JP2003197518A - Exposure system and exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure system which is capable of exposing a pattern while the system keeps its center of gravity stationary. <P>SOLUTION: Above a projection optical device (PL), a reticle stage (14) and a counterweight (22) are actuated by drive means (54) and (56) to move in opposite directions respectively in the direction of a first axis. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable stage device capable of accurately moving, and more particularly, to a movable stage device.
With respect to a stage device that is movable in one linear direction and is capable of high-accuracy positioning and high-speed movement, such a stage device is particularly preferably used in microlithographic devices.

[0002]

2. Description of the Prior Art In wafer steppers, the alignment of the exposure field with respect to the reticle being imaged affects the performance of the circuitry exposed within that field. In a scanning exposure apparatus, the reticle and the wafer move simultaneously and scan each other during the exposure sequence. The present invention discloses, for such a device, a device for performing a precise scanning movement.

To obtain high accuracy, the stage must be insulated from mechanical disturbances. This is done by positioning and moving the stage using electromagnetic force.
To be achieved. A high control bandwidth is also required, which requires the stage to be lightweight and the stage to have no moving parts. In addition, the stage must not generate excessive heat that may interfere with interferometer measurements or mechanical changes that reduce alignment accuracy.

US Pat. Nos. 4,506,204, 4,
Non-rectifying electromagnetic alignment devices, such as those disclosed in Nos. 506,205 and 4,507,597, are not economical because such electromagnetic alignment devices are not commercially available. This is because it is necessary to manufacture such an assembly composed of a large magnet and a coil. The weight of the stage and the heat generated also make such designs unsuitable for high precision applications.

An improvement over a commutatorless device such as the one described above is disclosed in US Pat. No. 4,952,858, which mechanically provides a large displacement movement in the plane, in the XY directions. A guided, conventional sub-stage is used, which eliminates the need for a large magnet and coil assembly. Electromagnetic means provided on the sub-stage insulates the stage from mechanical disturbances. However, the combined weight of the substage and the stage still results in a low control bandwidth and the heat generated by the electromagnetic elements supporting the stage is still substantial.

Common devices using rectifying type electromagnetic means show a considerable improvement over prior art non-commutator type means, but with low control bandwidth and interferometer interference problems. Still remains. In such a device, the sub-stage is moved in one linear direction using electromagnetic force, while rectifying-type electromagnetic means provided in the sub-stage move the stage in its orthogonal direction. The sub-stage is heavy because it carries a magnetic orbit to move the stage. Also, heat dissipation on the stage reduces the accuracy of the interferometer.

In addition, two parallel coils, each consisting of a coil and a magnet,
It is known to use two linear motors to move a movable member (stage) in a long (eg longer than 10 cm) linear direction. In this case, the stage is guided by a linear guide member of some kind, and is driven in a straight line direction by a linear motor provided parallel to the guide member. When driving the stage over a very small stroke range, a guideless structure based on a composite of several electromagnetic actuators can be employed, as disclosed in the above-mentioned prior art. However, in order to move the guideless stage a long distance in a certain linear direction, as in the prior art, a specially constructed electromagnetic actuator is required, which increases the size of the device, resulting in a larger power consumption. The problem of consumption arises.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to use an electromagnetic force to move a guideless stage in the direction of a long linear movement, and to achieve a small inertial force and a high response, which is lightweight. Is to provide the device.

Another object of the present invention is to provide a guideless stage device using a commercially available ordinary linear motor as an electromagnetic actuator for performing one linear movement.

Another object of the present invention is to provide a guideless stage device capable of actively and accurately performing positioning control over a small displacement without making contact in a direction orthogonal to the long linear motion direction. Is to provide.

Further, an object of the present invention is to provide a movable member (stage body) which moves in one linear direction and a first movable member which moves sequentially in the same direction and constantly maintains a constant space between the movable member and the moving member. While providing two movable members,
Electromagnetic force (acting force and reaction force) in a direction orthogonal to the linear direction between the second movable member and the stage body.
Is to provide a completely non-contact type stage device.

Another object of the present invention is to improve positioning and traveling accuracy because tensions of various cables (electric wires) and tubes connected to a non-contact type stage body that moves while supporting an object are changed. It is an object of the present invention to provide a non-contact type stage device capable of preventing the deterioration.

Another object of the present invention is to arrange a first movable member and a second movable member in parallel, and to arrange the first movable member and the second movable member in mutually opposite linear directions. The object is to provide a non-contact type device having a low height by being moved. Further, it is an object of the present invention to provide a device in which the non-contact type stage main body is configured so that the position of the center of gravity of the entire device does not change even if it moves in a certain linear direction.

[0014]

In order to solve the above-mentioned problems, an explanation will be given with reference to the drawings showing an embodiment, in which the exposure apparatus according to claim 1 has each linear motor (54A, 54A,
56A, 54B, 56B) one member (56A, 56B)
When the counterweight (22) carrying B) is suspended on the base structure (12) and an acting force for moving the stage in the first direction is given on the base structure (12), the counterweight (22) acts on the acting force. Accordingly, the center of gravity is maintained by moving in the opposite direction, and the stage is the reticle stage of the exposure apparatus that exposes the pattern of the reticle (44) onto the substrate. The stage is below the reticle stage (12) and the counterweight (22). A projection optical device (PL) for projecting the pattern of the reticle (44) provided on the substrate is provided.

An exposure apparatus according to a second aspect includes a reticle stage (14) that linearly moves in at least a first direction on a reference surface, and a pattern of a reticle (44) held by the reticle stage (14). An exposure device for exposing a substrate to a substrate, (a) a counterweight (22) provided adjacent to a side portion of the reticle stage (14) and movable in a first direction; A first magnetizing member (54A, 54B) provided on the reticle stage (14) and a second magnetizing member (56) provided on the counterweight (22) so as to generate a driving force toward the first direction.
A, 56B), which is provided below the drive means (54, 56) for electromagnetically driving the reticle stage (14), and (c) the reticle stage (14) and the counterweight (22). A projection optical device (PL) for projecting the pattern onto the substrate, and by driving the driving means (54, 56) above the projection optical device (PL),
Reticle stage (14) and counterweight (2
2) and 2) are moving in the opposite directions in the first direction.

According to a third aspect of the exposure apparatus, the base structure (1) has a reference plane provided above the projection optical apparatus (PL).
It is formed in 2). The exposure apparatus according to claim 4, wherein the reticle stage (14) moves above the reference surface via the first fluid bearing (48), and the counterweight (22) is at a position different from the first fluid bearing (48). Second provided in
It is moving via a fluid bearing (32).

In the exposure apparatus according to the fifth aspect, the counterweight (22) moves on the reference plane. Claim 6
In the described exposure apparatus, one of the first magnetizing member and the second magnetizing member is a coil (54A, 54B), and the other of the first magnetizing member and the second magnetizing member is a magnet (56A, 56B).

An exposure apparatus according to claim 7 is a laser interferometer apparatus (1) for detecting the position of a reticle stage (14).
5) is provided. In the exposure apparatus according to the eighth aspect, the driving means (54, 56) corrects the yawing of the reticle stage (14).

In the exposure apparatus according to the ninth aspect, the drive means has a pair of drive assemblies (54A, 56A, 54B, 54).
B). The exposure apparatus according to claim 10, wherein the counterweight (22) has an arm (2) along the first direction.
6).

In the exposure apparatus according to the eleventh aspect, the counterweight (22) has a rectangular shape. The exposure apparatus according to claim 12 is provided with a linear motor for adjusting the position of the counterweight (22).

In the exposure apparatus according to the thirteenth aspect, the reticle (44) is moved while the reticle stage (14) is being scanned.
Is a scanning type exposure apparatus that exposes the pattern of FIG. The exposure method according to claim 14 includes a reticle stage (14) that linearly moves in at least a first direction on a reference surface, and a pattern of a reticle (44) held by the reticle stage (14). And a second magnetizing member (56A, 5B) provided on the reticle stage (14) and a second magnetizing member (56A, 5B).
6B), and the step of providing drive means (54, 56) for moving the reticle stage (14) in the first direction, and the excitation of the drive means (54, 56), the reticle stage (14) and the second A step of moving the counterweight (22) provided with the magnetizing members (56A, 56B) in opposite directions in the first direction, and a projection provided below the reticle stage (14) and the counterweight (22). The reticle (4
4) projecting the pattern on the substrate.

In an exposure method according to a fifteenth aspect, a base structure (1) in which a reference plane is provided above the projection optical device (PL).
It is formed in 2). The exposure method according to claim 16,
A step of moving the reticle stage (14) on the reference surface via the first fluid bearing (48), and a second fluid provided with the counterweight (22) at a position different from that of the first fluid bearing (48). The step of moving through a bearing (32) is included.

In the exposure method according to the seventeenth aspect, the counterweight (22) moves on the reference surface. Claim 18
In the described exposure method, one of the first magnetizing member and the second magnetizing member is a coil (54A, 54B), and the other of the first magnetizing member and the second magnetizing member is a magnet (56A, 56B).

An exposure method according to a nineteenth aspect includes the step of detecting the position of the reticle stage (14) by the laser interferometer device (15). An exposure method according to a twentieth aspect includes a step of correcting yawing of the reticle stage (14) by the driving means (54, 56).

In the exposure method according to the twenty-first aspect, the drive means is a pair of drive assemblies (54A, 56A, 54B, 56).
B). The exposure method according to claim 22, wherein the counterweight (22) has an arm (2) extending in the first direction.
6).

In the exposure method according to the twenty-third aspect, the counterweight (22) has a rectangular shape. The exposure method according to claim 24 includes a step of adjusting the position of the counterweight (22) by a linear motor. Claim 2
In the exposure method described in No. 5, the pattern of the reticle (44) is exposed on the substrate while the reticle stage (14) is being scanned. In the exposure apparatus according to claim 26, the reticle stage (14) is a guideless stage.

Other objects and features of the present invention will become more apparent upon reading the following description, with reference to the drawings, wherein like reference numerals refer to like elements throughout.

[0028]

The exposure apparatus according to claim 1 is a projection optical apparatus (P
Above L), the reticle stage (14) and the counterweight (22) move in opposite directions in the first direction due to the excitation of the driving means (54, 56), so that the center of gravity of the device is maintained. In this state, the projection optical apparatus (PL) can expose the pattern of the reticle (44) on the substrate. The exposure apparatus according to claim 2 is a driving means (54, 5) above the projection optical apparatus (PL).
Since the reticle stage (14) and the counterweight (22) move in the opposite directions in the first direction by the excitation of 6), the projection optical apparatus (PL) moves the reticle while the center of gravity of the apparatus is maintained. The pattern of (44) can be exposed on the substrate.

The exposure apparatus according to the third aspect can prevent the center of gravity from moving above the base structure (12). The exposure apparatus according to claim 4, wherein the reticle stage (14) moves above the reference surface with a gap by the first fluid bearing (48), and the counterweight (22) forms a gap by the second fluid bearing (32). Have moved.

In the exposure apparatus according to the fifth aspect, the reticle stage (14) and the counterweight (22) move on the reference plane. In the exposure apparatus according to the sixth aspect, the reticle stage (14) is moved in the first direction by using the coils (54A, 54B) and the magnets (56A, 56B).

In the exposure apparatus according to the seventh aspect, the laser interferometer device (15) detects the position of the reticle stage (14). The exposure apparatus according to claim 8 is a driving means (5
4, 56) can correct the yawing of the reticle stage (14).

In the exposure apparatus according to the ninth aspect, the pair of drive assemblies (54A, 56A, 54B, 54B) move the reticle stage (14) in the first direction. The exposure apparatus according to claim 10 is an arm (2) extending in the first direction.
The counterweight (22) can be constituted by 6).

In the exposure apparatus according to the eleventh aspect, the counterweight (22) can be constituted by a rectangular member. In the exposure apparatus according to the twelfth aspect, the position of the counterweight (22) can be adjusted by the linear motor.

The exposure apparatus according to the thirteenth aspect can maintain the position of the center of gravity of the reticle stage (14) during scanning exposure. The exposure method according to claim 14, wherein the reticle stage (14) and the counterweight (22) are opposite to each other in the first direction above the projection optical device (PL) by the excitation of the driving means (54, 56). Since it is moving in the direction, the projection optical device (PL) can expose the pattern of the reticle (44) onto the substrate while maintaining the center of gravity of the device.

The exposure method according to the fifteenth aspect can prevent the center of gravity from moving above the base structure (12). The exposure method according to claim 16, wherein the reticle stage (14) moves above the reference plane with a gap by the first fluid bearing (48), and the counterweight (22) forms a gap by the second fluid bearing (32). Have moved.

In the exposure method according to the seventeenth aspect, the reticle stage (14) and the counterweight (22) move on the reference plane. The exposure method according to claim 18,
The coils (54A, 54B) and the magnets (56A, 56B) are used to move the reticle stage (14) in the first direction.

In the exposure method according to the nineteenth aspect, the laser interferometer device (15) detects the position of the reticle stage (14). In the exposure method according to claim 20, yawing of the reticle stage (14) can be corrected by the driving means (54, 56).

In the exposure method according to the twenty-first aspect, the pair of drive assemblies (54A, 56A, 54B, 54B) move the reticle stage (14) in the first direction. The exposure method according to claim 22, wherein the arm (2
6) is the counterweight (22).

In the exposure method according to the twenty-third aspect, a rectangular counterweight (22) is used. In the exposure method according to the twenty-fourth aspect, the position of the counterweight (22) can be adjusted by the linear motor. In the exposure method according to claim 25, the position of the center of gravity of the reticle stage (14) during the scanning exposure can be maintained. In the exposure apparatus according to the twenty-sixth aspect, since the reticle stage (14) is a guideless stage, a high control band can be obtained.

[0040]

In order to achieve the above-mentioned main object, the present invention is configured to have the following features. An apparatus capable of performing highly accurate position and movement control is disclosed below. The apparatus uses a rectifying type linear motor to move the guideless stage in one long straight direction in a certain plane and to perform a small yaw rotation. Carrier / holding a single voice coil motor (VCM)
A follower is controlled to generally follow the stage in the direction of the long linear motion. The above VCM is
An electromagnetic force is caused to move the stage by a small distance in the plane in a linear direction orthogonal to the direction of the long linear motion. The design of the follower is
Eliminates the problem of cable drag on the stage,
The reason is that the cable connected to the stage follows the stage via the carrier / follower. The cable connecting the carrier / follower to an external device will have some amount of drag, but the stage is not subject to such external influences (external causes) because the carrier / follower on This is because the VCM acts as a buffer by blocking the transmission of mechanical disturbance to the stage.

As a special feature of the present invention, rectification type linear motors are provided on both sides of the stage and attached to the drive frame. Each of the rectifying linear motors includes a coil member and a magnet member, one of these members is attached to one of both sides of the stage, and the other of the members is attached to a drive frame. . Both motors are driven in the same direction. By driving these motors a slightly different distance, a slight yaw rotation of the stage occurs.

According to another feature of the invention, a movable counterweight is provided so that the momentum conservation law is used to maintain the position of the center of gravity of the stage apparatus during movement of the stage. In one embodiment of the present invention, a drive frame carrying one member of each linear motor is suspended above the base structure and a drive assembly moves the stage one way above the base structure. Upon application of a force, the drive frame, in response to its reaction force, moves in opposite directions, thereby substantially maintaining the center of gravity of the device. The device substantially eliminates the reaction force between the stage device and the base structure on which it is provided, which allows a large acceleration force and very little vibration effects on the device. To do.

By limiting the movement of the stage to three specific degrees of freedom, the device is simplified. By using off-the-shelf electromagnetic components, the device design can be easily adapted to changes in stage dimensions. This high-precision positioning device is ideal for use as a reticle scanner of a scanning exposure device, and provides a smooth and accurate scanning movement in a certain linear direction, and
By controlling a small displacement movement in the direction orthogonal to the scanning direction and a small yaw rotation amount in the plane, accurate alignment is surely performed. Although the present invention is generally applicable to electromagnetic alignment devices, the preferred embodiment includes the reticle stage scanning device shown in FIGS. Referring now to the drawings,
The positioning device 10 of the present invention includes a base structure 12, on which a reticle stage 14 is suspended so as to move as desired, a laser interferometer device 15 for tracking the position of the reticle stage, and a position sensor 13. , C
The position control device 16 operated by the PU 16 '(see FIG. 8).

The elongated positioning guide 17 is provided on the base 12.
A support bracket 18 (two brackets in the illustrated embodiment) is movably supported on the guide 17 by, for example, an air bearing 20. The support bracket 18 is connected to a drive assembly 22 or drive frame in the form of a magnetic track assembly for moving and slightly yawing the reticle stage 14 in the X direction. This drive frame comprises a pair of magnetic orbital arms 2 which are spaced in parallel.
4, 26, which are connected to each other by transverse arms 28, 30 to form an open rectangular body. In the preferred embodiment, the drive frame 22 is movably supported on the base structure 12, for example by means of air bearings 32, whereby the frame is supported on the base structure on the guide 1.
It is free to move in a direction along the longitudinal axis of 7. This direction is the principal axis direction in which the scanning movement of the reticle stage is required. "One direction" as used herein
Alternatively, the “first direction” means that the frame 22 or the reticle stage 14 is X-axis along the longitudinal axis of the guide 17.
In a direction, it means to move forward or backward.

Next, further explaining with reference to FIGS. 1 and 7, a guide member or guide member 17 elongated in the X direction is provided.
Has front and rear guide surfaces 17A, 17B, which are generally orthogonal to the surface 12A of the base structure 12. The front guide surface 17A faces the rectangular drive frame 22 and guides the air bearing 20 fixed inside the support bracket 18. The support bracket 18 is attached to each end of the upper surface of the arm 24 parallel to the guide member of the drive frame 22. Also, each support bracket 18 is
The guide member 17 is formed in a hook shape and is arranged in the Y direction.
And its free end faces the rear guide surface 17B on the rear side of the guide member 17. The air bearing 20 '
It is fixed inside the free end of the support bracket 18 and faces the rear guide surface 17B. Therefore, the movement of each of the support brackets 18 in the Y direction is restricted by the guide member 17 and the air bearings 20 and 20 ', and can be moved only in the X direction.

Next, according to the first embodiment of the present invention, the air bearings 32 fixed to the bottom surfaces of the four rectangular parts of the drive frame 22 form an air layer, and the pad surface and the base structure 12 are formed. Has a constant gap, that is, a gap (1 μm to less than several μm) from the surface 12A of the. The drive frame is levitated from the surface 12A by the air layer and is supported in the vertical direction (Z direction). As will be described in detail later, in FIG. 1, the carrier / follower 60 located above the upper portion of the elongated arm 24 has a bracket 6 facing both surfaces 17A, 17B of the guide member 17.
It is supported in the lateral direction (Y direction) by the air bearings 66A, 66B supported by 2, and in the vertical direction (Z direction) above the surface 12A of the base structure 12. Therefore, the carrier / follower 60
Are supported so as not to come into contact with any part of the drive frame 22. Therefore, the drive frame 22 is
It is guided from the side by the guide member 17 above the surface 12A of the base and moves linearly only in the X direction.

Next, the structure of the reticle stage 14 and the drive frame 22 will be described with reference to FIGS. The reticle stage 14 includes a main body 42, and a reticle 44 is provided above an opening 46 of the main body.
Is provided. The reticle body 42 includes a pair of opposing side portions 42A and 42B, and is placed and suspended above the base structure 12 by, for example, an air bearing 48. A plurality of interferometer mirrors 50 are provided on the main body 42 of the reticle stage 14, and the interferometer mirrors are the position sensing device 15 of the laser interferometer (see FIG. 8).
Work together to determine the precise position of the reticle stage provided to the position controller 16 and thereby derive the proper drive signal to move the reticle stage 14 as desired.

The basic movement of reticle stage 14 is accomplished by means of a first electromagnetic drive assembly, ie, in the form of a separate drive assembly 52A, 52B provided on each of the opposite sides 42A, 42B. Be seen. The drive assemblies 52A, 52B include drive coils 54A, 54B fixed to the side portions 42A, 42B of the reticle stage 14, respectively, which drive coils are magnetic orbit 56A of the magnetic orbit arms 24, 26 of the drive frame 22. , 56B. In a preferred embodiment of the present invention, the magnetic coil comprises a drive frame 2
2, but the arrangement of such elements of the electromagnetic drive assembly 52 can be reversed.

Now, the structure of the reticle stage 14 will be described in more detail. As shown in FIG. 1, the stage main body 42 is mounted so as to be movable in the Y direction within a rectangular space in the drive frame 22. Stage body 42
Air bearings 4 fixed under each of the four corners of the
8 forms an extremely small air gap between the pad surface and the surface 12A of the base, and suspends and supports the entire stage 14 from the surface 12A. The air gap 48 is preferably of the preload type, which has a recess for performing vacuum suction on the surface 12A.

As shown in FIG. 2, a rectangular opening 46 is provided in the center of the stage body 42, so that the projected image of the pattern formed on the reticle 44 can pass through the opening. The projected image has a rectangular opening 46.
Another opening 12B is provided in the central portion of the base structure 12 so that the projection optical apparatus PL (see FIG. 7) provided below the rectangular opening can pass therethrough. The reticle 44 is clamped by the clamp member 42C.
The clamp member is mounted on the surface of the stage body and is adsorbed by vacuum pressure.
6 are provided so as to project at four points around the circumference.

Next, in the vicinity of the arm 26, the stage main body 42
The interferometer mirror 50Y, which is fixed adjacent to the side portion 42B of the interferometer, has an elongated vertical reflecting surface in the X direction, and the length of the interferometer mirror is the movement of the stage 14 in the X direction. The laser beam LBY from the Y-axis interferometer is made to be orthogonal to the reflecting surface and is slightly longer than the stroke. In FIG. 2, the laser beam LBY
Is bent at a right angle by a mirror 12D fixed to the side of the base structure 12.

Referring to FIG. 3, which is a partial cross-sectional view taken along line 3-3 of FIG. 2, the laser beam LBY incident on the reflecting surface of the interferometer mirror 50Y is a bottom surface of the reticle 44 attached to the clamp member 42C. It is placed in the same plane as (the surface on which the pattern is formed). 3 also shows the air bearing 20 acting on the end surface of the support bracket 18 facing the guide surface 17B of the guide member 17.

Referring again to FIGS. 1 and 2, the laser beam LBX1 from the X1 axis interferometer is incident and reflected by the interferometer mirror 50X1. Further, the laser beam LBX2 from the X2-axis interferometer is incident on the interferometer mirror 50.
Reflect at X2. These two mirrors 50X1, 50X
2 is configured as a corner cube type mirror, and the mirror always keeps the incident axis and the reflection axis of the laser beam parallel to each other in the XY plane even when the stage 14 performs yaw rotation. Also, block 12C of FIG.
Is the laser beam LBX1, LBX2 for each mirror 5
An optical block such as a prism for directing 0X1, 50X2, which is fixed to a component of the base structure 12. Corresponding blocks for the LBY laser beam are not shown.

In FIG. 2, two laser beams LB are shown.
The distance BL in the Y direction between the center lines of X1 and LBX2 is the length of the reference line used for calculating the amount of yaw rotation, that is, the amount of yaw rotation. Therefore, the difference between the measurement value ΔX1 in the X direction of the X1 axis interferometer and the measurement value ΔX2 in the X direction of the X2 axis interferometer divided by the length BL of the reference line is a yaw value in a very small range. It is almost equal to the amount of rotation. A half value of the sum of ΔX1 and ΔX2 represents the X coordinate position of the entire stage 14.
These calculations are performed by the high speed digital processor of the position controller 16 shown in FIG.

Further, each of the laser beams LBX1 and LB
The center line of X2 is set on the same surface as the surface on which the pattern is formed on the reticle 44. Laser beam LBX
1. The extension line of the line GX shown in FIG. 2 and the extension line of the laser beam LBY, which divide the space between the center lines of the LBX2 into halves, are in the same surface on which the pattern is formed. Cross at. Further, the optical axis AX (see FIGS. 1 and 7) also passes through the intersection as shown in FIG.
In FIG. 1, a slit-shaped irradiation field ILS including the optical axis AX is shown on the reticle 44, and the pattern image of the reticle 44 is scanned and exposed via the projection optical device PL. Is exposed to a transparent substrate.

1 and 2, the stage body 4 is shown.
Two rectangular blocks 9 fixed to the second side portion 42A
0A and 90B are provided. These blocks 90
A and 90B receive the driving force in the Y direction from the second electromagnetic actuator 70 attached to the carrier / follower 60. Details will be described later.

The drive coils 54A and 54B fixed to both sides of the stage body 42 are formed flat and parallel to the XY plane, and the magnetic fluxes of the slots extending in the X direction of the magnetic tracks 56A and 56B without contact. Exercise in space.
The drive coil 54 and magnetic track 56 assembly used in this example is a commercially available, readily available, general-purpose linear motor with or without a commutator. .

Here, in consideration of the actual design, the moving stroke of the reticle stage 14 is roughly the same as that of the reticle 4.
4 size (the amount of movement required when performing a scan for exposure, and the amount of movement required when removing the reticle from the illumination optics to replace the reticle). In this example, the travel stroke is about 30 cm when using a 6 inch reticle. As described above, the drive frame 2
2 and the stage 14 are independently levitated and supported on the surface 12A of the base, while at the same time magnetic action and reaction force
Only the linear motors 52 act on each other in the X direction. Thereby, the law of conservation of momentum works between the drive frame 22 and the stage 14.

Next, assuming that the total weight of the reticle stage 14 is about one fifth of the total weight of the frame 22 including the support bracket 18, a forward movement of 30 cm in the X direction of the stage 14 causes the drive frame 22 to move. Is retracted in the X direction by 6 cm. This means that the position of the center of gravity of the device on the base structure 12 is substantially fixed in the X direction. In the Y direction,
Objects with large weight do not move. Therefore, the variation of the position of the center of gravity in the Y direction is relatively small.

Although the stage 14 can move in the X direction as described above, the moving coils (54A, 54A)
B) and the stator of the linear motor 52 interfere (collide) with each other in the Y direction when there is no actuator in the X direction. Therefore, the carrier / follower 60 and the second electromagnetic actuator 70, which are characteristic components of the present invention, are provided to control the stage 14 in the Y direction.

Next, the structure will be described with reference to FIGS. 1, 2, 3 and 7. As shown in FIG. 1, the carrier / follower 60 is movably mounted in the Y direction by a hook-shaped support bracket 62 that straddles the guide member 17. Further, as is apparent from FIG. 2, the carrier / follower 60 is provided above the arm 24 and maintains a certain space between the stage 14 (main body 42) and the arm 24. Carrier / Follower 6
One end portion 60E of 0 projects substantially inward (toward the stage body 42) above the arm 24. In this end part, the drive coil 68 (same shape as the coil 54) that enters the space of the slot of the magnetic track 56A is fixed.

Further, the air bearing 66A (see FIGS. 2, 3, 4 and 7) supported by the bracket 62 and facing the guide surface 17A of the guide member 17 is guided by the carrier / follower 60. It is fixed in the space between the member and the arm 24. An air bearing 66 that levitates the carrier / follower 60 to support it above the surface 12A of the base is also shown in FIG.

The air bearing 66B in contact with the guide surface 17B of the guide member 17 is also fixed to the free end of the support bracket 62 provided on the side of the hook opposite to the air bearing 66A, and the air bearings 66A and 66B are provided. The guide member 17 is located between and.

Next, as is apparent from FIG. 7, the carrier / follower 60 has the magnetic track 56A and the stage body 42.
, Are arranged so as to maintain a certain space in each of the Y direction and the Z direction. FIG. 7 shows the projection optical device PL and a column rod CB for supporting the base structure 12 above the projection optical device PL. Such a structure is common for projection aligners, where the unwanted movement of the center of gravity of the structure above the base structure 12 causes a lateral offset between the column rod CB and the projection optics PL. Can occur, thus causing image distortion on the photosensitive substrate during exposure. Therefore, the advantage of a device such as this embodiment in that movement of the stage 14 does not move the center of gravity above the base structure 12 is significant.

The structure of the carrier / follower will be described with reference to FIG. In FIG. 4, in order to facilitate understanding, the carrier / follower 60 has two parts 60A,
It is disassembled into 60B. As is apparent from FIG. 4, the drive coil 6 that moves the carrier / follower 60 itself in the X direction.
8 is fixed to the lower portion of the end portion 60E of the carrier / follower 60. Further, an air bearing 66C faces the base structure 12A on the bottom surface of the end 60E and serves to levitate the carrier / follower 60.

Therefore, the carrier / follower 60 is supported in the Z direction by three points of two air bearings 66 and one air bearing 66C, and the air bearing 66A,
The movement in the Y direction is restricted by 66B, and the movement in the X direction is possible. The important point in this construction is that the second magnetic orbital arm 70 is arranged in back-to-back relationship with the support bracket 62, and
When the actuator generates a driving force in the Y direction,
The reaction force in the Y direction between the stage 14 and the carrier / follower 60 positively acts on the air bearings 66A and 66B fixed in the support bracket 62. In other words, the actuator 70 and the air bearings 66A, 6A
Providing 6B on a line parallel to the Y-axis in the XY plane creates undesirable stresses that can mechanically deform the carrier / follower 60 when the actuator 70 'is operating. Prevent from doing. Conversely,
This means that the weight of the carrier / follower 60 can be reduced.

As is apparent from FIGS. 2, 4 and 6 described above, the magnetic track 56A in the arm 24 in the form of the drive frame 22 is relative to the drive coil 54A on the side of the stage body 42. It provides a magnetic flux and, at the same time, a magnetic flux to the drive coil 68 for the carrier / follower 60. For the air bearings 66A, 66B, 66C, vacuum preload type is preferable, because the carrier / follower 60 becomes lighter. A magnetic preload type can also be used instead of the vacuum preload type.

Next, the second actuator provided on the carrier / follower 60 will be described with reference to FIGS. 3, 5 and 7. A second electromagnetic drive assembly in the form of a voice coil motor 70 includes a voice coil 74 mounted on the main body 42 of the reticle stage 14 and a carrier / carrier.
And a magnet 72 attached to the follower 60,
The magnet moves the stage 14 in the X direction by a small distance on a plane of motion orthogonal to the long linear motion of the stage 14 in the X direction caused by the drive assembly 22. The positions of the coil 74 and the magnet 72 can be reversed. A schematic structure of the voice coil motor (VCM) 70 is shown in FIGS. 3 and 7, and its detailed structure is as follows.
It is shown in FIG. FIG. 5 shows a sectional view of the VCM taken along the horizontal plane indicated by the arrow 5 in FIG. In FIG. 5, the magnet 72 of the VCM 70 is fixed to the carrier / follower 60 side. Also, VCM
The coil 70 includes a coil body 74A and a supporting component 7 for the coil body 74A.
4B, and the support component 74B has a connecting plate (a plate perpendicular to the XY plane) 92 that firmly extends between the two rectangular blocks 90A and 90B.
Is fixed against. The center line KX of VCM70 is
The direction of the driving force of the coil 74 is shown, and when an electric current flows through the coil body 74, the coil 74 causes a positive movement or a negative movement in the Y direction according to the direction of the electric current, and the magnitude of the electric current is shown. Generate a force corresponding to. In commonly used VCMs, a ring-shaped damper or bellows is generally provided between the coil and the magnet, thereby maintaining a gap between the coil and the magnet. The gap is maintained by the following movement of the carrier / follower 60, and
Supporting elements as described above, such as dampers or bellows, are not necessary.

In this embodiment, as shown in FIG.
Capacitive gap sensors 13A and 13A are provided as the positioning sensor 13 (see FIG. 8). In FIG. 5, rectangular blocks 90A and 90B provided with electrodes for capacitive sensors and facing each other in the X direction.
Of the gap in the X direction between the side surface of the VCM 70 and the side surface of the case 70 ′ of the VCM 70. Such a positioning sensor 13 can be placed anywhere as long as it can sense changes in the Y gap between the carrier / follower 60 and the stage 14 (or body 42). . Furthermore, sensor types are optoelectronic, dielectric,
It can be of the ultrasonic type or all non-contact type, such as air microdevices.

The case 70 'shown in FIG. 5 is integrated with the carrier / follower 60, and is provided (spatially) so as not to contact any member on the reticle stage 14 side. Case 70 'and rectangular block 90
Regarding the gap in the X direction (scanning direction) between A and 90B, when the gap on the sensor 13A side becomes large,
The gap on the sensor 13B side becomes smaller. Therefore, the gap value measured by the sensor 13A and the sensor 13
The difference between the gap value measured by B is obtained by digital or analog operation and
Controlling the drive current of the drive coil 68 for the follower 60,
The direct servo (feedback) controller is designed with a servo drive circuit that brings this gap difference to zero, which causes the carrier / follower 60 to automatically perform the following movement in the X direction. , A certain space is always maintained with respect to the stage main body 42. The indirect servo controller, which controls the flow of current to the drive coil 68 by actuation of the position controller 16 of FIG. 8, also provides a measured gap value obtained from only one of the sensors and the X-axis interference. Using the X coordinate position of the stage 14 measured from the meter, 2
It is possible to design without using the gap sensors 13A and 13B differentially.

In the VCM 70 shown in FIG. 5, the gap in the X direction (non-excitation direction) between the coil body 74A and the magnet 72 is actually about 2-3 mm. Therefore,
The following accuracy of the carrier / follower 60 with respect to the stage body 42 can be about ± 0.5-1 mm. This accuracy depends on how much the yaw rotation amount of the stage body is allowed, and also the coil body 74A of the VCM 70.
Also depends on the line length in the KX direction (excitation direction). In addition, the degree of the above-mentioned accuracy is determined by the accurate positioning accuracy of the stage main body 42 (± 0.
03 μm). This means that the servo system for the follower can be designed quite easily and the cost of equipping the follower controller is low. The line KX in FIG. 5 is set so as to pass through the center of gravity of the entire stage 14 on the XY plane, and the center of gravity of each of the pair of air bearings 66A and 66B provided inside the support bracket 62 shown in the figure. XY
It is located on the plane line KX.

In FIG. 6, the guide member 17 and the carrier /
A part including the follower 60 and the magnetic track 56A is shown in FIG.
A cross-sectional view is shown taken from the direction of arrow 6 in FIG.
The arm 24 that accommodates the magnetic track 56A includes an air bearing 32.
Is levitated and supported above the surface 12A of the base, and the carrier / follower 60 is levitated and supported above the surface 12A of the base by air bearings 66. At this time, the height of the air bearing 48 on the bottom surface of the stage body 42 (FIG. 3 or FIG. 7) and the height of the air bearing 32 are determined by the driving coil 54A on the stage body 42 side.
It is determined to maintain a 2-3 mm gap in the Z direction within the slot space of magnetic orbit 56A.

The respective Z and Y spaces between the carrier / follower 60 and the arm 24 rarely change because both the carrier / follower and the arm have a common guide. This is because it is guided by the member 17 and the surface 12A of the base. Further, on the surface 12A of the base where the air bearing 32 on the bottom of the drive frame 22 (arm 24) is guided and on the surface 12A of the base where the air bearing 48 on the bottom of the stage body is guided. Even if there is a height difference in the Z direction with the part, as long as such a difference is strictly constant within the range of the motion stroke, the Z between the magnetic track 56A and the drive coil 54A. The directional gap is also kept constant.

Furthermore, since the drive coil 68 for the carrier / follower 60 is originally fixed to the carrier / follower 60, it has a gap of 2-3 mm above and below in the slot space of the magnetic track 56A. Is designed to maintain. The drive coil 68 rarely shifts in the Y direction with respect to the magnetic orbit 56A.

Drive coils 54A, 54 on the stage 14
B, coil 74 of voice coil motor, carrier /
A cable 82 (see FIG. 2) for sending a signal is provided to the follower drive coil 68.
2 is provided on the carrier / follower 60 and the guide 17 and therefore eliminates the pulling force applied to the reticle stage 14. The voice coil motor 70 acts as a buffer by blocking transmission of mechanical disturbance force to the stage 14.

Therefore, the output of the cable will be described in detail with reference to FIGS. As shown in FIG. 2, a connector 80 for connecting the electric wire of the electric device and the pipe (hereinafter, referred to as a cable) of the pneumatic and vacuum device is provided on the base structure 12 at one end of the guide member 17. Has been. The connector 80 connects a cable 81 from an external control device (including a control device for pneumatic and vacuum devices in addition to the electrical system control device shown in FIG. 8) to a flexible cable 82. The cable 82 is also connected to the end piece 60E of the carrier / follower 60 so that the system wires and the pneumatic and vacuum tubing required for the stage body 42 are distributed as cable 83.

As mentioned above, the VCM 70 acts to eliminate the effects of cable pulling or tension, but sometimes the effects are unexpected between the carrier / follower 60 and the stage body 42. May appear as a directional moment. In other words, the cable 82
The tension of the carrier / follower 6 applies a force for rotating the guide surface of the guide member 17 or the surface 12A of the base.
0, and the tension of the cable 83 is
0 and the stage body are given a force to relatively rotate them.

One such moment, namely,
The component that shifts or moves the carrier / follower 60 is not a problem, but the stage body may be moved in the X direction and the Y direction.
The moment to shift the direction and the θ direction (yaw rotation direction) may affect the alignment or overlay accuracy. With respect to the X direction and the θ direction, the shift is performed by two linear motors (54A, 56A,
54B, 56B) can be corrected by a series of driving, and in the Y direction, the shift is VC
It can be corrected by M70. In this embodiment, the total weight of the stage 14 can be significantly reduced and the response of the VCM 70 to the movement of the stage 14 in the Y direction and the response of the linear motors in the X and θ directions is completely non-contact. Combined with the guideless structure of
Extremely high. Further, even if micron vibration (vibration in units of micron) is generated in the carrier / follower 60 and such micron vibration is transmitted to the stage 14 through the cable 83, such vibration (from several Hz to several Hz) is generated. 10 Hz
Up to) can be sufficiently solved by the high response described above.

Next, FIG. 4 shows how each cable is distributed in the carrier / follower 60. Drive coils 54A and 54B for the stage body 42
And each drive signal to the drive coil 74 of the VCM 70,
In addition, the position sensor 13 (gap sensors 13A, 13
The sensing signal from B) enters system wire 82A from connector 80. Pressure gas and vacuum to each air bearing 48, 66 enters the pneumatic system tube 82B from the connector 80. On the other hand, the drive signals to the drive coils 54A and 54B are transmitted by the electric wire 83A of the electric system connected to the stage body 42.
In addition, the pressurized gas for the air bearing 48 and the vacuum for the clamp member 42C enter the air system hose 83B.

In addition to the line shown in FIG. 2, it is preferable to provide another line for the pneumatic system for the air bearings 20, 20 'and 32 of the drive frame 22. Also, FIG.
When the tension or the vibration of the cable 83 cannot be prevented as shown in FIG. 5, it is preferable to arrange the moments due to the tension or the vibration received by the stage main body 42 so as to limit the moment to the Y direction as much as possible. In this case, the moment can be resolved only by the VCM, which has a very high response.

Referring now to FIGS. 1, 2 and 8, the positioning of the reticle stage 14 is performed using the laser interferometer device 15 by first knowing its current position. The drive signal is sent to the drive coils 54A and 54B of the reticle stage to drive the stage 14 in the X direction. When a differential force is applied to both side portions 42A and 42B of the reticle stage 14 during driving, the reticle stage 14 causes minute yaw rotation. An appropriate drive signal to the voice coil 72 of the voice coil motor 70 is
A slight displacement, that is, movement of the reticle stage 14 in the Y direction occurs. As the position of the reticle stage 14 changes, the drive signal changes to the carrier / follower coil 68.
The carrier / follower 60 follows the reticle stage 14. The resulting reaction to the applied drive forces moves the magnetic orbital assembly or drive frame 22 in a direction opposite to the movement of the reticle stage 14, thereby substantially maintaining the center of gravity of the device. It is not necessary to include a counterweight or reaction part of the magnetic track assembly 22 in the device, in which case the magnetic track assembly 22 is
It will be appreciated that it may be fixedly provided on the base 12.

As described above, the control device shown in FIG. 8 is provided to control the stage device of this embodiment. This control device of FIG. 8 will be described in detail below. Two
Drive coils 54A, 54 of the two linear motors, respectively
An X1 drive coil, an X2 drive coil configured as B, and a Y drive coil configured as the drive coil 72 of the VCM 70 are provided on the reticle stage 14, and the drive coil 68 is a carrier / slave. It is provided in the child 60. Each of these drive coils is driven by the position control device 16 according to the drive signals SX1, SX2, SY1, and SΔX. The laser interferometer device for measuring the coordinate position of the stage 14 includes an X1 axis interferometer for transmitting / receiving a beam, that is, a light beam LBY, and a beam LB.
And an X2-axis interferometer that transmits / receives X2. These interferometers provide information IFY regarding each direction of each axis,
The IFX1 and IFX2 are transmitted to the position control device 16.
The position control device 16 transmits the two drive signals SX1 and SX2 to the drive coils 54A and 54B, whereby the difference between the position information IFX1 and IFX2 in the X direction becomes the set value. That is, in other words, the yaw rotation amount of the reticle stage 14 is maintained at the set value. Therefore, needless to say during exposure, once the reticle 44 is aligned on the stage body 42, the beam LB
X1, LBX2, X1 axis interferometer and X2 axis interferometer, position control device 16, and drive signals SX1, SX2,
Positioning of yaw rotation (in the θ direction) is always performed.

Further, X-direction position information IFX1, IFX
The control device 16 which has obtained the current coordinate position of the stage 14 in the X direction from the average value of the sum of the two is various commands from the host CPU 16 ′ and information C regarding each parameter.
Drive signals SX1 and SX2 based on D
4A and 54B, respectively. In particular, when scanning exposure is operating, it is necessary to move the stage 14 linearly in the X direction while correcting the yaw rotation amount, and the control device 16 applies the same or slightly different force as necessary. While controlling the two drive coils 54A and 54B.

The position information IFY from the Y-axis interferometer
Is also sent to the control device 16, which sends the optimum drive signal SΔX to the drive coil 68 of the carrier / follower 60. At this point, controller 16
The sensing signal Spd from the position sensor 13 which measures the space in the X direction between the reticle stage 14 and the carrier / follower 60 is received, and the necessary signal SΔX is transmitted to bring the signal Spd to the above-mentioned set value. . The tracking accuracy of the carrier / follower 60 is not so strict, and the sensing signal Spd of the control device 16 does not need to be strict. For example, position information IFY, IFX1 from each interferometer every 1 millisecond,
When controlling the motion by reading IF2, the high speed processor (arithmetic device) of the controller 16 samples the current of the sensing signal Spd each time, and the value is
It is determined whether it is larger or smaller than the reference value. If the deviation exceeds a certain point, a signal SΔX proportional to the deviation can be transmitted to the drive coil 68. Further, as described above, the drive coil 68 is directly servo-controlled, and the follow-up movement of the carrier / follower 60 is directly controlled without passing through the position control device 16.
A controller 95 can also be provided.

Since the movable stage device shown in the drawing has no attachment for restraining the movable stage device in the X direction, a small influence causes such a stage device to drift in the positive X direction or the negative X direction. That is, it may be changed. This can cause certain components to collide with each other when such imbalance becomes excessive. The effects include cable forces, inaccurate leveling or leveling of the base reference surface 12A, or friction between components. One simple method is to use a weak bumper (not shown) to prevent excessive movement of drive assembly 22. Another simple method is to shut off the supply of air to one or more air bearings (32, 20) used to guide the drive assembly 22 when the drive assembly reaches near the end of the stroke. It is to be. Such air bearings
It can be activated when the drive back in the opposite direction begins.

A more accurate method is a measuring means (not shown).
Requires monitoring the position of the drive assembly and providing the driving force to restore and maintain the correct position. The accuracy of such measuring means does not have to be strict, but accuracy of the order of 0.1 to 1.0 mm is required. The driving force may be provided by another linear motor (not shown) attached to the drive assembly 22 or another motor connected to the drive assembly.

Finally, deactivate the one or more air bearings (66, 66A, 66B) of the carrier / follower 60 to act as a brake during the idle period of stage 42. You can When the coil 68 of the carrier / follower 60 is excited, the carrier / follower 60 is
When is under braking, the drive assembly is driven and accelerated. Therefore, the position control device 1
6 monitors the position of the drive assembly 22. As the drive assembly drifts out of position, the drive assembly is repositioned with sufficient accuracy using the coil 68 of the carrier / follower 60 intermittently.

In the first embodiment of the present invention, the drive frame 22 functioning as a counterweight is provided so as not to move the center of gravity of the entire apparatus,
The stage body 42 is moved in the opposite direction. However, when the structure of FIGS. 1 to 7 is applied to a device in which the movement or shift of the center of gravity is not a big problem,
The drive frame 22 can also be fixed together with the base structure 12. In such a case, some effects and functions can be obtained without making any changes to the device, except for the problem of the center of gravity.

The present invention provides a stage that can be used to provide highly precise position and motion control with three degrees of freedom in a plane. Its features are (1) long linear motion, (2) short linear motion orthogonal to such long linear motion, and (3) small yaw rotation amount. By using electromagnetic force as a stage driver (stage driving device), this stage is insulated from the mechanical adverse effects of the surrounding structure. A high control bandwidth can be obtained by using the structure for the guideless stage. These two
Three points contribute to achieving smooth and accurate operation of the stage.

Description of the Preferred Embodiment With the description of the embodiment shown in FIGS. 1-8 in mind, FIG.
10 and FIG. 10, there is shown a preferred embodiment of the present invention, in which the reference numeral 2 below each reference numeral of each component of this embodiment.
The digits generally correspond to the two-digit reference numbers for each of the components in FIGS.

In FIGS. 9 and 10, unlike the first embodiment described above, the drive frame functioning as a counterweight has been removed and the magnetic tracks 156A, 156B of each of the two linear motors have a base structure 112. It is firmly attached to. The stage body 142 that moves linearly in the X direction has two magnetic tracks 156A and 156B.
It is provided between. As shown in FIG. 10, an opening 112B is formed in the base structure 112, and the stage body 142 is arranged so as to straddle the opening portion 112B in the Y direction. Four preload type air bearings 148 are fixed to the bottom surface at both ends of the stage body 142 in the Y direction.
Are levitated and supported against the surface 112A of the base.

Further, according to the present embodiment, the reticle 14
4 are sandwiched and supported on a reticle holding plate, that is, a reticle chuck plate 143, which is separately provided on the stage main body 142. Linear mirror 150Y for Y-axis laser interferometer and two corner mirrors 150X1, 15 for X-axis laser interferometer
0X2 is provided on the reticle chuck plate 143. The drive coils 154A and 154B have magnetic tracks 156 at both ends of the stage body 142 in the Y direction.
The stage main body 142 is linearly moved in the X direction by the control subsystem described above, and is yawed by an extremely small amount.

As is apparent from FIG. 10, the right magnetic orbit 156B of the linear motor and the left magnetic orbit 156A of the linear motor are arranged so that the heights in the Z direction between these orbits are different. . In other words, the bottom surfaces of both ends of the left-side magnetic orbit 156 in the direction of the long axis are arranged at a certain height above the surface 112A of the base using the block member 155, as shown in FIG. ing. Carrier / follower 1 with VCM fixed
60 is provided in the space below the upper magnetic orbit 156A.

The carrier / follower 160 is levitated and supported by preloaded air bearings 166 (two points) on the surface 112A 'of the base of the base structure 112 at a lower height. In addition, the vertical guide surface 11 of the linear guide member 117 provided on the base structure 112.
Two preloaded air bearings 164 facing 7A are fixed to the sides of the carrier / follower 160. This carrier / follower 160 differs from that shown in FIG. 4 for the above-described embodiment, in that the drive coil 168 (FIG. 9) for the carrier / follower 160 extends vertically from the bottom of the carrier / follower 160. Fixed horizontally against the elongating parts,
In addition, it is provided in the magnetic flux slot of the magnetic track 156A without contact. The carrier / follower 160
The VCM 170 is provided so as not to come into contact with any part of the magnetic track 156A within the range of the motion stroke, and accurately positions the stage body 142 in the Y direction.

Further, in FIG. 9, the air bearing 166 for levitating and supporting the carrier / follower 160 is a VCM.
It is provided below 170. Carrier / Follower 160
The following movement of the stage body 142 is also performed based on the sensing signal from the position sensor 13 as in the above-described embodiment.

In the second embodiment constructed as described above, since there is substantially no member that functions as a counterweight, the center of gravity of the entire apparatus is the stage body 1.
There is an inconvenience of moving or shifting in accordance with the shift of 42 in the X direction. However, using the carrier / follower 160, the stage body 14
By following 2, it is possible to accurately position the stage body 142 in the Y direction by the non-contact electromagnetic force of the VCM 170. Further, since the two linear motors are arranged so that there is a difference in the height direction Z, the vector sum of the force moments generated by the respective linear motors is made extremely small at the center of gravity of the entire reticle stage. This is possible because the force moments of the respective linear motors substantially cancel each other out.

Further, the action axis of the VCM 170 in the longitudinal direction (line KX in FIG. 5) passes through the center of gravity of the entire stage structure not only on the XY plane but also in the Z direction.
It becomes more difficult for the driving force of the CM 170 to give an unnecessary moment to the stage main body 142. In addition, the method of connecting the cables 82 and 83 via the carrier / follower 160 can be applied in the same manner as in the first embodiment described above, so that there is also a problem with a completely non-contact type guideless stage. Be improved.

The same guideless principle can be adopted in other embodiments. For example, in FIGS. 11 and 12, the stage 242 supported on the base 212.
Is driven in the longitudinal X direction by a single moving coil 254 that moves in a single magnetic orbit 256. The magnetic track is rigidly attached to the base 212. The center of gravity of the coil is located near the center of gravity of the stage 242. To move the stage in the Y direction, a pair of V
The CM (274A, 274B, 272A, 272B) is activated to give an acceleration force in the Y direction. To control yaw rotation or yawing, coils 274A, 274B are used.
Are activated differentially under the control of the electronic subsystem. VCM magnets (272A, 272B) are mounted on the carrier / follower stage 260. The carrier / follower stage is guided and driven as in the first embodiment described above. This alternative embodiment can be used for wafer stages. When used in a reticle stage, coil 254 and track 256
A reticle can be provided on one side of the stage 242, and if the center of gravity of the stage 242 needs to be maintained through the coil 254 and the trajectory 256, the stage 242 can be provided with a compensating aperture to keep it balanced. It can be provided on the side of the coil 254 and the track 256 opposite to.

The advantages obtained from each of the above embodiments can be roughly summarized as follows. To maintain accuracy, the carrier / follower design eliminates cable tension problems for the stage as the cable connected to the stage follows the stage through the carrier / follower. The cable connecting the carrier / follower to the external device has a certain amount of tension, but the stage is not so affected, because
By blocking the transmission of mechanical disturbances to the stage, the stage is not directly connected to the carrier / follower acting as a buffer.

Also, due to the design of the counterweight,
Using the law of conservation of momentum, the position of the center of gravity of the stage device is maintained during movement of the stage in the long stroke direction. This device substantially eliminates the reaction forces between the stage device and the base structure to which the stage device is mounted, thereby allowing high accelerations while minimizing the effect of vibrations on the device.

Also, since the stage is designed to perform a limited motion in three degrees of freedom, as described above, such a stage has a full range of motion in all three degrees of freedom. Extremely simple compared to stages designed to exercise. Also, unlike non-commutator type devices, the present invention uses commercially available electromagnetic elements. Since the present invention does not require a bespoke electromagnetic element that becomes increasingly difficult to manufacture as the size and stroke of the stage increase, the present invention facilitates changing the size or stroke of the stage. Is.

In the embodiment using a single linear motor, it is not necessary to use the other linear motor, and the yaw angle can be corrected by using two VCMs. Although the invention has been described with reference to the preferred embodiments, the invention can take various other forms and be limited only by the claims.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of the device of the present invention.

FIG. 2 is a plan view of the device shown in FIG.

3 is an elevational view of the structure shown in FIG. 2 as viewed in the direction of the arrow along line 3-3.

FIG. 4 is an enlarged perspective view showing the partially exploded carrier / follower structure of FIG. 1 from a positioning guide.

5 is an enlarged horizontal sectional view showing a part of the structure shown in FIG. 7 as viewed in the direction of the arrow along the line 5. FIG.

FIG. 6 is an enlarged vertical sectional view showing a part of the structure shown in FIG. 2 with the voice coil motor removed, as seen in the direction of the arrow along the line 6;

7 is a portion of the structure shown in FIG. 2 taken along line 7-7
It is a vertical sectional view shown and seen in the direction of an arrow.

FIG. 8 is a block diagram schematically showing a sensing / control device for controlling the position of the stage.

FIG. 9 is a plan view similar to FIG. 2, showing a preferred embodiment of the present invention.

10 shows the structure shown in FIG. 9 along line 10-10
It is a vertical sectional view shown and seen in the direction of an arrow.

FIG. 11 is a plan view similar to FIG. 9, showing another embodiment of the present invention in a greatly simplified manner.

FIG. 12 is an elevational view similar to FIG. 10, showing a further embodiment of the invention in a highly simplified manner.

[Explanation of symbols]

10 Positioning device 12 base structure 14 reticle stage 16 Position control device 16 'CPU 17A, 17B guide surface 17 Positioning guide 18 Support bracket 20 air bearing 22 Drive assembly (drive frame) 24, 26 Magnetic orbital arm 32 air bearing 42 Main body 52 Electromagnetic drive assembly 54A, 54B drive coil 56A, 56B magnetic orbit 60 carriers / followers

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5F046 BA05 CB17 CC02 CC16 CC17                       CC20

Claims (26)

[Claims] 1. A counterweight carrying one member of each linear motor is suspended on a base structure, and when the acting force for moving the stage in the first direction is applied on the base structure, the counterweight performs the action. The stage is a reticle stage of an exposure apparatus that maintains the center of gravity by moving in the opposite direction according to a force and exposes the pattern of the reticle onto a substrate, and is provided below the reticle stage and the counterweight. An exposure apparatus comprising a projection optical device for projecting the pattern of 1. above onto the substrate. 2. An exposure apparatus comprising a reticle stage that moves linearly in at least a first direction on a reference plane, and exposing a reticle pattern held by the reticle stage onto a substrate, wherein: (a) the reticle Adjacent to the side of the stage,
A counterweight movable in the first direction, and (b) a first magnetizing member provided on the reticle stage so as to generate a driving force in the first direction, and the counterweight provided on the counterweight. A second magnetizing member, and driving means for electromagnetically driving the reticle stage; (c) the reticle stage and the counterweight, provided below the reticle stage and projecting the reticle pattern onto the substrate. An exposure apparatus comprising: a projection optical device, wherein the reticle stage and the counterweight move in opposite directions in the first direction above the projection optical device by excitation of the driving means. . 3. The exposure apparatus according to claim 2, wherein the reference surface is formed on a base structure provided above the projection optical apparatus. 4. The exposure apparatus according to claim 2, wherein the reticle stage moves on the reference surface via a first fluid bearing, and the counterweight is located at a position different from that of the first fluid bearing. An exposure apparatus which moves via a second fluid bearing provided. 5. The exposure apparatus according to claim 2, wherein the counterweight moves on the reference surface. 6. The exposure apparatus according to claim 2, wherein one of the first magnetizing member and the second magnetizing member is a coil, and the first magnetizing member and the second magnetizing member. An exposure apparatus characterized in that the other of the members is a magnet. 7. The exposure apparatus according to claim 1, further comprising a laser interferometer device that detects a position of the reticle stage. 8. The exposure apparatus according to claim 1, wherein the driving unit corrects yawing of the reticle stage. 9. The exposure apparatus according to claim 2, wherein the drive unit has a pair of drive assemblies. 10. The exposure apparatus according to claim 1, wherein the counterweight has an arm extending in the first direction. 11. The exposure apparatus according to claim 1, wherein the counterweight has a rectangular shape. 12. The exposure apparatus according to claim 1, further comprising a linear motor that adjusts a position of the counterweight. 13. The exposure apparatus according to claim 1, wherein the exposure apparatus exposes a pattern of the reticle onto the substrate while the reticle stage is being scanned. An exposure apparatus, which is an exposure apparatus. 14. An exposure method, comprising: a reticle stage that linearly moves in at least a first direction on a reference plane, and exposing a reticle pattern held by the reticle stage onto a substrate. A first magnetizing member and a second magnetizing member provided, and the reticle stage includes the first magnetizing member and the first magnetizing member.
A drive means for moving in a direction, and a step of moving the reticle stage and a counterweight provided with the second magnetizing member in opposite directions in the first direction by excitation of the drive means, And a step of projecting the pattern of the reticle onto the substrate by a projection optical device provided below the reticle stage and the counterweight. 15. The exposure method according to claim 14, wherein the reference surface is formed on a base structure provided above the projection optical device. 16. The exposure method according to claim 14, wherein the step of moving the reticle stage on the reference surface via a first fluid bearing is different from the step of moving the counterweight to the first fluid bearing. An exposure method comprising a step of moving through a second fluid bearing provided at a position. 17. The exposure method according to claim 14, wherein the counterweight moves on the reference surface. 18. The exposure method according to claim 14, wherein one of the first magnetizing member and the second magnetizing member is a coil, and the first magnetizing member and the second magnetizing member are coils. An exposure method, wherein the other of the members is a magnet. 19. The exposure method according to claim 14, further comprising a step of detecting a position of the reticle stage by a laser interferometer device. 20. The exposure method according to claim 14, further comprising a step of correcting yawing of the reticle stage by the driving unit. 21. The exposure method according to claim 14, wherein the drive unit has a pair of drive assemblies. 22. The exposure method according to claim 14, wherein the counterweight has an arm extending in the first direction. 23. The exposure method according to claim 14, wherein the counterweight has a rectangular shape. 24. The exposure method according to claim 14, further comprising the step of adjusting the position of the counterweight by a linear motor. 25. The exposure method according to claim 14, wherein the reticle pattern is exposed on the substrate while the reticle stage is being scanned. Exposure method. 26. The exposure apparatus according to claim 1, wherein the reticle stage is a guideless stage.