuator 1d, the elastic members 1c _-3 , 1c _-4 , a small force is distorted, so that the fine movement stage 1a rotates in the direction of arrow A _{1 as} shown in FIG. Further, when the elastic member 1c _-1, rigidity 1c _-2 fine movement stage 1a is driven by stiffness smaller than the linear actuator 1d of the elastic member 1c _-3, 1c _-4, elastic member 1c _-1, 1c _{- Since 2} is distorted by a small force, it rotates in the direction of arrow A _{2 as} shown in FIG.

However, the elastic members 1c _{-1 to} 1c _-4 are actually used.
When processing the left and right elastic members 1c due to the processing error
_The rigidity differs between _-1 , 1c _-2 and 1c _-3 , 1c _-4 .

Therefore, the fine movement stage 1a is inevitable.
There was a problem that yawing was caused by the movement of, and straightness in the order of nanometer could not be secured.

The present invention has been made in view of the above points, and an object of the present invention is to provide a stage mechanism capable of positioning a stage with high accuracy.

[0016]

According to a first aspect of the present invention, a stage is elastically coupled to a fixed portion by an elastic member, and the stage is linearly moved by a linear actuator in a predetermined direction parallel to the stage surface of the stage. Thus, in the stage mechanism for positioning the stage, the linear motion actuator is configured to be movable and adjustable in a direction parallel to the stage surface and at a right angle to the predetermined direction.

According to a second aspect of the present invention, there is provided a stage mechanism in which the stage is elastically coupled to the fixed portion by an elastic member, and the stage is positioned by moving the stage in a direction parallel to the stage surface of the stage by a linear actuator. , A force generation that applies a force to the stage, is provided on an end surface of the stage facing the linear motion actuator, and is movable in a direction parallel to the stage surface and at a right angle to the driving direction of the linear motion actuator. It is configured to have means.

According to a third aspect of the present invention, there is provided a stage mechanism in which the stage is elastically coupled to the fixed portion by an elastic member, and the stage is positioned by moving the stage in a direction parallel to the stage surface of the stage by a linear actuator. The end surface of the stage facing the linear actuator is parallel to the stage surface, and
The linear actuator is movably provided in a direction perpendicular to the driving direction, and has a plurality of force generating means for applying a force to the stage.

[0019]

In the structure in which the linear motion actuator for moving the fine motion stage according to claim 1 is movable, by moving the driving position of the fine motion stage by the linear motion actuator,
By unbalancing the force acting on the fine movement stage to the left and right, it is possible to compensate for the imbalance in the rigidity of the elastic member.

Therefore, the drive position can be set to a position where the rotational displacement of the fine movement stage is minimized.

Further, in the structure in which the force generating means is movably provided so as to face the linear actuator according to the second aspect, it is possible to correct the imbalance of the rigidity of the elastic member of the fine movement stage by appropriately moving it.

In the structure provided with the plurality of force generating means according to the third aspect, the rotational displacement is reduced by imbalanced the forces generated by the force generating means.

[0023]

1 is a perspective view of a first embodiment of the present invention.
In the figure, 4 indicates a fine movement stage section. Fine movement stage section 4
Is a fine movement stage 4a, a fixed portion 4b, an elastic member 4c_-1~ 4
c _-Four, A linear actuator 4d.

The fixed portion 4b has a U shape, and the fine movement stage 1a is arranged inside the U shape of the fixed portion 4b.

The fine movement stage 1a is made of an elastic material such as a leaf spring.
Member 4c_-1~ 4c_-FourFixed by Figure 4b U-side inside and bullet
Have sex bond. Further, the fine movement stage 4a is fixed to the fixed portion 1b.
Linear actuator consisting of a piezoelectric element, etc. on the bottom of the U-shape
It is combined with 4d. 4a _-1Is the stage surface,
Surface 4a_-1Serves as a mounting surface for a wafer or the like. Straight from the fixed part 4b
The fine movement stage 4 is connected to the moving actuator 4d.
Guide groove 4b parallel to the surface of a_-1Are formed.

FIG. 2 is a sectional view of the essential parts of the first embodiment of the present invention.
Indicates. Guide groove 4b as shown _-1Is a direct acting actu
The convex portion 4d formed on the data 4d_-1Engage. to this
As a result, the linear actuator 4d has a guide groove 4b._-1Along
It is configured to be movable in the X direction.

At this time, screws 6 are provided on both sides of the fixed portion 4b.
a and 6b are threadedly engaged with the fixed portion 4b while penetrating. Both screws 6a and 6b are in the direction of extension of the rotation axis (direction of arrow C).
The linear actuator 4d is brought into contact with the linear actuator 4d, and the linear actuator 4d can be positioned by adjusting the insertion amounts of the screws 6a and 6b.

When the screw 6a is screwed in and the screw 6b is loosened, the linear actuator 4d moves in the arrow X ₁ direction, and when the screw 6a is loosened and the screw 6b is screwed in, it moves in the arrow X ₂ direction.

The fixed portion 4b is fixed to the coarse movement stage 5, and the fine movement stage portion 4 is roughly positioned by the coarse movement stage 5.

Further, the fine movement stage 4a is driven in the direction of arrow Y by the linear movement actuator 4d, and fine positioning is performed.

FIG. 3 is a diagram for explaining the operation of the first embodiment of the present invention. The operation will be described with reference to FIG.

[0032] FIG. 3 (a) elastic members 4c _-1 to 4 when the maximum value drives the linear actuator 4d of the arrow Y ₂ direction
This shows a case where rotational displacement occurs in the direction of arrow E ₁ due to imbalance of c _-4 . The rotational displacement can be known by measuring the fine movement stage 4a with a laser length measuring device, an autocollimator, or the like.

As shown in FIG. 3 (a), when the rotational displacement occurs in the direction of arrow E ₁ , the screw 6a is loosened in the direction of arrow X ₂ and the screw 6b is screwed in the direction of arrow X ₂ to directly fix it. The dynamic actuator 4d is moved in the arrow X ₂ direction.

By moving the linear movement actuator 4d, the position for pressing the fine movement stage 4a is displaced in the direction of arrow X ₂ . The force the pressing position is shifted by the linear actuator 4d F, moment force M ₁ for driving the stage on the side opposite to the arrow E ₁ occurs.

When the rotational displacement in the direction of arrow E ₁ caused by the imbalance of the elastic members 4c _{-1 to} 4c _-4 is corrected by the previous moment force M ₁ , the fine movement stage 4a can be positioned without rotational displacement. ..

The linear actuator 4d is a fine movement stage a.
The rotational displacement of is measured by the above-described laser length measuring device, auto-collimator, etc., and moved to a position where the rotational displacement is minimum.

FIG. 3B shows elastic members 1c _-1 , 1c _-2 , 1
This is a case where the rotational displacement in the direction of arrow E ₂ occurs in the fine movement stage 4a due to the imbalance of the rigidity of c _-3 and 1c _-4 .

FIG. 4 shows a perspective view of the second embodiment of the present invention.

In the figure, numeral 7 indicates a fine movement stage section.

The fine movement stage portion 7 comprises a fine movement stage 7a, a fixed portion 7b, elastic members 7c- _{1 to} 7c _{- 4} , a linear movement actuator 7d, and a pressing member 7e. The fixed portion 7b is formed in a square shape, and the fine movement stage 7a is arranged inside the square shape.
The fine movement stage 7a is elastically coupled to the fixed portion 7b through elastic members 7c- _{1 to} 7c _{- 4} integrally formed with the fine movement stage 7a. 7a _-1 is a stage surface 7a _-1
Positioning is performed with a wafer or the like placed on top.

The fine movement stage 7a and the fixed portion 7b are connected by a linear movement actuator 7d, and the fine movement stage 7a
Is movable in the direction of the arrow Y. At this time, the linear movement actuator 7d is fixed to the center of one side of the fine movement stage 7a.

Further, the fine movement stage 7a and the fixed portion 7b are elastically coupled by a spring 7e.

The spring 7e is manufactured by wire-cut electric discharge machining or the like.

FIG. 5 is a diagram for explaining the operation of the second embodiment of the present invention.

When adjusting the rotational displacement of the fine movement stage 7a, first, the spring 7e is arranged at a substantially central portion of one side of the fine movement stage 7a.

Then, the rotational displacement of the fine movement stage 7a when the fine movement stage 7a is moved to the maximum in the direction of the arrow Y ₁ by the linear movement actuator 7d is measured by a racer length measuring device, an autocollimator or the like.

The rotational displacement is indicated by an arrow H as shown in FIG.
₁Elastic member 7c if the direction is _-1~ 7c_-FourLeft and right of
Due to different rigidity, rotational moment force acts and rotational displacement
Cause

Therefore, by moving the spring 7e in the direction of the arrow X ₁ , a rotational moment force in the opposite direction is generated to reduce the rotational displacement.

Further, as shown in FIG. 5B, when a rotational displacement occurs in the direction of arrow H ₂ , the rigidity of the elastic member is
Since it is the reverse of FIG. 5A, a rotational moment force in the opposite direction acts and rotational displacement occurs.

Therefore, the spring 7e is moved in the direction of the arrow X ₂ to generate a rotational moment force and reduce the rotational displacement.

FIG. 6 shows a perspective view of the third embodiment of the present invention.

In the figure, the same components as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, as means for yawing correction,
Instead of the spring 7e, the magnet 7f_-1, 7f _-2Using magnetic force
It is a thing.

The magnet 7f _-1 is attached to the fixed portion 7b so as to be movable in the direction of arrow G.

Further, the magnet 7F_-2Is the magnetism of the fine movement stage 4a
Stone 7f_-1It is fixed in a position facing. Magnet 7f_-2
Is a magnet 7f_-1It has a long shape in the moving direction of the magnet
7f _-1Magnet 7f even if is moved_-1And the structure that always confronts
Has been done.

The magnets 7f _-1 and 7f _-2 have N poles or S poles facing each other, and these magnets 7f _-1 , 7f _-2
The rotational displacement of the fine movement stage 7a is adjusted by the repulsive force acting by.

In this embodiment, the magnets 7f _-1 and 7f _-2 have N poles facing each other and a repulsive force is generated, but the N poles and S poles face each other. The rotational displacement may be adjusted by the suction force. However, in this case, it is necessary to adjust the moving direction of the magnet 7f _{-1 in} the opposite direction to the case of adjusting the moving direction by the repulsive force.

FIG. 7 shows a perspective view of the fourth embodiment of the present invention. In the figure, the same components as those in FIG.
The description is omitted.

In this embodiment, the rotational displacement is adjusted by a plurality of springs 7g _-1 , 7g _-2.
g ₋₁ and 7g ₋₂ are fixed at predetermined positions with an equal interval from the center of the side between the fixed portion 7b and the fine movement stage 7a.

The springs 7g _-1 , 7g _-2 are set such that the spring constants of the springs 7g _-1 and 7g _-2 are minimized in terms of rotational displacement before they are fixed in place.

[0061] For example, when the rotational displacement in the arrow I ₁ direction arises spring constant used spring 7 g _-1 greater than the spring constant of the spring 7 g _-2.

[0062] When the resulting rotation displaced in the arrow I ₂ direction, the spring constant is used spring 7 g _-1 smaller than the spring constant of the spring 7 g _-2.

FIG. 8 shows a perspective view of the fifth embodiment of the present invention. In the figure, the same components as those of FIG.
The description is omitted.

In this embodiment, the springs are changed to 7g _-1 , 7g _-2 ,
Air springs 7h _-1 , 7h _-2 are used.
_-1 , 7h _-2 are connected to the compressor 9 and the like via pipes 7i _-1 , 7i _-2 .

In this embodiment, the air pressure of the air springs 7h _-1 , 7h _-2 is adjusted by the compressor 9 to adjust the spring constants of the air springs 7h _-1 , 7h _-2 to minimize the rotational displacement.

For example, when rotational displacement occurs in the direction of arrow I ₁ , the pressure V ₁ of the air spring 7h _-1 is applied by the compressor 9
Is made larger than the pressure V ₂ of the air spring 7h _-2 , and (V ₁ > V
₂₎ the spring constant of the air spring 7h _-1 larger than the spring constant of the air spring 7h _-2.

When a rotational displacement occurs in the direction of arrow I ₂ , the compressor 9 causes the pressure V ₁ of the air spring 7h _-1 to increase.
Is less than the pressure V ₂ of the air spring 7h _-2 (V ₁ <
V ₂ ) The spring constant is made smaller than the spring constant of the air spring 7h _-2 .

In this embodiment, the pressure (spring constant) of the air springs 7h _-1 , 7h _-2 can be easily changed from the outside by the regulator connected to the compressor 9, and the adjustment can be easily performed.

FIG. 9 shows a perspective view of the sixth embodiment of the present invention. In the figure, the same components as those in FIG.
The description is omitted.

In this embodiment, the air springs 7h _-1 , 7h _-2 shown in FIG. 8 are used.
Are replaced by voice coil motors (VCM) 7i _-1 , 7i _-2 . FIG. 9 shows a perspective view of the voice coil motor.

[0071] The voice coil motor 7i _-1 includes a yoke 7i _-11 to form a magnetic circuit, the magnets 7i _-12 fixed to the inner peripheral portion of the yoke 7i _-11, engaged to be movable in the yoke 7i within _-11 Coil 7i _-13 , coil 7i
By supplying a drive current to the coil _-13 by the drive circuit 10, the coil 7i- ₁₃ is driven in the direction of the arrow Y.

The voice coil motor 7i _-2 has the same structure as the voice coil motor 7i _-1, and a driving force corresponding to the driving current from the driving circuit 10 is applied in the arrow Y direction.

In this embodiment, similarly to the fifth embodiment, the driving force of the voice coil motors 7i _-1 , 7i _-2 can be easily changed according to the driving current from the driving circuit 10 provided outside. Therefore, adjustment can be easily performed.

[0074]

As described above, according to the invention of claim 1,
The rotational displacement of the stage caused by a processing error or the like can move the driving position of the stage by moving the position of the linear motion actuator, so that a rotational moment force can be generated in the fine motion stage. Therefore, the rotational displacement can be minimized, and the yawing of the stage can be reduced.

According to the second aspect of the invention, since the moment generating force can be applied to the stage by the force generating means, the rotational displacement can be minimized and the yawing of the stage can be reduced. Moreover, the linear actuator has the feature that it can be adjusted while it is fixed.

According to the third aspect of the invention, since the forces acting on the stage can be balanced by the plurality of force generating means, the rotational displacement can be minimized even with the existing stage mechanism, and the yawing of the stage can be reduced. it can.
Further, it has a feature that adjustment can be performed while fixing the linear motion actuator and the force generating means.

[Brief description of drawings]

FIG. 1 is a perspective view of a first embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II of the first embodiment of the present invention.

FIG. 3 is a diagram for explaining the operation of the first exemplary embodiment of the present invention.

FIG. 4 is a perspective view of a second embodiment of the present invention.

FIG. 5 is a diagram for explaining the operation of the second embodiment of the present invention.

FIG. 6 is a perspective view of a third embodiment of the present invention.

FIG. 7 is a perspective view of a fourth embodiment of the present invention.

FIG. 8 is a perspective view of a fifth embodiment of the present invention.

FIG. 9 is a perspective view of a sixth embodiment of the present invention.

FIG. 10 is a perspective view of a main part of a sixth embodiment of the present invention.

FIG. 11 is a perspective view of a conventional example.

FIG. 12 is a diagram for explaining an operation of a conventional example.

[Explanation of symbols]

4 Fine movement stage part 4a Fine movement stage 4b Fixed part 4c- _{1 to} 4c _{- 4} Elastic member 4d Linear motion actuator 5 Coarse movement stage part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Sakata 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (3)

[Claims] 1. The stage (4a) is provided with an elastic member (4c _-1 ~).
4c _-4 ) and elastically coupled to the fixed part (4b),
The stage (4a) is driven by the linear actuator (4d), and the stage surface (4) of the stage (4a) is accompanied by elastic deformation of the elastic members (4c- _{1 to} 4c _{- 4} ).
a _-1 ) in a stage mechanism that linearly moves in a predetermined direction (Y) parallel to the linear movement actuator (4d).
a _-1 ) and a structure capable of moving and adjusting in a direction (X) perpendicular to the predetermined direction (Y) and parallel to a _-1 ). 2. The elastic member (7c _-1 ~) for the stage (7a).
7c _-4 ) and elastically coupled to the fixed part (7b),
The stage (7a) is driven by the linear actuator (7d), and the stage surface (4) of the stage (4a) is accompanied by elastic deformation of the elastic members (7c- _{1 to} 7c _{- 4} ).
a ₋₁ ), the stage mechanism for linearly moving in a direction parallel to
a), the stage surface (7a
_-1 ), and is provided so as to be movable in a direction perpendicular to the driving direction of the actuator (7d), and has a force generating means (7e) for applying a force to the stage (7a). Stage mechanism to do. 3. The stage (7a) is provided with an elastic member (7c _-1 ~).
7c _-4 ) and elastically coupled to the fixed part (7b),
A stage mechanism for positioning the stage (4a) by moving the stage (7a) in a direction parallel to the stage surface of the stage (4a) by the linear actuator (7d), wherein the linear actuator (7d) To the stage (7
a) is provided so as to face each other across the stage (7a _-1 ) and is movable in a direction perpendicular to the driving direction of the linear actuator (7d). Multiple force generating means for applying force (7g _-1 , 7g
_-2 ; 7h _-1 , 7h _-2 ; 7i _-1 , 7i _-2 ).