JPH11142556A - Controlling method for stage, stage device and exposing device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stage controlling-method capable of raising moving velocity in all direction at the time when moving a table put by a positioning object in two directions on a two-dimensional plane. SOLUTION: On a surface plate 3, an XY moving stage 14, movers 17A, 17B and 32 and a movable table 45 consisting of a Z-leveling stage 20, a sample stage 22, etc., are put. The movable table 45 is relatively driven against a carrier consisting of a stator carrier 8A, (8B) and stators 16A, 16B and 33 in Y- direction with Y-axis motors 18A and 18B and in X-direction with an X-axis motor 31. For widening the stroke in X-direction, the carrier and the movable table 45 are integrally driven in X-direction with stable carrier driving motors 10A and 10B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage control method and a stage apparatus for precisely positioning a workpiece, for example, a lithography process for manufacturing a semiconductor element, a liquid crystal display element, a thin film magnetic head, and the like. It is suitable for use in an exposure apparatus used for transferring a mask pattern onto a substrate such as a wafer, or a precision machine tool or a precision measuring instrument.

[0002]

2. Description of the Related Art For example, when a semiconductor device or the like is manufactured, a pattern of a reticle as a mask is transferred onto a wafer (or a glass plate or the like) coated with a resist as a photosensitive substrate. An exposure type projection exposure apparatus (stepper) has been used. In such a batch exposure type exposure apparatus, a wafer stage capable of stepping in two orthogonal directions is used as an apparatus for moving each shot area of a wafer to a predetermined exposure position. Since the exposure apparatus is required to improve not only the positioning accuracy but also the throughput (productivity), the table section on which the wafer in the wafer stage is mounted and moved is made as light as possible, and the friction with the guide surface is reduced. It is required to reduce the size of the table so that the table can be moved with high accuracy and at high speed.

As a stage device usable for such a wafer stage, for example, Japanese Patent Laid-Open Publication No. 3-142136 discloses a table on which a wafer or the like is slidably mounted on a predetermined base via an air bearing. A stage device that disposes the table two-dimensionally via a carriage connected to the table by Lorentz force is disclosed.

[0004]

In the conventional stage apparatus as described above, since the table is held in a substantially non-contact manner on a horizontal plane, the friction with the guide surface is reduced, and the table is moved by its carriage. The table can be moved with high accuracy and high speed in a direction in which the table can be relatively moved with respect to the table. However, in the conventional stage device, it is necessary to always move the table and the carriage integrally in the direction in which the table is restrained with respect to the carriage (a minute movement is possible). There was a disadvantage that the speed could not be increased so much. Therefore, when the stage apparatus is used for a wafer stage of a batch exposure type exposure apparatus, the stepping speed in one of two orthogonal directions becomes slow, and the throughput of the exposure step cannot be increased much. Become.

In recent years, as an exposure apparatus, a scanning exposure type projection exposure apparatus (scanning exposure apparatus) such as a step-and-scan method for performing exposure by synchronously scanning a reticle and a wafer with respect to a projection optical system. ) Is also attracting attention. In such a scanning type exposure apparatus, together with a wafer stage that performs stepping in two orthogonal directions and continuously moves at a constant speed in the scanning direction, it can continuously move at a constant speed in the scanning direction and has a very small amount in the non-scanning direction. A movable reticle stage is used. However, since the conventional stage device was not developed especially for the scanning type exposure apparatus, it was difficult to increase the throughput of the exposure process using the scanning type exposure apparatus.

In view of the above, the present invention provides a stage control method capable of increasing a moving speed in any direction when a table on which a positioning target is placed is moved in two directions on a two-dimensional plane. A first object is to provide a stage device that can use this control method. It is a second object of the present invention to provide a stage control method capable of increasing the throughput of an exposure step particularly when used in a scanning type exposure apparatus, and a stage apparatus which can use this control method.

It is a third object of the present invention to provide an exposure apparatus having such a stage apparatus and obtaining a high throughput.

[0008]

A first stage control method according to the present invention is directed to a stage control method for moving a table (22 or 45) on which a positioning object (W) is mounted on a two-dimensional plane. A carrier (8A, 8B, 16A, 16B, 33) for holding the table and moving the table two-dimensionally within a predetermined movement range;
When the table is moved to a wider range than the moving range, the carrier is moved in a predetermined one-dimensional direction (X direction) on the two-dimensional plane.

According to the present invention, the table (22)
Is driven by the carrier in a guideless manner in, for example, orthogonal X and Y directions. At this time, the table (22) is moved in a predetermined direction (for example, Y
Direction), it is possible to drive with a wide stroke. However, simply driving with a wide stroke in the X direction orthogonal thereto also requires a movement of the drive mechanism in the Y direction, which increases the load. Therefore, the carrier is provided with only a mechanism for driving with a narrow stroke in the X direction, and the table (22) can be driven at a high speed with a light load in the X direction within the stroke.

When the table (22) is driven with a wide stroke in the X direction, the table (22) is driven integrally with the carrier. As described above, the load at the time of driving as one unit increases, but when the present invention is applied to, for example, a wafer stage of an exposure apparatus, a step-and-repeat method or a step
In any of the AND scan methods, it is only necessary to be able to move by a width of one shot area in the X direction and the Y direction.
Direction, and the table (22) is relatively moved in the −X direction within the carrier, and the table (22) is moved only within the carrier when moving between shots.
Is stepped in the X direction, the load of the movement in the X direction is substantially reduced.

In particular, when the present invention is applied to a scanning type exposure apparatus, the moving direction (scanning direction) of the wafer during scanning exposure
Is set to the direction in which a wide stroke can be obtained by the carrier (Y direction), and the non-scanning direction is set to the direction of a narrow stroke (X direction). By gradually moving the carrier in the X direction during the scanning exposure, the table (22) can be moved at high speed within the carrier between shots, and the throughput is improved.

Further, the stage device according to the present invention provides a table (22 or 4) on which a positioning object (W) is placed.
In the stage device for moving 5) on a two-dimensional plane, a carrier (8A, 8B, 16A, 16B, 33) that holds the table by electromagnetic force and moves the table two-dimensionally within a predetermined moving range. ) And driving means (10A, 10B) for moving the carrier in a predetermined one-dimensional direction (X direction) on the two-dimensional plane. With such a stage device, the stage control method of the present invention can be used.

In this case, as an example, the carrier is mounted on a predetermined base (3) that defines the two-dimensional plane, and the table (22) is mounted on the base via a hydrostatic gas bearing. . Thereby, the table (2)
The sliding resistance of 2) becomes extremely small, so that higher-precision and higher-speed movement becomes possible. Next, the first method according to the present invention is described.
The exposure apparatus includes a table (22) on which a substrate (W) as an object to be positioned is placed and movably supported on a two-dimensional plane, and the substrate is moved through the two-dimensional plane via the table. By moving the mask (R) in the corresponding direction in synchronization with the movement in the first direction (Y direction) above, the pattern of the mask is moved to the first shot area (25A) on the substrate. After the scanning exposure, the table (22) is step-moved in at least one of a second direction (X direction) crossing the first direction on the two-dimensional plane and the first direction, and In an exposure apparatus for starting scanning exposure on a second shot area (25B) on a substrate, a table (22) is held by electromagnetic force, and the table is moved in the first direction in an exposure range on the substrate. Range over Moved in the inner and the second is the direction the carrier (8A moving the center distance or more in the range of the shot areas adjacent on the substrate (DX), 8B, 1
6A, 16B, 33) and this carrier in a table (2
2) driving means (10A, 10B) for moving in the second direction within a range covering the exposure range on the substrate;
Control means (52) for the carrier and its driving means;
Having.

Further, in the exposure apparatus, the second shot area (25B) is used for the first shot area (2B).
5A), when located in a row adjacent in the second direction to the first shot area (25A) on the substrate, the control means moves the substrate through the carrier during scanning exposure to the first shot area (25A). In parallel with the movement in the first direction, the carrier is moved in the second direction through the driving means, and after the exposure to the first shot area (25A) is completed, the table is moved through the carrier. (22) is step-moved at least in the second direction.

According to the exposure apparatus of the present invention, during scanning exposure, the carrier as a whole is used in order to keep the position of the table (substrate) in the second direction (X direction) constant. In synchronization with the continuous movement in the X direction by the driving means, the table in the carrier is -X
Move continuously in the direction. When the next shot area is moved to the scanning start position, the table is relatively moved only within the carrier without using the driving means. As a result, the table is moved at high speed between shots in any direction.

Next, a second exposure apparatus of the present invention is an exposure apparatus for exposing a pattern of a mask onto a substrate, which is supported from the floor surface via vibration isolating means (2A to 2C) and the substrate (W) And a carrier (8A, 8B, 16A, 16B, 33) for moving the table in a two-dimensional plane, and a body provided separately from the main body. Driving means (10A, 10B) for moving the carrier in a one-dimensional direction in the two-dimensional plane
And According to such an exposure apparatus, a high throughput can be obtained because the exposure apparatus includes the stage apparatus of the present invention.

Next, according to a second stage control method of the present invention, a table (22 or 4) on which a positioning object is placed is placed.
5) In the stage control method for moving the table on a two-dimensional plane, the position of the table in the first direction and the position of the table in the second direction orthogonal to the first direction are measured, and the table is moved on the two-dimensional plane. Carrier (8A, 8
B, 16A, 16B, 33) in the first direction to measure the position of the table. According to such a stage control method, the first
And the table can be moved at high speed in the second direction.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In this embodiment, the present invention is applied to a wafer stage of a projection exposure apparatus of a step-and-scan method for manufacturing a semiconductor device. FIG.
2 shows a schematic configuration of the projection exposure apparatus of the present example, and FIG. 2 shows a configuration of the projection exposure apparatus on the wafer stage side.
First, in FIG. 1, four anti-vibration tables 2A to 2D are provided on the floor.
(2C and 2D are not shown in the drawing), a rectangular flat platen 3 is supported. Anti-vibration table 2A, 2B
Each of them comprises an air spring (or a coil spring) having a large elasticity and an oil damper as a vibration damper. The surface of the surface plate 3 is a plane having an extremely good flatness, and the surface is held substantially parallel to the horizontal plane when the projection exposure apparatus is not operating. The description will be made by taking the X axis in parallel, the Y axis perpendicular to the plane of FIG. 1, and the Z axis in a direction perpendicular to the surface of the surface plate 3.

As shown in FIG. 2, in this example, the surface plate 3 is Y
A pair of stator carrier guides 4A and 4B are arranged parallel to the X axis so as to be sandwiched in the direction, and the guide 4A is installed on the floor via the stator carrier support bases 5A and 6A, and the other guide 4B. Are symmetrically placed on the floor via the stator carrier support 6B and the like. Guides 4A, 4B
The sliders 7A and 7B for the stator carrier are slidably mounted in the X direction via static pressure air bearings, and the flat stator carriers 8A and 8B are fixed on the sliders 7A and 7B, respectively. I have. A fixed carrier drive motor 10A composed of a linear motor includes a stator 12A long in the X direction fixed on the protrusions of the stator carrier support bases 5A and 6A and a mover 11A fixed to the stator carrier 8A. Is configured. The stator 12A has a pair of permanent magnets 26 inside a yoke having a U-shaped cross section.
Are arranged in the X-direction while sequentially reversing the polarity, and the mover 11A includes coils of a plurality of phases.

On the other stator carrier 8B side, the stator 12 fixed on a convex portion such as the stator carrier support 6B is also provided.
B and a fixed carrier driving motor 10B composed of a linear motor composed of a mover 11B fixed to the stator carrier 8B. The stator carriers 8A and 8B are guided by fixed carrier driving motors 10A and 10B.
It is driven in the X direction along A and 4B over the entire movement range (full stroke) on the surface plate 3. An X-axis movable mirror 28 is fixed on the stator carrier 8B. And column 3
4 (see FIG. 1), a laser beam is emitted in parallel to the X-axis from an X-axis laser interferometer 29X attached to a part of
The X coordinate of the stator carrier 8 is measured by the laser interferometer 29X.

The stators 16A and 16B and the stator 33 are connected in parallel to the Y axis so as to connect the stator carriers 8A and 8B and to straddle the platen 3 in the Y direction.
Is fixed (erected). The stator 33 is fixed at an intermediate position between the stators 16A and 16B in the X direction. Each of the stators 16A and 16B is configured by arranging a large number of magnets identical to the pair of permanent magnets 27 in the Y direction while sequentially reversing the polarities inside a yoke having a U-shaped cross section. The stators 16A and 16B are symmetrically arranged so that the openings face each other. The detailed configuration of the stator 33 will be described later. Further, the platen 3 is provided on the bottom side of the stator 33.
XY moving table 14 on the upper surface of the XY moving table via a static pressure air bearing
Are mounted, and support plates 15A and 15B are implanted on the XY moving table 14 so as to sandwich the stator 33 in the X direction.
A Z leveling stage 20 is fixed on the upper surfaces of 5A and 15B, a rectangular plate-shaped sample stage 22 as a table is fixed on the Z leveling stage 20, and a wafer W is vacuum-adsorbed on the sample stage 22 via a wafer holder 23. Is held by The distance between the support plates 15A and 15B in the X direction is set to be wider than the width of the stator 33 in the X direction by the width DX or more, and the XY moving table 14 and the sample table 22 (and thus the wafer W) are fixed to the platen 3 in the Y direction. The upper full stroke is configured to be movable in the X direction relative to the stator 33 and the stator carriers 8A and 8B at least within a range of the width DX without a guide.

In this case, on the bottom surface of the XY moving table 14, there are provided air ejection portions constituting a static pressure air bearing, and near these air ejection portions, a preload mechanism such as a magnet or a vacuum pocket is incorporated. XY mobile platform 1
4 moves the upper surface of the platen 3 with a very low frictional force in a non-contact manner with a predetermined gap. Further, the sample stage 22 can correct the position (focus position) in the Z direction and the tilt angle around the X axis and the Y axis by the Z leveling stage 20, and the end of the sample stage 22 in the −X direction. , And + Y
An X-axis movable mirror 19X and a Y-axis movable mirror 19Y are fixed to the ends in the directions. Then, a two-axis X attached to a part of the column 34 (see FIG. 1) on the surface plate 3
Axis laser interferometers 21XA and 21XB to moving mirror 19
X is irradiated with a laser beam in parallel with the X axis, and the X-coordinates XW1 and XW2 of the movable mirror 19X (sample stage 22) are measured by the laser interferometers 21XA and 21XB. For example, one X coordinate XW1 becomes the X coordinate of the sample stage 22, and 2
The rotation angle of the sample stage 22 is calculated from the difference between the two X coordinates XW1 and XW2. Further, the Y-axis laser interferometer 2 attached to another position of the column 34 (see FIG. 1) on the surface plate 3
The laser beam from 1Y is irradiated on the movable mirror 19Y on the sample stage 22 in parallel with the Y axis, and the Y coordinate YW of the movable mirror 19Y (sample stage 22) is measured by the laser interferometer 21Y.

Returning to FIG. 1, a pair of Y-axis motors 18A and 18B composed of linear motors are constituted by movers 17A and 17B fixed outside the support plates 15A and 15B and corresponding stators 16A and 16B. Have been. Mover 17
A and 17B each have a multi-phase coil.
The sample table 22 and the like are driven in the Y direction along the stators 16A and 16B in a non-contact manner by the shaft motors 18A and 18B, and are rotated within a predetermined range. Further, an X-axis motor 31 is constituted by the mover 32 fixed inside the support plate 15B in the −X direction and the corresponding stator 33, and the X-axis motor 31 is configured to move in the X direction by Lorentz force generated by the X-axis motor 31. By the thrust FX, the sample stage 22 and the like are driven within a predetermined range in the X direction relative to the stator 33 (stator carriers 8A and 8B). Further, the sample table 22 is provided on the upper surface of the platen 3.
A rectangular parallelepiped frame-shaped column 34 is planted so as to surround the like.

Here, the configuration of the X-axis motor 31 is shown in FIG.
This will be described with reference to FIG. FIG. 5A shows the mover 32 of FIG.
5 (b) is a side view of FIG. 5 (a), showing the X-axis motor 31 including the stator 33 and the stator 33, and FIG. A permanent magnet 39 is provided on one inner surface of one of the three yokes 40, 38A, 38B fixed in a U-shape so that the polarity is reversed in the X direction.
A, 39B are fixed, and permanent magnets 39A, 3
The permanent magnet 39C with the polarity attracting to face 9B,
39D is formed to be fixed. Therefore, the direction of the magnetic flux generated between one pair of permanent magnets 39A and 39C is:
The direction of the magnetic flux generated between the other pair of permanent magnets 39B and 39D is opposite, and the mover 32 is inserted in a non-contact manner between these two pairs of permanent magnets.

As shown in FIG. 5A, inside the mover 32, a coil 32a is wound a plurality of times in a rectangular shape. In this case, the current IX flowing through the coil 32a is opposite to each other in the + Y direction or the −Y direction between one pair of permanent magnets 39A and 39C and between another pair of permanent magnets 39B and 39D. It is assumed that the thrust DX / Lorentz force is applied to the mover 32 in the X direction between the permanent magnets 39A and 39C.
When 2 acts, a thrust DX / 2 composed of Lorentz force acts on the mover 32 in the X direction even between the permanent magnets 39B and 39D. Since the Lorentz force is proportional to the current IX, the total thrust direction of DX is controlled by controlling the current IX.
And the size can be arbitrarily controlled.

At this time, even if the position of the mover 32 in the X direction changes within a certain range, as long as the coil 32a of the mover 32 is located between the corresponding permanent magnets of the stator 33, the mover 32 32, the proportionality coefficient (thrust constant) between the generated current IX and the generated Lorentz force is substantially constant.
2 can always be given a desired thrust FX in the X direction. Therefore, the X-axis motor 31 including the mover 32 and the stator 33
Thereby, the sample stage 22 and the like in FIG. 1 can be driven in the X direction within a predetermined range.

In the X-axis motor 31 shown in FIG. 5, the permanent magnet and the coil may be reversed as shown in FIG. That is, FIG. 6A is a plan view showing another configuration example of the X-axis motor 31, and FIG. 6B is a side view thereof. As shown in FIG. The permanent magnets 42A, 32A are provided on one inner surface of one of three yokes 40A, 41A, 41B fixed in a U-shape so that the polarity is reversed in the X direction.
42B is fixed, and the permanent magnets 42A and 42B
The permanent magnets 42C and 42 have polarities that attract each other so that they face each other.
D is fixed. A stator 33A long in the Y direction is inserted between the two pairs of permanent magnets in a non-contact manner so as to cover the entire moving range of the mover 32A.

As shown in FIG. 6A, a coil 33Aa is wound a plurality of times in a rectangular shape inside the stator 33A. Therefore, also in this modified example, when the coil 33Aa is energized, the stator 33 is moved between the permanent magnets 42A and 42C.
Lorentz force generated in A and permanent magnets 42B, 42D
And the Lorentz force generated in the stator 33A is in the same direction, and the reaction force of the total Lorentz force acts as a thrust on the mover 32A.

Next, the configuration and operation of the wafer stage of this embodiment will be described in detail. First, FIG. 3 shows a state in which the Z leveling stage 20 is mounted on the wafer stage shown in FIG. 2. In FIG. 3, the Z leveling stage 20 has support plates 15A and 15B fixed on the XY moving table 14. Is fixed to a screw hole on the upper surface by a bolt (not shown). Then, the XY moving table 14, the support plate 15
A, 15B, movers 17A, 17B, 32, Z leveling stage 20, sample stage 22, wafer holder 23, and movable mirrors 19X, 19Y constitute movable table 45 integrally. Further, the stators 16A, 16B, 33 and the stator carriers 8A, 8B correspond to the carrier of the present invention.

FIG. 4 is a plan view showing the relationship between the carrier and the movable table 45 (typically, the Z leveling stage 20 is indicated by a dotted line). As shown in FIG. The carriers (stator carriers 8A, 8B and stators 16A, 16B, 33) are driven in a full-stroke non-contact manner in the Y direction via Y-axis motors 18A, 18B.
1 is driven in a non-contact manner in the X direction within a range of a predetermined width DX. The range of the width DX is represented as a moving range of the center 20a of the Z leveling stage 20 in the X direction. The width DX is, for example, 1 to 2 times the maximum value of the arrangement pitch in the X direction of the shot area on the wafer to be exposed.
It is set to about twice (in this example, about 1.5 times). Assuming that the maximum value of the arrangement pitch in the X direction is 30 mm, the width DX is about 30 to 60 mm (45 mm in this example).
Degree).

As described above, the movable table 45 of this embodiment is restrained by its electromagnetic force only with respect to its carrier. Actually, even if the movable table 45 moves in the X direction within a range slightly exceeding the width DX,
A, 17B and 32 are stators 16A, 16B and 3 respectively.
Since there is a margin so that the movable table 45 does not contact the movable table 45, the movable table 45 can be rotated. That is, the thrust FY in the + Y direction is applied to the movable table 45 by the one Y-axis motor 18A, and the other Y-axis motor 18A.
By applying the thrust FY in the −Y direction to the movable table 45 by B, the movable table 45 (and thus the wafer W) can be rotated by a desired angle around an axis parallel to the Z axis (θ direction).

Returning to FIG. 3, in this example, the carriers (stator carriers 8A and 8B and stators 16A and 16A)
B, 33) are driven by the fixed carrier drive motors 10A, 10B in a full stroke in the X direction integrally with the movable table 45. FIG. 7 shows a state in which only the movable table 45 is disassembled and placed on the surface plate 3. In FIG. 7, flexible air pipes 43 are provided in many air ejection holes on the bottom surface of the XY moving table 14. Through the external air pump 44
A more predetermined pressure is supplied, and the movable table 45 moves on the surface plate 3 in a non-contact manner.

FIG. 8 shows a supporting and driving mechanism of the carriers (stator carriers 8A and 8B and stators 16A, 16B and 33) of this embodiment. In FIG. 8, these supporting and driving mechanisms are as follows. It is arranged so as not to contact the surface plate 3 of FIG. Therefore, the platen 3 is composed of the movable table 4
Since only the load of No. 5 needs to be supported, the anti-vibration effect can be enhanced.

Next, returning to FIG. 1, a projection optical system PL and a reticle R are sequentially arranged above the wafer W, and the projection optical system PL is located at the lowest stage of the column 34 fixed on the surface plate 3. The reticle R is fixed to a support plate 34a, and the reticle R is movably mounted on a reticle base 35 fixed on a middle support plate 34b of the column 34.
6. The optical axis AX of the projection optical system PL is Z
Parallel to the axis. Also, on the upper plate 34c of the column 34,
For example, an illumination optical system including a fly-eye lens, a variable field stop (reticle blind), a condenser lens, and the like for equalizing the illuminance distribution of exposure light from an exposure light source installed outside a chamber in which the projection exposure apparatus is housed. 37
During exposure, the exposure light from the illumination optical system 37 illuminates the pattern area of the reticle R with a rectangular illumination area elongated in the X direction. As the exposure light IL, in addition to an emission line such as an i-line of a mercury lamp, an excimer laser beam such as KrF (wavelength 248 nm) or ArF (wavelength 193 nm),
Further, soft X-rays or the like can be used. Then, the image of the pattern in the illumination area is converted into a projection magnification β via the projection optical system PL.
(Β is, for example, １ ／ times, ５ times, etc.), and is transferred to a rectangular exposure area 24 on the wafer W (see FIG. 2). A photoresist is applied on the surface of the wafer W, and the surface of the wafer W is projected onto the projection optical system PL by the Z leveling stage 20.
Is held so as to coincide with the image plane of.

Further, a laser interferometer (not shown) for measuring the two-dimensional position of the reticle stage 36 is also provided, and a main control system 51 for supervising and controlling the measured values of the laser interferometer and the operation of the entire apparatus. The stage control system 52 controls the operation of the reticle stage 36 by a linear motor system in accordance with the instruction of the above. Similarly, the laser interferometer 21XA of FIG.
The measured values of 21XB and 21Y are also used in the stage control system 52 of FIG.
The stage control system 52 is supplied to the wafer stage side in accordance with the measurement value and a command from the main control system 51.
-Axis fixed carrier drive motors 10A, 10B, 2-axis Y
The operation of the axis motors 18A, 18B and the X-axis motor 31 is controlled.

Next, the configuration of the stage control system 52 of this embodiment will be described. FIG. 9 shows the stage control system 52 shown in FIG.
In FIG. 9, the stage control system 52 includes a wafer stage drive system 53 and a reticle stage drive system 54 each composed of a computer, and various drivers. Then, the measured values of the laser interferometer 29X on the stator carrier side and the measured values of the three-axis laser interferometers 21XA, 21XB, 21Y on the wafer stage side are supplied to the wafer stage drive system 53, and are supplied to the wafer stage drive system 53. Is the sample table 2 from the main control system 51.
Command values such as a target position and a moving speed of 2 (wafer W) are supplied. By inserting the measured value of the laser interferometer 29X on the stator carrier side, the stator carrier 8 and the table 4
5 can be recognized. Therefore, the table 45 can be stopped or moved to an arbitrary position within a relative movable range regardless of the moving speed of the carrier 8 in the X direction.

In accordance with the information, the wafer stage drive system 53 operates the fixed carrier drive motors 10A and 10A shown in FIG.
The thrusts generated by the B and Y-axis motors 18A and 18B and the X-axis motor 31 in FIG. 1 are set, and information on these thrusts is supplied to the drivers 55A, 55B, 56A, 56B and 57. Further, wafer stage drive system 53 supplies synchronization information to reticle stage drive system 54, and reticle stage drive system 54 drives reticle stage 36 in synchronization with the wafer stage.

Drivers 55A and 55 on the wafer stage side
B and 56A, 56B supply driving current to the coils of the movers 11A, 11B and the coils of the stators 17A, 17B so as to generate a set thrust. Similarly, the driver 57 supplies a drive current to the coil 32a of the mover 32 of the corresponding X-axis motor 31. Next, a configuration example of the Z leveling stage 20 of the present example will be described with reference to FIGS.

FIG. 10 shows the Z leveling stage 20.
FIG. 11 is a cross-sectional view taken along the line AA in FIG. 10. First, as shown in FIG. 10, the sample stage 22 on which the wafer W is mounted is formed of ceramics or carbon fiber or the like. I have. The sample stage 22 moves in the Z direction within a predetermined range and tilts through three leaf springs 120a to 120c on the disk-shaped support 100 constituting the Z leveling stage 20 as described later. Supported to be able. The configuration around the leaf springs 120a to 120c is the same as each other, and the numbers indicating the corresponding members are given subscripts a to c, respectively.

In FIG. 11, Z leveling stage 2
The support member 100 constituting the base member 0 is formed of ceramics or carbon fiber in order to increase rigidity and reduce weight. In the concave portion 100b at the center of the support 100,
Three two-pole single-phase linear motor units (hereinafter, referred to as “LDM”) 156a to 1 having the same configuration, which are electromagnetic drive devices
56c are installed at 120 ° intervals around the center of the recess 100b. These LDMs 156a to 156c are respectively arranged on the bottom surfaces of the leaf springs 120a to 120c in FIG.

The LDM 156a is composed of a stator 151 having a single-phase coil 159 and installed on the concave portion 100b, and a movable element 158 as a yoke which is arranged so as to sandwich the stator 151 and has a permanent magnet installed on the inner surface. It is configured. That is, the permanent magnets 155a, 157a are fixed to one inner surface of the mover 158 so that the polarity is reversed in the Z direction, and the permanent magnets 155b, 157b is fixed. As the permanent magnet, a cobalt type, a nickel type, a neodymium iron boron type, or the like can be used. As a result, the direction of the magnetic flux generated between one pair of permanent magnets 155a and 155b is changed to the other pair of permanent magnets 157.
The direction of the magnetic flux generated between a and 157b is reversed, and a single-phase coil 159 is inserted between these two pairs of permanent magnets in a non-contact manner.

In this case, the current flowing through the single-phase coil 159 is a portion 15 between the pair of permanent magnets 155a and 155b.
9b and a portion 159a between another pair of permanent magnets 157a, 157b are opposite to each other, and a thrust of Lorentz force acts on the mover 158 in the + Z direction between the permanent magnets 155a, 155b. Then, the permanent magnet 157
A thrust of Lorentz force acts on the mover 158 in the + Z direction even between a and 157b. Since the Lorentz force is proportional to the value of the current flowing through the single-phase coil 159, the thrust acting on the mover 158 in the Z direction can be controlled by controlling the current. Other LDMs 156c and the like can similarly control the thrust of the corresponding mover in the Z direction.

The leaf spring 12 is disposed between the upper surface of the mover 158 of each of the LDMs 156a to 156c and the flanges 131a to 131c provided at the bottom of the sample table 22, respectively.
0a to 120c are sandwiched between the leaf springs 120a to 120c.
The other end of 120c is the concave portion 100b of the support 100, respectively.
Is screwed to a stepped portion 100a provided on the upper side. The leaf springs 120a to 120c are formed of a metal plate that is thin and long in the horizontal direction (XY plane direction) such as stainless steel, and the leaf springs 120a to 120c are rotated in the horizontal direction (X direction, Y direction, and rotation direction around the Z axis). And the rigidity is low in directions other than the horizontal direction (the Z direction, the rotation direction around the X axis, and the rotation direction around the Y axis. The leaf spring 12).
Oa to 120c allow the sample table 22 to be flexible in the Z direction with respect to the support 100 and to be held in such a manner that tilting around the X axis and the Y axis is possible within a predetermined range. Further, the LDMs 156a to 156c
, Height detectors 152a to 152c each including a capacitance sensor or the like are installed in the vicinity of. Height detector 15
2a to 152c measure the displacement of the sample stage 22 with respect to the support 100 in the Z direction.

Further, rectangular plate-like mounting members 153a to 153c are screwed to the upper surface of the support 100 so as to face the flange portions 131a to 131c, respectively. Further, as shown in FIG.
Fan-shaped covers 154a to 154c are screwed onto the support 100 so as to cover the gaps from 153 to 153c. FIG.
1, a pair of permanent magnets 115 and 117 (cobalt-based, nickel-based, neodymium-iron-boron-based, ) Are attached, and permanent magnets 114 and 116 are attached to the bottom surface of the attachment member 153a via the yoke 116 so as to face the permanent magnets 115 and 117 and have polarities that attract the permanent magnets 115 and 117, respectively. Yoke 11
6, 118, permanent magnets 114, 116, and permanent magnet 1
15, 117 constitute a suction unit 109a, between the flange portion 131a and the mounting member 153a.
In addition to the suction unit 109a, as shown in FIG. 10, a suction unit 110a having the same configuration as the suction unit 109a
To 112a, and these suction units 109a
To 112a, the flange 131a of the sample stage 22
Is pulled up toward the mounting member 153a (+ Z direction).

Similarly, the other flanges 13 of the sample stage 22
1b and 131c are also suction units 109b-11.
2b and the mounting members 153b, 153c corresponding to the suction units 109c to 112c (+ Z direction)
Has been raised. Therefore, in this example, the leaf spring 12
0a to 120c and LDMs 156a to 156c have Z
There is almost no load in the direction, and the LDMs 156a to 1
From 56c, the leaf springs 120a to 120c, and the + Z direction for adjusting the levitation force with respect to the sample stage 22, or-
The focus position and the tilt angle of the sample stage 22 can be controlled only by applying a thrust in the Z direction.
Although not shown in FIG. 11, an oblique incidence type auto focus sensor for detecting focus positions at a plurality of measurement points on the surface of the wafer W is provided in FIG. 11, and the detection result and the height detector are provided. By controlling the thrusts of LDMs 156a to 156c based on the measurement results of 152a to 152c, the surface of wafer W can be projected onto projection optical system P in FIG.
L is held so as to match the image plane of L.

Next, the exposure operation of the projection exposure apparatus of this embodiment will be described. First, at the time of scanning exposure, when exposure to one shot area on the wafer W is completed in FIG.
X-axis motor 31 and Y-axis motors 18A and 18B of FIG.
At least one of them is stepped to move the next shot area to the scanning start position. At this time, if the stepping direction is the X direction, the fixed carrier driving motor 10
A and 10B are also driven continuously. Thereafter, the Y-axis motors 18A and 18B are driven at a constant speed, and the reticle stage 36 shown in FIG. Synchronous scanning is performed as a speed ratio. by this,
One shot area 25 on the wafer W is scanned in the Y direction with respect to the rectangular exposure area 24, and the pattern image of the reticle R is transferred to the shot area 25. This stepping and scanning exposure operation is repeated in a step-and-scan manner, so that each shot area of the wafer W is exposed.

During such an exposure operation, if the next shot area to be exposed is a shot area in a column (or row) adjacent in the X direction (non-scanning direction), stepping between the next shots is performed. During scanning exposure, the movable table 4 of FIG. 3 is operated so that the operation is substantially performed only by the X-axis motor 31.
5, and the carriers (stators 16A, 16B, 33, stator carriers 8A, 8B) are integrally moved in the X direction via fixed carrier drive motors 10A, 10B. However,
At this time, the movable table 45 is moved in the opposite direction via the X-axis motor 31 relative to the carrier so that the position of the movable table 45 (wafer W) in the X direction does not shift. Hereinafter, the operation at this time will be described in detail with reference to FIG.

FIG. 12 is a view for explaining an operation in the case where scanning exposure is sequentially performed on the shot areas 25A to 25C arranged in the X direction on the wafer W. W is scanned in the ± Y direction. In FIGS. 12A to 12G, the exposure region 24 is shown to move on the wafer W for convenience of explanation. Further, the positions A and B in the X direction in FIGS. 12A to 12G correspond to the carriers (stators 16A and 16A) in FIG.
B, 33, the position of the stator carrier 8A, 8B) in the X direction, and the position of the movable table 45 (and thus the wafer W) in the X direction. Also, of course, the exposure area 2
In No. 4, exposure light is irradiated during a period within the shot regions 25A to 25C, but is not irradiated during other periods.

First, as shown in FIGS. 12A to 12C, the Y-axis motors 18A and 18B are driven to
By moving the movable table 45 (hereinafter referred to as “moving the wafer W”) in the + Y direction with respect to 4, the scanning exposure to the + X direction shot area 25A on the wafer W is performed. At this time, the carriers (stators 16A, 16B, 33, stator carriers 8A, 8B) are driven at a constant speed VXC in the + X direction by driving the fixed carrier drive motors 10A, 10B in FIG. And the X-axis motor 31 is driven to move the wafer W with respect to the carrier at the same speed VXC in the −X direction. As a result, as shown by the fixed position B, during the scanning exposure to the shot area 25A, the X
The position of the direction is fixed. Further, the wafer W moves to the end in the −X direction during the movable stroke of the width DX (see FIG. 4) with respect to the carrier.

Thereafter, the next shot area 2 on the wafer W
In order to move 5B to the scanning start position, the X-axis motor 31 is driven to move the wafer W stepwise in the + X direction at the highest speed, as shown in a position B in FIGS. 12C and 12D. In this example, at this time, the fixed carrier drive motors 10A and 10B in FIG. 3 are also continuously driven, and the carrier is slightly moved in the + X direction as shown by the position A.

Next, in the state shown in FIG. 12D, the wafer W has moved to the end in the + X direction during the movable stroke (see FIG. 4) with respect to the carrier, and moves in the next + X direction. Cannot secure the moving amount at the time of stepping. Therefore, as shown in FIGS. 12D to 12F, the Y-axis motors 18A and 18B are driven to move the wafer W in the −Y direction with respect to the exposure region 24, so that the center of the wafer W 3 is driven by the fixed carrier drive motors 10A and 10B shown in FIG.
6A, 16B, and 33, and the stator carriers 8A and 8B) are moved in the + X direction at a constant speed VXC, and the X-axis motor 31 is driven.
At the same speed VXC in the −X direction. As a result, while the position of the wafer W in the X direction is fixed during the scanning exposure to the shot area 25B, the position of the wafer W with respect to the carrier moves to the end in the −X direction during the movable stroke.

Thereafter, the next shot area 2 on the wafer W
In order to move 5C to the scanning start position, the X-axis motor 31 is driven to move the wafer W stepwise in the + X direction at the highest speed, as shown at the position B in FIGS. 12 (f) and 12 (g). At this time, the fixed carrier driving motors 10A, 10A of FIG.
10B is also driven continuously, and as shown by position A, its carrier is also slightly moving in the + X direction. Hereinafter, when sequentially exposing the shot areas of the row adjacent to each other in the X direction on the wafer W, the carrier is continuously driven in the X direction at a constant speed via the fixed carrier driving motors 10A and 10B. The (wafer W) is driven like an pendulum in the X direction relative to the carrier by the X-axis motor 31.

As described above, in the present example, the load when the wafer W is step-moved in the X direction (non-scanning direction) via the X-axis motor 31 is extremely light as the movable table 45 alone. It can be performed in a very short time and with high accuracy. Further, since the movable table 45 is disposed on the surface plate 3 via the static pressure air bearing, the resistance when moving is almost the only inertial force of the movable table 45, and the load when driving is extremely small. Has become. As a result, in the projection exposure apparatus of the present example, only the movable table 45 is to be positioned with high accuracy in both the X and Y directions, so that the load in a predetermined direction is twice as large as in the conventional case. Therefore, the moving speed in that direction does not decrease.

In other words, the load when stepping in the X direction is the same as the load when driving the movable table 45 in the Y direction with respect to the carrier via the Y-axis motors 18A and 18B. The moving time when the movable table 45 (wafer W) is step-moved in the Y direction is also extremely short. That is, in this example, the load at the time of stepping the movable table 45 (wafer W) in the X direction and the Y direction is lightened to the same extent, and the step time can be reduced, so that the throughput of the exposure process can be improved. is there.

Further, in this example, when the X-axis motor 31 moves the wafer W stepwise in the X direction, the fixed carrier drive motors 10A and 10B also move the carrier as a whole in the X direction. The amount of drive by the shaft motor 31 is reduced, the time required for stepping is further reduced, and the throughput is further improved. Also,
In FIG. 1, the reaction force generated on the stator 33 when the X-axis motor 31 is driven is fixed by the fixed carrier driving motor 10 shown in FIG.
A, 10B transmitted to the floor via the Y-axis motor 18
The reaction force generated on the stators 16A, 16B when the A, 18B is driven is transmitted to the floor via the static pressure air bearings of the stator carrier sliders 7A, 7B. Accordingly, since the driving reaction force is not transmitted to the surface plate 3 directly connected to the projection optical system PL, the laser interferometers 21XA, 21XB, etc., the surface plate 3 does not vibrate when the movable table 45 is accelerated or decelerated.
The positioning accuracy is improved.

Further, in the conventional wafer stage, the amount of heat generated by the drive motor is large because the entire movable portion rapidly accelerates and decelerates between shots each time one shot is exposed. Only the lightweight movable table 45 moves stepwise between shots, and the carrier composed of the stator carriers 8A and 8B and the stators 16A, 16B and 33 only needs to move at a constant speed at all times.
The amount of heat generated by the drive motor can be kept low.

In the above embodiment, the movable table 45 (the sample table 2) is fixed to the stator carriers 8A and 8B.
2, or an X-axis motor 31 for driving the wafer W) in the X direction
Is a single axis, the stator 33 of the X-axis motor 31
It is desirable to pass through the vicinity of the position of the center of gravity of the movable table 45 in the X direction. On the other hand, the X-axis motor 31
Two or more driving devices similar to the above may be arranged in parallel with the Y axis. For example, when the X-axis driving devices are arranged in two axes, the Y-axis motors 18A and 18B can be configured to arrange only one of the axes.

In the above embodiment, the present invention is applied to a wafer stage of a step-and-scan type projection exposure apparatus, but the present invention is applied to a batch exposure type (step-and-scan type) such as a stepper. The present invention can be applied to a wafer stage of a (repeat type) exposure apparatus and also to a reticle stage and the like. As described above, the present invention is not limited to the above-described embodiment, and can take various configurations without departing from the gist of the present invention.

[0059]

According to the first or second stage control method of the present invention, for example, when a table is moved within a predetermined range, only the table is driven relatively to the carrier. Because it is good, the mass to be driven can be reduced.
Therefore, when the table on which the positioning target is placed is moved in two directions on a two-dimensional plane, there is an advantage that the moving speed can be increased in any direction.

When the present invention is used in a scanning exposure apparatus, the direction in which the carrier is driven as a whole is set to the non-scanning direction, and the carrier is continuously driven in the non-scanning direction during the scanning exposure. By doing so, when driving the table in the non-scanning direction between shots, only the table needs to be driven. Therefore, there is an advantage that the stepping time is shortened and the throughput of the exposure step can be increased.

According to the stage apparatus of the present invention, there is an advantage that the stage control method can be used. In this case, the carrier is mounted on a predetermined base that defines a two-dimensional plane, and when the table is mounted on the base via a hydrostatic gas bearing, resistance when the table moves is reduced. Since the table is extremely small, there is an advantage that the table can be driven at a higher speed in any direction.

Further, according to the first or second exposure apparatus of the present invention, the stepping time between shots can be reduced, so that a high throughput can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a projection exposure apparatus used in an example of an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view showing a wafer stage of the projection exposure apparatus of FIG.

FIG. 3 is a partially cutaway perspective view showing a state in which a Z leveling stage 20 is mounted on the wafer stage of the projection exposure apparatus of FIG.

FIG. 4 is a plan view showing a movable table 45 and a carrier in FIG. 3;

5 (a) is a partially cutaway plan view showing the X-axis motor 31 of FIG. 1, and FIG. 5 (b) is a side view of FIG. 5 (a).

FIG. 6A is a plan view showing a modification of the X-axis motor 31, and FIG. 6B is a side view of FIG. 6A.

7 is an exploded perspective view showing a movable table 45 that moves integrally on a surface plate 3 in a wafer stage of the projection exposure apparatus of FIG.

8 is a perspective view showing a carrier support mechanism and a drive mechanism in the wafer stage of the projection exposure apparatus of FIG.

FIG. 9 is a block diagram illustrating a configuration example of a stage control system 52 according to an example of the embodiment.

FIG. 10 is an enlarged plan view showing the Z leveling stage 20 of FIG.

11 is a sectional view taken along the line AA in FIG.

FIG. 12 shows shot areas 25A to 25 arranged in a X direction on a wafer W by a projection exposure apparatus according to an example of the embodiment.
FIG. 9 is an operation explanatory diagram when scanning exposure is performed on C.

[Explanation of symbols]

 R Reticle W Wafer PL Projection optical system 2A to 2C Anti-vibration table 3 Surface plate 4A, 4B Guide for stator carrier 8A, 8B Stator carrier 5A, 6A, 6B Stator carrier support 7A, 7B For stator carrier Slider 10A, 10B Fixed carrier drive motor 11A, 11B Mover 11A 12A, 12B Stator 12A 14 XY moving table 16A, 16B Stator 17A, 17B Mover 18A, 18B Y axis motor 20 Z leveling stage 22 Sample stage 31 X axis Motor 32 mover 33 stator 52 stage control system

Claims (6)

[Claims] 1. A stage control method for moving a table on which a positioning target is placed on a two-dimensional plane, comprising: a carrier for moving the table two-dimensionally within a predetermined moving range; A stage control method, comprising: moving the carrier in a predetermined one-dimensional direction on the two-dimensional plane when moving the table to a wider range. 2. A stage apparatus for moving a table on which a positioning object is placed on a two-dimensional plane, wherein the table is held by electromagnetic force and the table is two-dimensionally moved within a predetermined moving range. A stage apparatus comprising: a carrier to be moved; and a driving unit that moves the carrier in a predetermined one-dimensional direction on the two-dimensional plane. 3. The stage device according to claim 2, wherein the carrier is mounted on a predetermined base that defines the two-dimensional plane, and the table is mounted on the base via a static pressure gas bearing. A stage device characterized in that it is made. 4. A table on which a substrate as an object to be positioned is placed and supported movably on a two-dimensional plane, and the substrate is moved through the table in a first direction on the two-dimensional plane. In synchronization with the movement of the mask, the mask is moved in a corresponding direction, thereby scanning and exposing the pattern of the mask on a first shot area on the substrate. In an exposure apparatus, the step moves in at least one of a second direction crossing a first direction and at least one of the first directions to start scanning exposure on a second shot area on the substrate. Holding the table by electromagnetic force, the table is moved in the first direction within a range covering the exposure range on the substrate, and is moved in the second direction within an adjacent shot area on the substrate. A carrier that moves within a range of a distance or more, a driving unit that moves the carrier together with the table in the second direction within a range that covers an exposure range on the substrate, a control unit of the carrier and the driving unit, When the second shot area is located in a row adjacent to the first shot area in the second direction, the control means: the first shot area on the substrate Moving the carrier in the second direction via the driving means in parallel with moving the substrate in the first direction via the carrier during scanning exposure to the first shot area; An exposure apparatus for moving the table stepwise in at least the second direction via the carrier after the exposure of the table. 5. An exposure apparatus for exposing a pattern of a mask onto a substrate, comprising: a main body having a table on which the substrate is placed, the main body being supported from a floor surface via vibration isolating means, and moving the table in a two-dimensional plane. An exposure apparatus, comprising: a carrier to be moved; and a driving unit provided separately from the main body and moving the carrier in a one-dimensional direction in the two-dimensional plane. 6. A stage control method for moving a table on which a positioning object is placed on a two-dimensional plane, wherein a position of the table in a first direction and a position in a second direction orthogonal to the first direction are measured. And a step of positioning the table by measuring a position of the carrier that moves the table on a two-dimensional plane in the first direction.