JP2001057325A - Stage device and aligner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device of a structure, wherein a control of the position and attitude of a stage can be exercised under the non-air environment, and at the same time a miniaturization and lightening of the stage are made possible. SOLUTION: A stage WST is two-dimensionally driven with an electromagnetic force along the moving surface of a first driving unit 31 by the unit 31, and is driven with a magnetic force in the direction on at least the one side of the Z-axis direction intersecting orthogonally the moving surface and the leveling direction by a second driving unit 32. Accordingly, it becomes possible that the stage WST is driven with the electromagnetic force in the three freedom directions within the moving surface by the unit 31, and the stage WST is driven with the magnetic forces in the remaining three freedom directions. As a result, a control of the position and attitude of the stage WST becomes possible without hindrance even under the non-air environment. Moreover, a leveling table, an air bearing and the like become useless and a miniaturization and a lightening of the stage WST become possible. Accordingly, the enhancement of the controllability of the position of the stage WST becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a stage device and an exposure apparatus, and more particularly, of course in the air atmosphere, nitrogen gas (N _2), helium gas (the He), or a non-air environment such as vacuum The present invention also relates to a stage device for controlling the position and orientation of a control target object with high accuracy, and an exposure apparatus including the stage device.

[0002]

2. Description of the Related Art Conventionally, in a lithography process for manufacturing a semiconductor device, a liquid crystal display device, or the like, a pattern formed on a mask or a reticle (hereinafter, collectively referred to as a “reticle”) is resisted through a projection optical system. There is used an exposure apparatus that transfers the image onto a substrate such as a wafer or a glass plate coated with a substrate. In this type of exposure apparatus, it is necessary to sequentially transfer the pattern formed on the reticle to a plurality of shot areas on the wafer while positioning the wafer at the exposure position with high precision, so a stage provided with a wafer holder holding the wafer is provided. Is provided.

Recently, in order to control the two-dimensional position of a wafer at a higher speed and with high accuracy without being affected by the accuracy of a mechanical guide surface, etc., and to avoid mechanical friction and extend the life of the wafer. , a two-dimensional direction of the wafer is placed a table in a non-contact by driving in the (X-direction, directions of three degrees of freedom in the Y direction, and theta _{Z-direction),} the stage apparatus is developed to perform XY2 dimensional position control of the wafer Have been. As a drive source of such a non-contact drive stage device, a planar motor of a variable reluctance drive system or a planar motor of an electromagnetic drive system using Lorentz force is used.

At present, variable magnetoresistive drive type planar motors capable of obtaining a large driving force are predominant. As such variable magnetoresistive drive type planar motors, variable magnetoresistive drive type linear pulse motors such as soyer motors are used. Are used in many cases. The variable pulse motor of the variable reluctance drive system includes, for example, a stator formed of a plate-shaped magnetic body having uneven tooth portions formed at regular intervals along a longitudinal direction, and an uneven shape of the stator. A mover is provided with a plurality of armature coils opposed to the teeth and having irregularities having phases different from those of the irregular teeth, which are connected via permanent magnets. Then, the mover is driven by using a magnetic force generated in an attempt to minimize the magnetic resistance between the stator and the mover at each time. That is, the mover is moved stepwise or at a constant speed by adjusting and controlling the current value and phase of the pulse current supplied to each armature coil.

On the other hand, in the electromagnetic driving method, the theoretical design based on the Lorentz force is easy, and the linearity of the current and the thrust is good up to a high band. The planar motor adopting the electromagnetic driving method has been developed (for example,
Conventionally, it has been difficult to obtain a driving force comparable to that of the variable magnetoresistive driving method (see U.S. Pat. No. 519745). However, the performance of permanent magnets has been remarkably improved in recent years, and high-performance magnets having an energy product of 40 MGOe or more have become available.

[0006]

[0005] In a planar motor as described above, X, Y, in order to perform a non-contact position and posture control of the directions of three degrees of freedom theta _Z, from the viewpoint of easiness in levitation support control A static pressure air bearing is generally employed as a floating support mechanism.

By the way, in the stage apparatus for controlling the position and orientation of the wafer, X, Y, in addition to the position and posture control of the directions of three degrees of freedom theta _Z, Z, theta _X, three degrees of freedom of theta _Y It is necessary to further perform position / posture control regarding the direction. The position in the three degrees of freedom of Z, θ _X and θ _Y
In performing the attitude control, since the responsiveness of the static pressure air bearing is difficult, it is difficult to control the position and attitude in the three degrees of freedom of Z, θ _X , and θ _Y by the air pressure control. For this reason, at present, a Z-leveling table capable of controlling the position and orientation in three degrees of freedom of Z, θ _X , and θ _Y is usually mounted on the stage. In such a stage device, the weight of the movable portion is large, and a high thrust motor is required as a linear motor to obtain the required acceleration. Also,
Due to the large size of the movable part, the degree of freedom in design was also limited.

Further, with the miniaturization of device rules (practical minimum line width) accompanying the high integration of semiconductor devices, an exposure apparatus has been required to have an even higher resolution as a performance. For this reason, the exposure wavelength has been shortened, and as a next-generation or later exposure apparatus, vacuum ultraviolet (VUV) light having a wavelength of 200 nm or less, or a charged particle beam such as an X-ray having a shorter wavelength or an electron beam. Has to be used as an energy beam for exposure. In such an exposure apparatus, if air is present in the energy beam path, a cloudy substance or an energy beam absorbing substance such as ozone O ₃ is generated by a photochemical reaction, or the energy beam is directly absorbed by air molecules. Nitrogen N ₂ or helium He
For example, it is necessary to replace the air with a gas or to create a vacuum environment.

On the other hand, the stage device which floats and supports the Z-leveling stage by the above-mentioned static pressure air bearing system is basically limited to use under atmospheric pressure. It is difficult to use in a vacuum environment.

The present invention has been made under such circumstances, and a first object of the present invention is to control the position and attitude of the stage without any trouble even in a non-air environment and to simplify the structure of the stage. It is an object of the present invention to provide a stage device that can be made smaller and smaller and lighter.

A second object of the present invention is to provide an exposure apparatus capable of improving the throughput.

[0012]

A stage apparatus according to the present invention comprises a stage (W) having a mounting surface on which an object (W) is mounted.
ST) and; a first driving device for driving an electromagnetic force along the moving surface of the stage (31); disposed on the stage, adjusting device for adjusting the magnetic force (80 ₁ to 80 ₄₎ A second driving device (32) for driving the stage with a magnetic force in a direction intersecting with the moving surface.

According to this, the stage is driven by the first driving device by the electromagnetic force along the moving surface, and is driven by the second driving device by the magnetic force in a direction intersecting the moving surface. Here, “driving along the moving surface” means that the stage is driven in a predetermined uniaxial direction, a perpendicular biaxial direction, or a perpendicular biaxial direction in a plane parallel to the moving surface, and a rotating direction in the plane. In both cases, "driving in the direction intersecting with the moving surface" means not only changing the position along the direction intersecting with the moving surface while maintaining the posture of the stage, but also the posture. And driving the stage in a direction intersecting the moving surface so as to change

Therefore, the stage can be driven by the first driving device with electromagnetic force in three directions of freedom in the moving plane, and can be driven by the second driving device with magnetic force in the remaining three directions of freedom. Accordingly, the position and orientation of the stage can be controlled without any trouble even in a non-air environment. Further, a Z-leveling table, an air bearing, and the like are not required, and the size and weight of the stage can be reduced, thereby improving the position controllability of the stage. Here, the electromagnetic force is synonymous with the Lorentz force and is defined by F = BIL (B: magnetic flux density, I: current, L: coil length). The magnetic force refers to a force that causes two objects having magnetic poles to pull or repel each other.

In the stage device according to the present invention, the first driving device includes a movable element (60) provided on the stage so as to face the moving surface; and an electromagnetic interaction between the movable element (60) and the movable element. And a stator (50) for driving the stage. In such a case, the stage is driven together with the mover along the moving surface by electromagnetic interaction between the stator and the mover. When the adjusting device adjusts the magnetic force on the mounting surface side of the stage (opposite to the moving surface), the magnetic force in the axial direction orthogonal to the moving surface and the inclination direction (pitching direction, rolling direction) with respect to the moving surface is adjusted. The stage is driven in at least one direction.

Here, the mover is an armature unit (6
1), wherein the stator has a magnetic pole unit (50). In such a case, the amount of the magnetic flux generated by the magnetic pole unit, which is the source of the magnetic flux near the armature unit in the first drive unit, mixed into the magnetic circuit for generating the magnetic force in the second drive unit, It can be reduced as compared with the case where the mover has a magnetic pole unit and the stator has an armature unit.
Therefore, stable floating support control of the mover is possible.

In order to reduce the amount of magnetic flux caused by the magnetic pole unit mixed in the magnetic circuit for generating a magnetic force in the second driving device, the armature unit is connected via a magnetic member having a magnetic shielding effect. It is preferable that the stage is supported by the stage. In such a case, a magnetic attractive force acts between the magnetic pole unit of the stator and the magnetic member supporting the armature coil, so that the floating rigidity of the mover can be increased.

Further, in the stage device of the present invention, a container member (67) in which a storage space for storing the armature unit is formed; cooling for supplying a refrigerant to the storage space to cool the armature coils; And a device (18). In such a case, when the driving force is generated, the heat generated in the armature coil due to the current being supplied to the armature coil is removed by the refrigerant supplied from the cooling device. Diffusion of heat to the periphery of the armature coil can be suppressed. Therefore, it is possible to reduce the change in the efficiency of generating the driving force due to the rise in the temperature of the armature coil, the occurrence of thermal expansion due to the transfer of heat to members and devices around the armature coil, and the occurrence of fluctuation in the atmosphere around the stage. be able to.

Here, the armature unit may include a plurality of armature coils, and may further include a coil supporting member for supporting the plurality of armature coils apart from the stage. In such a case, the heat generated by the armature coil does not directly conduct to the stage, but only to the stage via the coil support member, and reduces the contact area between the refrigerant and the armature coil. Since it can be increased, the heat generated in the armature coil can be efficiently removed, and the amount of heat generated in the armature coil transmitted to the stage can be reduced.

[0020] In the stage device of the present invention, the adjusting device is disposed on the mounting surface of the stage, at least three magnet body having substantially parallel pole surface and the mounting surface (80 ₁ to 80 ₄₎ And the second driving device may include a flat magnetic member (85) opposed to a magnetic pole surface of the magnet body. In such a case, the adjusting device adjusts a magnetic force (magnetic attraction force) between each magnet body and the plate-shaped magnetic material member facing the magnetic pole surface, so that an axial direction orthogonal to the moving surface is provided. And the stage can be driven in any of the directions of rotation about two orthogonal axes in the moving plane.

In this case, it is sufficient that at least three magnets and three magnetic pole parts are provided, respectively, but the stage has a square shape, and the magnet body is provided at each of four corners on the mounting surface side of the stage. One arrangement may be adopted. In such a case, the magnetic force between two adjacent magnet bodies and the plate-shaped magnetic body and the magnetic force between the remaining two adjacent magnet bodies and the plate-shaped magnetic body are simultaneously increased and decreased. Accordingly, the stage can be driven only in the tilt direction without substantially changing the position of the stage.

Various configurations are conceivable as the configuration of the magnet body, and the magnet body is composed of electromagnets (82a, 82a).
b). In such cases,
By adjusting the current supplied to each electromagnet, the magnetic force between each magnet body and the flat magnetic body can be adjusted.

In this case, it is possible to generate a magnetic force between each magnet body and the plate-like magnetic body only by the electromagnet. However, the magnet body forms a permanent magnet (81) that forms a magnetic circuit with the electromagnet. ) Can be further included. In such a case, at least a part of the magnetomotive force as the magnet body serving as the source of the magnetic force required for the levitation support can be generated by the permanent magnet, so that the amount of current supplied to the electromagnet can be reduced. Electricity can be achieved.

Further, when no current is supplied to the electromagnet and the distance between each of the magnets and the flat magnetic member is a predetermined value, the stage and the movable The magnetic force may be set such that the vertical force acting on the whole of the magnet and the magnet body and the total magnetic force between the magnet body and the flat magnetic member are balanced. it can. In such a case, the stage can be held at a steady state position without adjusting the magnetic force, with the stage's own weight supported by the magnetic force. Therefore, adjustment of the position and orientation of the stage from the steady state can be realized with a small amount of energy.

When the magnet body has an electromagnet,
Said adjustment device is provided in at least three locations of the mounting surface of the stage, a gap sensor for detecting the gap amount between the plate-shaped magnetic member (86 ₁ to 86 ₄₎
And a current control device for controlling a current supplied to the electromagnet based on a detection result by the gap sensor. In such a case, the current controller controls the current supplied to the electromagnet based on the gap amount between the gap sensor and the flat magnetic body detected by the gap sensor, so that the axis perpendicular to the moving surface of the stage is controlled. The stage can be driven accurately with respect to the direction and the tilt direction with respect to the moving surface.

Here, the current controller controls the current supplied to the electromagnet based on a linear control model having a non-linear electromagnet model relating to the current supplied to the electromagnet and the detection result of the gap sensor. can do. In such a case, the levitation control is performed using a linear control model that becomes a linear levitation control system as a whole while keeping the relationship between the current supplied to the originally non-linear electromagnet and the detection result obtained by the gap sensor non-linear. The position (Z position) and attitude of the stage can be accurately controlled over a wide range.

[0027] In the stage apparatus of the present invention, the stage moves along the moving surface.
8); an object support member (89) provided on the table and supporting the object. Here, the object support member may be made of a magnetic shield material having a high magnetic permeability, or the stage may be attached to the object-side surface of the object support member, and the magnetic shield material may have a high magnetic permeability. And a magnetic shield member comprising: In such a case, it is possible to reduce the amount of magnetic flux used in the first driving device to enter the object mounting surface side of the object support member. Therefore, in exposing an object such as a substrate with a charged particle beam such as an electron beam, it is possible to prevent the charged particle beam from being deflected by magnetism, and to perform high-precision exposure.

When the object supporting member is provided, the object supporting member may be supported on the table at at least three places. In such a case, the smaller the contact area between the table and the support member, the better. This is because the amount of heat generated by the first drive device and the second drive device to the object support member via the table can be reduced.

The exposure apparatus of the present invention is an exposure apparatus for exposing a substrate (W) by an energy beam through an optical system (PL) and transferring a predetermined pattern onto the substrate, and the stage apparatus ( 30), wherein the stage constituting the stage apparatus is provided as a substrate stage for holding the substrate.

According to this, the position and orientation of the stage can be controlled without any trouble even in a non-air environment by the stage device of the present invention, and the stage can be simplified, and the size and weight can be reduced. . Accordingly, it is possible to increase the speed and acceleration of the stage, and to improve the throughput by shortening the positioning settling time and the like accompanying the improvement of the position control performance.

In the exposure apparatus according to the present invention, the first driving device constituting the stage device and the holding portion (43) holding the optical system may be configured to be independent with respect to vibration. In such a case, since the stator of the first drive device is independent of the holding portion holding the optical system with respect to vibration, the reaction force generated by the drive of the stage by the first drive device is generated by the optical system. This does not become a factor of the vibration, and the occurrence of a pattern transfer position shift or the like due to the vibration of the optical system can be prevented, so that high-precision exposure can be performed.

Further, the exposure apparatus of the present invention is configured to include a reaction force canceling mechanism (59) for canceling a reaction force generated by driving the substrate stage by the first driving device constituting the stage device. be able to. In such a case, the reaction force canceling mechanism cancels the reaction force generated by the driving of the substrate stage by the first driving device, so that the reaction force generated by the driving of the stage by the first driving device is generated by another component. Since it is not transmitted to the device or device and does not become a vibration factor, it is possible to prevent the occurrence of a pattern transfer position shift or the like due to the vibration of the optical system or the like, so that high-precision exposure becomes possible.

[0033]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
This will be described with reference to FIG. FIG. 1 schematically shows the configuration of an exposure apparatus 100 according to one embodiment. The exposure apparatus 100 is a step-and-scan type scanning exposure apparatus, that is, a so-called scanning stepper. As described later, in the present embodiment, the projection optical system P
In the following, the direction of the optical axis AX of the projection optical system PL is the Z axis, and the direction in which the reticle R and the wafer W are relatively scanned in a plane perpendicular to the axis is the Y axis. The description will be made with the direction orthogonal to the axis and the Y axis as the X axis.

The exposure apparatus 100 includes an illumination optical system 10,
A reticle stage RST for holding a reticle R as a mask, a projection optical system PL as an optical system, a main body column 43 as a holding unit for holding the projection optical system PL, and a stage for holding a wafer W as a substrate (or object) Wafer stage WST as X, Y, Z, θ _X , θ _Y ,
It includes theta _Z direction of the exposure apparatus main body comprising a 6 wafer stage apparatus 30 for driving the degrees of freedom, and their control system, and the like.

The exposure apparatus main body is actually housed in an unillustrated environmental chamber whose internal temperature and humidity are adjusted with high precision and is highly dust-proof. ₂ are filled. As an exposure light source of this exposure apparatus, an ArF excimer laser light source (not shown) that generates pulsed ultraviolet light having a wavelength of 193 nm is used. The ArF excimer laser light source, the main controller 20 and the stage control system 19 are actually installed in a service room with a lower degree of cleanliness than the ultra-clean room where the exposure apparatus 100 is installed. The excimer laser light source is connected to the illumination optical system 10 via a drawing optical system including a beam matching unit (not shown).

The illumination optical system 10 includes an illuminance uniforming optical system including a fly-eye lens, a relay lens, and a variable ND.
It is configured to include a filter, a reticle blind, a dichroic mirror and the like (all not shown). The configuration of such an illumination optical system is described in, for example,
No. 2433. This illumination optical system 10
The illumination light IL emitted from the reticle R on which a circuit pattern or the like is drawn after being reflected by the bending mirror M
The slit-shaped (rectangular or arc-shaped) illumination area portion IAR defined by the upper reticle blind is illuminated with substantially uniform illuminance.

A reticle R is fixed on the reticle stage RST by, for example, electrostatic attraction. The reticle stage RST is for controlling the position of the reticle R by a reticle stage drive unit (not shown) composed of a two-dimensional actuator or the like constituted by a magnetic levitation type linear motor using a Lorentz force or a reactance force on the reticle base 46. , Can be finely driven in an XY plane perpendicular to an optical axis IX of the illumination optical system 10 (coincident with an optical axis AX of a projection optical system PL described later), and in a predetermined scanning direction (here, Y direction). It can be driven at a specified scanning speed. The reticle base 46 constitutes a top plate of the gantry 41 constituting a main body column 43 described later.

The stator of the above-described two-dimensional linear actuator is supported by a reaction frame (not shown) provided independently of the reticle base 46. Therefore, when the reticle stage RST is driven, the reaction force acting on the stator of the two-dimensional linear actuator is transmitted to the ground (floor) by the reaction frame, and the reaction force is not transmitted to the recicle base 46.

The position of the reticle stage RST in the moving plane is determined by a reticle laser interferometer (hereinafter, “reticle interferometer”) which is a position detecting device fixed on the reticle base 14.
) Is always detected with a resolution of, for example, about 0.5 to 1 nm. The position information (or speed information) of the reticle stage RST from the reticle interferometer 16 is sent to the stage control system 19 and the main controller 20 via the stage control system 19, and the position of the reticle stage RST is sent to the stage control system 19 and the main controller 20. The reticle stage RST is driven via a reticle driving unit (not shown) based on the information.
In practice, the reticle interferometer 16 is provided with two axes in the scanning direction (Y-axis direction) and one axis in the non-scanning direction (X-axis direction). However, in FIG. 1
6 is shown.

The projection optical system PL is arranged below the reticle stage RST in FIG. 1, and its optical axis AX
The direction of (corresponding to the optical axis IX of the illumination optical system 10) is defined as the Z-axis direction. Here, a double-sided telecentric reduction optical system, and a plurality of lenses arranged at predetermined intervals along the optical axis AX direction Refractive optics consisting of elements are used. The projection magnification of the projection optical system PL is, for example, 1 /
5 (or 1/4, 1/6). Therefore, when the illumination area IAR of the reticle R is illuminated by the illumination light IL from the illumination optical system 10, the reticle in the illumination area IAR is transmitted by the illumination light IL passing through the reticle R via the projection optical system PL. A reduced image (partial inverted image) of the circuit pattern of R is coated on the surface of the wafer W with a photoresist.
An exposure area IA conjugate to the upper illumination area IAR is formed.

The main body column 43 includes a leg 45 described later.
A lens barrel base 42 horizontally supported by a vibration isolating table 44 provided on a table including a flat magnetic member 85;
And a gantry 41 fixed to the upper surface of the lens barrel base 42. The lens barrel base 42 has a circular opening formed in a central portion thereof in plan view, and the projection optical system PL is formed in the opening.
Are inserted from above. A flange portion FLG is provided at a central portion of the projection optical system PL in the height direction, and the projection optical system PL is connected to the lens barrel base 42 via the flange portion FLG.
Is supported from below.

The gantry 41 has four legs arranged vertically on the upper surface of the lens barrel base 42 so as to surround the projection optical system PL, and a space between the upper ends of these four legs. , A reticle base 46.

In the present embodiment, the micro vibrations transmitted from the floor FD to the main body column 43 are insulated at the micro G level by the four vibration isolation tables 44.

[0044] The stage device 30 includes a wafer stage WST for mounting the the wafer W, the wafer stage WST X, Y, the drive device 31 as a first driving device for driving the directions of three degrees of freedom theta _Z, When the wafer stage WST is Z,
A drive device 32 is provided as a second drive device that is driven in three degrees of freedom directions of θ _X and θ _Y. The driving device 31
The drive device 32 will be described later.

The side surface of wafer stage WST is mirror-finished so as to reflect a laser beam from a wafer laser interferometer (hereinafter, referred to as “wafer interferometer”) 35 as a position detecting device. The position of the wafer W in the XY plane is always detected by the fixed wafer interferometer 35 with a resolution of, for example, about 0.5 to 1 nm. Here, the position information (or speed information) of the wafer W is sent to the stage control system 19 and the main controller 20 via the stage control system 19, and the stage control system 19 sends the position information (or speed information) in response to an instruction from the main controller 20. Or speed information)
The driving device 31 is controlled. In practice, the wafer interferometer 35 is provided with one axis in the scanning direction and two axes in the non-scanning direction, but these are typically shown as the wafer interferometer 35 in FIG.

In the exposure apparatus 100, the projection optical system P
An irradiation optical system (not shown) for supplying an image forming light beam for forming a plurality of slit images toward the best image forming plane L from an oblique direction with respect to the optical axis AX direction, and a wafer W of the image forming light beam An oblique incidence type multi-point focal position detection system including a not-shown light receiving optical system that receives each reflected light beam on the surface through a slit is provided as a focus / leveling sensor. As this multi-point focal position detection system, for example, one having the same configuration as that disclosed in Japanese Patent Application Laid-Open No. Hei 5-190423 is used to detect a positional deviation of a plurality of points on the wafer surface in the Z direction with respect to the imaging plane. The wafer stage W is moved so that the wafer W and the projection optical system PL are kept at a predetermined distance.
It is used to drive ST in the Z and tilt directions. The wafer position information from the multi-point focal position detection system is sent to main controller 20. Main controller 20 determines the Z position and tilt amount (Δ
θ _X , Δθ _Y ), and the stage control system 19
Then, the wafer stage WST is driven in the Z direction and the tilt direction via the driving device 32 so as to be in a desired position and posture.

Further, the exposure apparatus 100 includes an alignment detection system (not shown) for detecting alignment marks (alignment marks) on the wafer. The detection result by the alignment detection system is sent to main controller 20. Main controller 20 controls the position of the wafer based on the mark information by using, for example, an EGA (Enhanced Global Alignment) technique. .

The driving device 31 includes a wafer stage WS
It includes a stator 50 incorporated in a base 47 provided below T, and a mover 60 provided on the lower surface of wafer stage WST.

The base 47 with the stator 50 incorporated therein
Is shown in FIG. 2 (A). The base 47 has a substantially square shape in a plan view, an upper surface and a lower surface are opened, and a frame member 48 made of a non-magnetic material having two steps formed on a side wall of an inner peripheral portion thereof. A flat plate-shaped magnet support member 53 made of a magnetic material is fitted to the lower step from above, and is fitted to the upper step of the frame member 48 from above. And a flat member 49 made of a non-magnetic material such as ceramic attached with the opening closed. The flat member 4
Reference numeral 9 is provided to protect permanent magnets 52N and 52S, which will be described later, disposed on the magnet support member 53, and may be omitted.

On the upper surface of the magnet support member 53, FIG.
As shown in (B), permanent magnets 52N and 52S having square-shaped magnetic pole surfaces each having a length of one side L are arranged alternately at a magnet interval L in a matrix. Here, the permanent magnet 52N is a permanent magnet having a magnetic pole surface which is a stage facing surface having an N pole, and the permanent magnet 52S is a permanent magnet having a magnetic pole surface which is a stage facing surface having an S pole. FIG.
In (B), the four permanent magnets arranged in a matrix are all permanent magnets 52N, but this is merely an example, and the permanent magnets arranged at one corner may be permanent magnets 52N. The permanent magnet 52S may be used, and the other 3
The type of corner permanent magnet is determined according to the type of permanent magnet arranged in one corner and the size of the permanent magnet arrangement area. The permanent magnets 5 arranged in a matrix
2N, 52S and the coil support member 53,
And the magnetic pole unit becomes the stator 50 of the driving device 31. Therefore, in the following description, the stator 50 is also referred to as a “magnetic pole unit 50”.

As shown in FIG. 3, the mover 60 includes a magnetic member 68 fixed to the lower surface of a table 88 constituting the wafer stage WST, and a non-magnetic member fixed to the lower surface of the magnetic member 68. Sixteen coil support members 65 made of a body material (see FIG. 4A), and sixteen armature coils 63 supported by the respective coil support members 65 in a state of being separated from the magnetic member 68 downward. And

The armature coils 63 are arranged in a matrix of 4 rows and 4 columns, as shown in FIG. Each armature coil 63 has a square shape with a length of 3 L on one side, and a hollow portion with a length of L on one side at the center in the XY cross section. And it is fixed to the coil supporting member 65 inserted in the hollow portion by an adhesive or the like.

The current supplied to each armature coil 63 is
It flows with a substantially uniform current density (volume density) around a central axis parallel to the Z axis of each coil. The current value and the current direction of the current flowing through the armature coil 63 are controlled by the main controller 20 via the stage control system 19. Note that the armature unit 61 in the drive device 31 is constituted by the above-mentioned 16 armature coils 63.

Further, below the wafer stage WST, a container member 67 forming a closed space for accommodating the armature unit 61 together with the magnetic member 68 is fixed to the magnetic member. Further, the container member 67 is provided with a refrigerant inlet 69a and a refrigerant outlet 69b. A refrigerant (for example, a fluorine-based inert liquid) is supplied from a cooler (not shown) through the inlet 69a. When it is sent into the space and passes through the internal space, it exchanges heat with the coil 63 to remove heat generated in the armature coil 63 due to current supply. As described above, since each armature coil 63 is supported by the coil supporting member 65 in a state of being separated downward from the magnetic member 68, the distance between each armature coil 63 and the magnetic member 68 is Refrigerant also flows in space. Therefore, the armature coil 6
The heat generated in 3 can be efficiently removed.

Returning to FIG. 1, the driving device 32 is provided above the wafer stage WST, and has a plate-like magnetic body having an opening formed in the center thereof as a passage for exposure light from the projection optical system PL to the wafer W. 85 and as shown in FIG.
Wafer stage magnet body 80 ₁ provided on the four corners of the upper surface of the WST, 80 _2, 80 _3, 80 ₄ (see FIG. 5 (In FIG. 1 shows only the magnet member 80 _2, 80 ₃₎ ). Here, the flat magnetic body 85 is held by four legs 45 erected on the ground (floor). In addition, the above-described four vibration isolation tables 44 are disposed on the upper surface of the flat magnetic body 85.

[0056] The magnet body 80 _1, 80 _2, 80 _3, 80 _4, respectively, as comprehensively shown by FIGS. 5 and 3 are magnetized in the X-axis direction, a rectangular parallelepiped shape fixed to the wafer stage And permanent magnets 81, and electromagnets 82a and 82b fixed to both ends of the permanent magnet 81 in the X-axis direction. Here, the electromagnets 82 a and 82 b have the same configuration, are each fixed to the magnetic pole surface of the corresponding permanent magnet 81, and have a rectangular parallelepiped magnetic core protruding above the upper surface height of the permanent magnet 81. The member 83 and the permanent magnet 8
1 and a coil 84 wound around a portion of the magnetic core member 83 protruding above the upper surface height.

[0057] That is, the magnet body 80 _1, 80 _2, 80 _3,
80 ₄ is configured as an offset type electromagnet having a magnetomotive force even when the respective currents are not supplied. The magnetomotive force of the permanent magnet 81 is such that the wafer stage WST is horizontal and the stages are magnet bodies 80 ₁ , 80 ₂ , 8
0 _3, when the distance between the 80 respective pole faces of the ₄ and the plate-shaped magnetic member 85 is a predetermined value, the wafer stage WST and the wafer stage WST and a mover 60 that moves integrally with the magnet body 80 ₁ , 80 _2, 80 _3, and gravity acting on the movable portion 80 ₄ and the like, a force oriented in the force (vertically downward with the magnetic force acting (magnetic attraction force) between the magnetic pole unit 50 and the magnetic member 53 ), The force pointing vertically upwards is
a, 82b are set to occur without current supply. In the following description, the above-described magnet bodies 80 ₁ ,
80 _2, 80 _3, 80 ₄ of the state metric of a predetermined value between each pole face and the plate-like magnetic material 85, it is assumed that appropriate called "steady state".

[0058] Also, the top of each permanent magnet 81, the gap sensor 86 _{1-86 4} for detecting the gap spacing between the flat-shaped magnetic member 85 is fixed, respectively. The gap interval information detected by the gap sensor is sent to main controller 20. Main controller 20 controls drive device 32 via stage control system 19 based on this gap interval information, and controls wafer stage WST. Drive control is performed in three degrees of freedom, Z, θ _X , and θ _Y.

In the wafer stage WST, as shown in FIGS. 5 and 3, a wafer support member 89 made of a magnetic shield material having a high magnetic permeability is fixed on a table 88. The wafer support member 89 is, as viewed in plan,
A central portion has a circular region larger than the wafer W, and has four legs extending in a cross shape from the circular region toward the outside. Then, the wafer support member 89
Are fixed to the center of the side of the table 88 at the ends of the four legs. Thereby, the contact area between the table 88 and the wafer support member 89 is minimized, and the armature unit 61 and the electromagnets 82a,
Conduction of heat generated by 82 b to wafer support member 89 via table 88 is suppressed. Therefore, the above-described armature unit 61 and the electromagnets 82a, 82
The heat generated by b is suppressed from being conducted to the wafer W suction-supported by a wafer support mechanism (not shown) such as a vacuum chuck or an electrostatic chuck in a circular region on the upper surface of the wafer support member 89.

Next, the principle of driving the wafer stage WST in the directions of six degrees of freedom by the wafer stage device 30 described above,
And position / posture control of wafer stage WST in directions of six degrees of freedom will be described.

[0061] First, X by the driving device 31, Y, θ 3 degrees of freedom of the driving principle and position and attitude control of the _Z will be described. It is assumed that wafer stage WST is in a stable floating support state.

In the magnetic pole unit 50, as shown by the solid arrow in FIG. 6A, the permanent magnet 52N generates a magnetic flux in the + Z direction (upward on the paper), and the permanent magnet 52S
A magnetic flux is generated in the Z direction (downward on the paper). The magnetic circuit is formed together with the magnetic member 53 and the magnetic member 68.

When the magnetic circuit shown in FIG. 6A is formed, the magnetic flux density B in the vicinity of the magnetic member 68, that is, at the Z position where the armature coil 63 is disposed, is as shown in FIG.
The distribution is as shown in FIG. That is, the permanent magnet 52
The absolute value of the magnetic flux density B becomes maximum at a position corresponding to the center point of N, 52S, and the absolute value of the magnetic flux density B becomes smaller from this point toward a position corresponding to the peripheral portion of the magnetic pole surface. The shape is such that good approximation is performed.
In FIG. 6B, when the direction of the magnetic flux is in the + Z direction, the value of the magnetic flux density B is positive, and when the direction of the line of magnetic force is in the −Z direction, the value of the magnetic flux density B is negative. FIG. 6 (B)
FIG. 6 shows the distribution of the magnetic flux density B in the X direction, but the distribution of the magnetic flux density B in the Y direction is the same as the distribution in FIG.

In this embodiment, stainless steel having high electric resistance, high saturation magnetic flux density, low magnetic hysteresis and low coercive force is used as the material of the magnetic member 68, so that eddy current and hysteresis loss are reduced. And the magnetic resistance can be kept low.
, The magnetic flux having a high magnetic flux density can be continuously generated.

When an electric current is supplied to the armature coil 63 in the environment of the magnetic flux density B having the distribution shown in FIG. 6B, a Lorentz electromagnetic force is generated in the armature coil 63. This Lorentz electromagnetic force moves the wafer stage WST and thus the wafer W. By the way, the magnitude and direction of the Lorentz electromagnetic force generated in the armature coil 63 are:
Depending on the magnitude and direction of the current supplied to the armature coil 63 and the positional relationship between the magnetic pole unit 50 and the armature unit 61, in the present embodiment, when moving the wafer stage WST in the X direction, According to the X position of the armature unit 61, a pair of two armature coils 63 adjacent in the X direction is selected, and each pair of the armature coils 63 is selected.
By supplying sinusoidal currents having the same amplitude and having phases different from each other by 90 ° according to the positional relationship between the magnetic pole unit 50 and the armature unit, the X component of the resultant force of the Lorentz electromagnetic force is converted to the X of the armature unit 61. Control is constant regardless of position. In addition, when a current is applied to drive the armature unit 61 in the X direction, generally, a force for driving the armature unit 61 in the Y direction and a rotational force around the Z axis are generated. Therefore, the current flowing through each armature coil 63 is adjusted so that the force for driving the armature unit 61 in the Y direction and the rotational force become zero as a whole. In addition, by controlling the amplitude and the direction of the sine wave current supplied to each armature coil, the magnitude and direction of the force for driving the armature unit 61 are controlled.

When the magnetic pole unit 50 moves in the Y direction, the magnetic pole unit 50 is driven in the Y direction in the same manner as in the X direction by a constant driving force regardless of the Y position of the magnetic pole unit 50. Driving.

A current is supplied to each armature coil 63 in a pattern in which the current pattern for driving the magnetic pole unit 50 in the X direction and the current pattern for driving in the Y direction are superposed at an appropriate ratio. As a result, the magnetic pole unit 50 can be driven in any direction along the XY plane with any driving force.
Is driving.

Further, by driving the magnetic pole unit 50 without canceling out the rotational force, the magnetic pole unit 50 is rotationally driven in a desired rotational direction and a desired rotational force.

As described above, in the exposure apparatus of this embodiment, the current supplied to the armature coil 63 is controlled according to the XY position and the attitude (rotation about the Z axis) θ _Z of the substrate table 18, The position of the wafer stage WST and thus the position of the wafer W are controlled.

In the wafer stage device 30 of the present embodiment, as described above, the mover 60 is attached to the wafer stage WST which holds the wafer W via the wafer support member 89. Therefore, main controller 20 monitors the measurement value (position information or velocity information) of wafer interferometer 35 and obtains XY of mover 60 and stator 50 at each time point obtained.
The stage control system 19 based on the relative positional relationship in the plane
By controlling the driving of the mover 60 as described above through the above, the wafer stage WST and the wafer W can be freely moved in the XY plane integrally therewith.

Next, the principle of driving the wafer stage WST in the directions of three degrees of freedom of Z, θ _X and θ _Y by the driving device 32 will be described.

[0072] magnet 80 _1, 80 _2, 80 _3, 80 ₄ are respectively, as representatively shown magnet body 80 ₁ in FIG. 7, the N pole surface 82N (FIG. 7 as a magnet body,
The magnetic pole surface of the electromagnet 82a facing the flat magnetic member 85)
Generates a magnetic flux in the + Z direction (upward on the paper surface), and in the −Z direction (downward on the paper surface) toward the S pole surface 82S (in FIG. 7, the magnetic pole surface facing the flat magnetic member 85 of the electromagnet 82b) as a magnet body. ) Is generated. At this time, the magnetic flux that has proceeded in the + Z direction from the N pole surface 82N reaches the plate-shaped magnetic member 85, then proceeds in the + X direction inside the plate-shaped magnetic member 85, and reaches the position facing the S pole surface 82S. Then, the light travels in the -Z direction toward the S pole surface 82S. In this way, the magnetic flux reaching the S pole surface travels through the magnetic member 83 of the electromagnet 82b, and passes through the S pole surface of the permanent magnet 81 to the permanent magnet 81.
In the -X direction. Then, after passing through the N-pole surface of the permanent magnet 81, it travels inside the magnetic member 83 of the electromagnet 82a and reaches the N-pole surface 82N. Thus, the electromagnet 82
a, a magnetic circuit sequentially passing through the plate-shaped magnetic member 85, the electromagnet 82b, and the permanent magnet 81 is formed. Note that the magnet body 80 _2, 80 _3, 80 ₄ as in the case the magnetic circuit for respectively a flat magnetic body 85 and magnetic body 80 ₁ and the plate-like magnetic material 85 also is formed.

When such a magnetic circuit is formed, the magnet body
80₁, 80_Two, 80_Three, 80_FourEach and flat magnetic body 8
5, a magnetic attractive force acts. Each magnet
The attraction force is the magnet 80₁, 80_Two, 80_Three, 80_FourIt
Each magnetomotive force and the magnet body 80 ₁, 80_Two, 80_Three, 80_FourSo
Between the respective N-pole and S-pole surfaces and the planar magnetic body 85
It depends on the gap interval.

[0074] Incidentally, the magnetomotive force of the magnet 80 _1, the magnetomotive force of the permanent magnet 81 constituting the magnet body 80 _1, the magnet body 8
0 ₁ is a sum of the magnetomotive force of the electromagnet 82a and the electromagnet 82b constituting the magnetomotive force of the electromagnet 82a, 82b varies depending on the direction and magnitude of the current supplied electromagnets 82a, to 82b. Here, if the direction of the current supplied to the electromagnets 82a and 82b is such that a magnetic flux in the same direction as the direction of the magnetic flux generated by the permanent magnet 81 is generated, the magnet body 80
The magnetomotive force of ₁ increases. On the other hand, the direction of the current supplied to the electromagnets 82a, 82b is, as long as the permanent magnet 81 is generated the direction and the magnetic flux in the opposite direction of the magnetic flux generated magnetomotive force of the magnet 80 ₁ is reduced. The amount of increase or decrease in the magnetomotive force can be changed by the current supplied to the electromagnets 82a and 82b. That is, the electromagnet 8
2a, by controlling the direction and magnitude of current supplied to 82b, it is possible to control the magnetic attractive force acting between the magnet body 80 ₁ and the plate-like magnetic material 85.

[0075] Also, the N pole surface and S-pole surface of the magnet body 80 _1, the gap spacing between the flat magnetic body 85, provided on the upper surface of the magnet body 80 _{1-80 4} each permanent magnet 81 four can be obtained from the detection result of the gap distance between the gap sensors 86 ₁ to 86 ₄ each gap by sensor 86 _{1-86 4} top a flat magnetic body 85 lower surface. In the present embodiment, since the N-pole surface and the S-pole surface of the magnet body 80 ₁ are arranged at short intervals, the wafer stage WST
If the theta ones rotation amount of the rotation amount and theta _Y direction of the _X-direction small, the N pole surface and S-pole surface of the magnet body 80 _1, the gap spacing between the flat magnetic body 85, Gyapusensa 86 ₁
Can be accurately obtained from only the detection result of In the present embodiment, the magnet body 80 ₁ of N pole face magnet body 80 ₁ of the S pole surface, and the upper surface of the gap sensor 86 ₁ is on a substantially same plane, the rotation amount of theta _X direction of the wafer stage WST And the rotation amount in the θ _Y direction is small, the gap interval GP detected by the gap sensor 86 _1
1, has an N-pole surface and the S-pole surface of the magnet body 80 _1, and the gap spacing between the flat magnetic body 85.

That is, based on the detection result of the gap interval GP ₁ by the gap sensor 86 ₁ , the electromagnet 82
a, by controlling the direction and magnitude of the current supplied to 82b, it is possible to control the magnetic attraction force of the magnitude between the magnet body 80 ₁ and the plate-like magnetic material 85.

[0077] In analogy to the control of the magnetic attraction force between the plate-shaped magnet 85 in the above magnet body 80 _1, the magnet body 8
0 _{2-80 4} can be controlled magnetic attractive force between each a flat magnetic body 85. That is, based on the detection result of the gap interval GP ₂ ~GP ₄ by the gap sensors 86 _{2-86 4,} to control the direction and magnitude of the current supplied to the magnet body 80 _{2-80 4} each electromagnet 82a, 82b it is thus possible to control the magnetic attraction force of the magnitude between the magnet body 80 _{2-80 4} respectively a flat magnetic body 85.

For this reason, the magnet body 80₁~ 80_Foureach
Direction and magnitude of current supplied to electromagnets 82a and 82b
By controlling the magnet body 80₁~ 80_FourWith each
To control the magnetic attractive force between the flat magnetic body 85
The magnet body 80₁~ 80_FourWafer stage provided with
WST is independently set at four points not on a straight line in the Z-axis direction.
Can be driven. Therefore, the driving device 32
Z, θ_X, Θ_YDrive in the three degrees of freedom
Can be. For example, in the steady state described above, the magnet body
80₁~ 80_FourIf the same current is supplied to all of the
Stage WST can be driven in the Z-axis direction. Ma
The magnet body 80₁, 80_FourSupply the same current to both
Magnet body 80_Two, 80_ThreeMagnet body 80 on both sides₁Electricity supplied to
If the same current different from the current is supplied, the wafer stage
WST to θ_XCan be driven in any direction. Furthermore, magnetic
Stone body 80₁, 80_TwoSupply the same current to both
80 _Three, 80_FourMagnet body 80 on both sides₁What is the current supplied to
If the same and different currents are supplied, wafer stage WST
To θ_YCan be driven in any direction.

Next, control of the position and orientation of wafer stage WST in three directions of freedom, Z, θ _X , and θ _Y by drive device 32 will be described.

The wafer stage WST is set at Z, θ _X and θ _Y.
In order to drive in the direction of freedom, it is sufficient to drive independently and arbitrarily in the Z-axis direction at three points that are not on a straight line on wafer stage WST, but in the present embodiment,
As described above, the points of action of the magnetic attraction force are four vertices of a square centered on the center of gravity of the drive target including the wafer stage WST in plan view. That is, as shown in the plan view of FIG. 8, points P ₁ to P ₁ apart from the center of gravity G of the drive target including the wafer stage WST by the distance D in the X-axis direction and the distance D in the Y-axis direction from the center of gravity G magnetic attraction force acts in the P _4. Therefore, in the present embodiment, the magnet body 8
0 ₃ and the magnet body 80 _4, consider replacing the virtual magnet body is present at the midpoint P ₅ between the point P ₃ and the point P _4, 3 degrees of freedom of the wafer stage WST Z, θ _X, θ _Y Drive in the direction.

At this time, the point P₁~ P_FivePlate magnetism in
Gap interval GP with body 85₁~ GP_FiveIs the center of gravity G
The distance in the Z direction from the flat magnetic body 85 is Z_G, The center of gravity G and each magnet
Stone body 80₁~ 80_FourPole face (gap sensor 86)₁~ 8
6_FourWith respect to the flat magnetic body 85) in the Z direction.
Z_PAnd θ of wafer stage WST_XThe amount of rotation in the direction
_XOf wafer stage WST_YThe amount of rotation in the direction_YDo
And GP₁= Z_G-Z_P−D (tan θ_X+ Tan θ_Y…… (1) GP_Two= Z_G-Z_P−D (−tanθ_X+ Tan θ_Y…… (2) GP_Three= Z_G-Z_P−D (tan θ_X−tanθ_Y…… (3) GP_Four= Z_G-Z_P−D (−tanθ_X−tanθ_Y…… (4) GP_Five= (GP_Three+ GP_Four) / 2 (5) Therefore, Z, θ of wafer stage WST_X, Θ_Y
Point P used for drive control in three degrees of freedom₁, P_Two,
P_FiveGap interval GP in₁, GP_Two, GP_FiveIs 86
₁~ 86_FourFour points P measured by₁~ P_FourGya in
Gap GP₁~ GP_FourFrom the unanimous decision
You. Note that, as is apparent from equations (1) to (5), the wafer
Position / posture (Z_G, Θ_X, Θ_Y)
Gap interval (GP₁, GP_Two, GP_Five) And one-to-one
are doing. Therefore, the gap interval (GP₁, GP_Two,
GP_Five) To control the wafer stage WST.
Position / posture (Z_G, Θ_X, Θ_Y) Can be controlled
You.

The gap intervals GP ₁ , GP ₂ , GP ₅
When the magnetic attraction forces FM ₁ , FM ₂ , FM ₅ to be generated at the points P ₁ , P ₂ , P ₅ are determined in order to obtain the target value, the magnet body disposed at the points P ₃ , P ₄ 80 _3, 80 _4, a magnetic attraction force FM _5/2 is to supply a current to act.

The object controlled by the drive unit 32 is the position / posture (Z _G , θ _X , θ) of the wafer stage WST.
A _Y) or gap spacing _{(GP 1, GP 2, GP} 5), the actual control amount is a voltage E ₁ to E ₄ supplied to each magnet 80 _{1-80 4.} A control system model in which the voltages E _{1 to} E ₄ are input and the gap intervals (GP ₁ , GP ₂ , GP ₅ ) are output is represented by an actual stage control system model 91 shown in FIG. In the control system model 91, when a voltage E ₁ to E ₄ are supplied to the magnet body 80 _{1-80 4,} the electric resistance model 93 determined by the electric resistance and inductance of the coil in the magnet body 80 _{1-80 4} respectively current I ₁ ~I ₄ the magnet body 80 _{1-80 4} flows according to. When the current I ₁ ~I ₄ is supplied to the magnet body 80 _{1-80 4,} the magnetic attractive force F ₁ to F ₄ is generated according to the magnetic force model 94 determined by the magnetic resistance. Wafer stage WST when these magnetic attraction force F ₁ to F ₄ is generated,
It moves according to the dynamics model 95 determined by the equation of motion, and the gap interval (GP
_1, GP _2, GP ₅₎ to become. The electric resistance model 93
The magnetic force model 94 forms an electromagnet model.

Here, both the electric resistance model 93 and the magnetic force model 94 have gap intervals (GP ₁ , GP ₂ , G
P ₅ ) as a non-linear parameter. Therefore, the actual control quantity E ₁ to E ₄ and gap spacing (GP _1,
GP ₂ , GP ₅ ) can be regarded as linear in a minute range, but generally have a non-linear relationship. Therefore, the control amount than the voltage E ₁ to E ₄ supplied to each magnet 80 _{1-80 4,} easy to control the gap distance over a wide control weight range _{(GP 1, GP 2, GP} 5) Cannot be controlled by linear control.

Therefore, in the present embodiment, a new control amount V (VZ, Vθ _X , Vθ _Y ) having a linear relationship with the gap intervals (GP ₁ , GP ₂ , GP ₅ ) is introduced, and the control amount V An additional element 92 for linking the voltage and the voltages E _{1 to} E ₄ is virtually arranged before the actual stage control system 91, thereby constructing a linear control system 90 as a whole. Such control amount V
(VZ, Vθ _X , Vθ _Y ) indicates the state of the wafer stage WST as P (Z _G , θ _X , θ _Y , dZ _G / dt, dθ _X / dt,
dθ _Y / dt) is defined as satisfying a linear state equation of dP / dt = A · P + B · V (6).
Here, A is the fourth to sixth components of state P (dZ _G / dt,
d? _X / dt, d? _Y / dt) is a matrix for extracting the first to third components, and B is a matrix for extracting the three components of the control amount V as the fourth to sixth components.

That is, the control amount V (VZ, Vθ _X , V
In theta _Y), a _{^{VZ = d 2 Z G / dt}} 2 ... (7) Vθ X = d 2 θ X / dt 2 ... (8) Vθ Y = d 2 θ Y / dt 2 ... (9), also , the controlled variable _{V (VZ, Vθ X, Vθ} Y) components of the magnetic attraction force acting on the magnet body 80 _{1-80 4} acts downwardly with respect to floating body comprising a wafer stage WST force (self-weight (Gravity and magnetic attraction between the stator) and the mass and moment of inertia of the levitation body. In addition,
In expressing the control amount V (VZ, Vθ _X , Vθ _Y ), it is convenient to use the above-described Z position in the steady state as the origin of the Z coordinate, and this is the case in the present embodiment.

In the additional element 92, the gap interval (G
P₁, GP_Two, GP_Five) And the force acting on the levitating body
According to the acceleration model 99, the gap interval (GP₁,
GP_Two, GP_Five) At the current value, given as the target value
Control amount V (VZ, Vθ_X, Vθ _Y) And needed to
Each magnet body 80 which becomes₁~ 80_FourMagnetic attraction F acting on₁~ F_Four
To determine. The magnetic attraction force F thus determined₁~ F_FourTo
Generated current I₁~ I_FourIs determined by the magnetic resistance
According to the magnetic force model 98, the gap interval (GP₁, G
P_Two, GP_Five) In consideration of the current value of
Current I₁~ I_FourE that generates₁~ E_FourThe magnet body
80₁~ 80_FourThe electrical resistance of the coil in each case and
To the electric resistance model 97 determined by the inductance value
Therefore, the output of the additional element 92 is obtained.

In the linear control model 90, the voltages E _{1 to} E ₄ which are the outputs of the additional elements are input to the actual stage control system model 91. Therefore, the linear control model 9
In the case of 0, since a kind of inversion operation for the electromagnet models (93, 94) that became a non-linear factor in the control system model 91 is performed in the magnetic force model 98 and the electric resistance model 97, the linear control model 90 is used as an input. Has a strictly linear relationship between the control amount V (VZ, Vθ _X , Vθ _Y ) and the gap interval (GP ₁ , GP ₂ , GP ₅ ) as an output.

[0089] Further, in the linear control system 90, the actual control amount is a magnet body 80 _{1-80 4} voltage is supplied to each E ₁ to E ₄ are appeared in the middle of the feedback control loop as a whole I have. That is, in the present embodiment,
The controlled variable _{V (VZ, Vθ X, Vθ} Y) adopted, output quantity (G
P ₁ , GP ₂ , and GP ₅ ) are strictly linearized to perform a control operation, and the voltages E _{1 to} E ₄ , which are actual control amounts obtained in the course of the control operation, are applied to the magnet body 8.
It is supplied to the 0 _{1-80 4.} Therefore, the output amount (GP
₁ , GP ₂ , GP ₅ ), that is, the position / posture (Z _G , θ _X , θ _Y ) of the wafer stage WST can be accurately controlled over a wide range.

In the above description, it is assumed that a voltage output power supply is used, and the actual control amounts are set to the voltages E _{1 to} E _4. However, when a current output power supply is used, the actual control amount is used. Can be the currents I _{1 to} I ₄ . In such cases,
The electric resistance models 93 and 97 in the control model of FIG. 9 become unnecessary.

[0091] As described above, according to wafer stage device 30 of the present embodiment, by using the drive device 31, the electromagnetic interaction, drive the wafer stage WST X, Y, the directions of three degrees of freedom theta _Z At the same time, the wafer stage WST is moved to Z,
theta _X, by driving the directions of three degrees of freedom theta _Y, thereby enabling driving the wafer stage WST 6 degrees of freedom directions.
As a result, the position and orientation of the stage can be controlled without any problem even in a non-air environment. Also, Z
No need for leveling tables, air bearings, etc.
The size and weight of the stage can be reduced, thereby improving the position controllability of the stage.

In the driving device 31, since the magnetic pole unit 50 is provided on the stator side, the magnetic pole unit 5 is provided near the armature unit 61 provided on the mover side.
Since the amount of the magnetic flux derived from 0 mixed into the magnetic circuit for generating the magnetic force in the drive device 32 can be increased, stable floating support is possible. Further, since the magnetic pole unit 50 is provided on the stator side, the magnetic flux generated by the magnetic pole unit 50 does not change with time, and a stable Lorentz force can be generated in a stable magnetic flux density distribution.

Further, since the magnetic member 68 is provided on the side of the armature unit 61 on the wafer stage WST side as a support member for the armature unit 61, the magnetic pole unit mixed into the magnetic circuit for generating a magnetic force in the driving device 32 50
Can reduce the amount of magnetic flux. Further, since a magnetic attraction force acts between the magnetic pole unit 50 and the magnetic member 68, the floating rigidity can be increased.

Since the heat generated in the armature coil 63 of the armature unit 61 is removed, the refrigerant is caused to flow through the space in which the armature coil 63 is housed.
To reduce the change in the driving force generation efficiency due to the temperature rise of the armature coil 63, the occurrence of thermal expansion due to the transfer of heat to members and devices surrounding the armature coil, and the occurrence of fluctuations in the atmosphere around the stage. Can be.

Further, since the armature coil 63 constituting the armature unit 61 is supported by the coil supporting member 65 which is supported separately from the wafer stage WST, the heat generated by the armature coil is efficiently removed. And the amount of heat generated by the armature coil to the stage can be reduced.

Further, the magnet body 80 constituting the driving device 32
_{1-80 4} respectively, electromagnets 82a, since it is configured by connecting a permanent magnet 81, and the electromagnet 82b in series, by adjusting the current supplied to the electromagnets, the magnet bodies 80
It is possible to adjust the magnetic force between the _{1-80 4} and the flat plate-like magnetic body 85, it is possible to reduce the amount of current supplied to the electromagnet.

Further, when the magnetomotive force of each permanent magnet 81 is such that current is not supplied to electromagnets 82a and 82b and the distance between flat magnet member 85 is a predetermined value, wafer stage WST and and force vertically downward acting on the entire moving portion that moves integrally with, since the sum of the magnetic attractive force is set so as to balance between the magnet body 80 _{1-80 4} and the flat plate-shaped magnetic member 85, Without adjusting the magnetic force, the stage can be held at the steady state position while the stage's own weight is supported by the magnetic force, and the adjustment of the position and orientation of the stage from the steady state can be realized with little energy. It becomes possible.

[0098] Further, based on a linear control model having nonlinear electromagnet model for the detection result of the gap interval GP ₁ ~GP ₄ magnet body 80 _{1-80 4} for supplying voltage (or current) and by the gap sensors 86 ₁ to 86 ₄ And the magnet body 8
0 _{1-80 4} because in the controlling the current supplied, accurately wafer stage WST wide range
(Z position) and attitude (θ _X , θ _Y ) can be controlled.

In the wafer stage WST, a wafer support member 89 made of a magnetic shield material having a high magnetic permeability is provided on the table 88, and the wafer W is held on the wafer support member 89. The amount of magnetic flux penetrating into the vicinity of the wafer W can be reduced.

Further, since the contact area between the wafer support member 89 and the wafer stage is minimized, the heat conducted from the driving devices 31 and 32 via the wafer stage table can be reduced.

As described above, wafer stage WST
That is, the flow of the exposure operation in exposure apparatus 100 of the present embodiment, which is performed while controlling the position of wafer W, will be briefly described.

First, a reticle R on which a pattern to be transferred is formed is loaded on a reticle stage RST by a reticle loader (not shown). Similarly, the wafer W to be exposed is set on the substrate table 11 by a wafer loader (not shown).
Is loaded.

At this time, wafer stage WST is floated and supported in a base shape at a predetermined wafer loading position, and is controlled by main controller 20 to maintain a stopped state at the loading position for a predetermined time. Servo control is performed via the system 19. Therefore, during the waiting period in the loading position, current is supplied to the armature coil 63 of the driving device 31 and the electromagnets 82a and 82b of the driving device 32.
Further, in order to prevent the temperature rise due to the heat generated in the armature coil 63 and the propagation of heat to the surroundings, the main controller 20 cools the armature coil 63 using the cooler 18 and the like.

Next, after the main controller 20 performs preparatory operations such as reticle alignment and baseline measurement using a reticle microscope (not shown) and an alignment detection system (not shown) in accordance with predetermined procedures, the alignment detection system EGA performed using statistical methods
An alignment measurement such as (enhanced global alignment) is performed. The details of the EGA measurement are described in, for example, JP-A-61-44429.

After the completion of the alignment measurement, the exposure operation of the step-and-scan method is performed as follows.

In this exposure operation, first, the wafer W
The substrate table 11 is moved so that the XY position of the substrate table becomes the scanning start position for exposing the first shot area (first shot) on the wafer W. This move
This is performed by controlling the current of each armature coil 63 constituting the drive unit 31 by the main control unit 20 via the stage control system 19 as described above. Also, the desired Z
The driving device 32 is controlled so that the position and orientation (θ _X , θ _Y ) are obtained.
Are supplied to the electromagnets 82a and 82b constituting
At the same time, reticle stage RST is moved such that the XY position of reticle R becomes the scanning start position. This movement is performed by the main controller 20 via the stage control system 19.

Then, the stage control system 19 controls the XY position information of the reticle R measured by the reticle interferometer 16 and the X-axis information of the wafer W measured by the wafer interferometer 35.
Based on the Y position information, the reticle R and the wafer W are synchronously moved via a reticle driving unit and a driving device 31 (not shown). During the synchronous movement, the reticle R is illuminated by a rectangular (slit-shaped) illumination area IAR having a longitudinal direction in a direction perpendicular to the scanning direction of the reticle R,
The reticle R is scanned (scanned) at a speed V _R at the time of exposure. An illumination area IAR (the center substantially coincides with the optical axis AX) is projected onto the wafer W via the projection optical system PL and is conjugate to the illumination area IAR. A slit-shaped projection area, that is, an exposure area IA is formed. Then, the wafer W is scanned at a speed V _W in synchronization with the reticle R, the entire surface of the shot area on the wafer W can be exposed. The scanning speed ratio V _W / V _R accurately corresponds to the reduction magnification of the projection optical system PL, and the pattern of the pattern area of the reticle R is accurately reduced and transferred onto the shot area on the wafer W. Is done.

[0108] The detection result by the multi-point focus position detection system previously described, not shown in the synchronous movement of the reticle R and the wafer W, and on the basis of the detection result of the gap sensor 86 _{1-86 4,} on the wafer W Driving control of the wafer stage WST in three degrees of freedom of Z, θ _X , and θ _{Y so that} the exposure area IA coincides with the image forming plane of the projection optical system PL is performed by the stage control system 19 via the driving device 32.

When the transfer of the reticle pattern to one shot area is completed by the scanning exposure performed while being controlled as described above, the wafer stage WST is stepped, and the scanning exposure is performed to the next shot area. In this way, the stepping and the scanning exposure are sequentially repeated, and the required number of shot patterns are transferred onto the wafer W. In such scanning exposure, a reaction force is generated on the base 47 with the movement of the wafer stage WST to induce vibration.
The vibration is not transmitted to the projection optical system PL and the like because it is completely separated from the main body column 41 and the like supporting the L.

As described above, according to the exposure apparatus 100 of the present embodiment, high-speed movement and high-precision position control of the wafer W can be performed, so that both throughput and exposure accuracy can be improved.

The apparatus 100 of the present embodiment assembles a reticle stage RST including a number of mechanical parts, a projection optical system PL including a plurality of lenses, a wafer stage apparatus 30 having the above-described configuration, and the like. Then, after combining the reticle stage RST, the projection optical system PL, the wafer stage device 30, and the like, comprehensive adjustment (electric adjustment,
Optical adjustment, operation confirmation, etc.). It is desirable that the exposure apparatus 100 be manufactured in a clean room in which temperature, cleanliness, and the like are controlled.

In the above embodiment, the stator side of the driving device 31 constituting the wafer stage apparatus 30 is completely separated from the other exposure apparatus 100, but as shown in FIG. Alternatively, the stator 50 of the driving device 31 can be attached to the leg 45 via a vibration isolator 59.

In the magnetic pole unit of the flat motor 31, an electromagnet equivalent to a permanent magnet can be used instead of a permanent magnet. Further, the shape and the arrangement cycle of the permanent magnets and the armature coils in the planar motor 31 are not limited to the above-described embodiment, but may be in accordance with the driving method to be adopted. Further, in the above embodiment, the magnetic member is used as the holding member of the armature coil. However, a non-magnetic member may be used.

Further, in the above embodiment, the cooling liquid is used for cooling the armature coil, but a gaseous refrigerant can be used as long as it is a fluid serving as a refrigerant.

In the above-described embodiment, the plane motor 31 has the armature unit provided with the armature unit and the stator has the magnetic pole unit. However, the mover has the magnetic pole unit, and the stator has the armature unit. May be provided.

In the above-described embodiment, the whole wafer supporting member is made of the magnetic shield material. However, a low magnetic permeability member may be used as the base material of the wafer supporting member, and the magnetic shielding material may be attached to the wafer side surface. Good.

In each of the above embodiments, the present invention employs Ar
Although the description has been given of the case where the present invention is applied to the F exposure apparatus, the scope of the present invention is not limited to this, and vacuum ultraviolet light such as F ₂ laser light (wavelength: 157 nm) is used as the exposure illumination light. VUV exposure equipment, wavelength 5-15n
m as well as an EUV exposure apparatus that uses exposure light as exposure light.
The present invention is also applicable to an exposure apparatus using a charged particle beam, such as a line exposure apparatus, an electron beam exposure apparatus, and an ion beam exposure apparatus. In addition, it goes without saying that the present invention may be suitably applied to a DUV exposure apparatus using a KrF excimer laser beam, g-line or i-line as exposure illumination light, even if the inside of the chamber may be an air atmosphere. Further, the present invention is not limited to a step-and-repeat machine, a step-and-scan machine, and a step-and-stitch machine.

The motor device of the present invention is not limited to application to a substrate stage device in an exposure apparatus, but can be applied to, for example, a reticle stage device in an exposure apparatus. However, the method can be applied when position control of the sample is required.

[0119]

As described above, according to the stage apparatus of the present invention, the driving is performed by the electromagnetic force in the three degrees of freedom in the moving plane, and the magnetic is driven in the remaining three degrees of freedom. Even in a non-air environment, there is an effect that the position and orientation of the stage can be controlled without any trouble, and the configuration of the stage can be simplified and the size and weight can be reduced.

Further, according to the exposure apparatus of the present invention, by using the stage apparatus of the present invention, the structure of the stage can be simplified, and the size and weight can be reduced. Acceleration can be achieved, and the throughput can be improved by shortening the positioning settling time and the like.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of an exposure apparatus according to an embodiment.

FIGS. 2A and 2B are diagrams showing the configuration of a base and a stator of FIG. 1;

FIG. 3 is a longitudinal sectional view showing a configuration around a mover of FIG. 1;

FIG. 4 is a view showing an arrangement and a shape of an armature coil in the mover shown in FIG. 3;

FIG. 5 is a perspective view showing a configuration around a wafer table.

FIGS. 6A and 6B are diagrams for explaining a magnetic circuit using the stator of FIG. 2;

FIG. 7 is a diagram for explaining a magnetic circuit using a magnet body.

FIG. 8 is a view for explaining an arrangement position of a magnet body on a wafer stage.

FIG. 9 is a diagram for explaining a levitation control system.

FIG. 10 is a diagram for explaining a modified example.

[Explanation of symbols]

18: cooling device, 19: stage control system (part of current control device), 20: main control device (part of current control device),
Reference numeral 30: wafer stage device (stage device), 31: drive device (first drive device), 32: drive device (second drive device), 50: stator (magnetic pole unit), 59: anti-vibration device (anti force cancellation mechanism), 60 ... movable member 61: an armature unit, 63 ... armature coil, 65 ... coil support member, 80 _{1-80 4} ... magnet body (part of the adjustment device), 81
... permanent magnets, 82a, 82b ... electromagnets, 85 ... plate-shaped magnetic material, 88 ... table, 89 ... wafer support member (object support member), W ... wafer (object, substrate), PL ... projection optical system (optical system) .

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H01L 21/30 515G F-term (Reference) 2H097 AA03 AB09 CA13 GB01 KA03 KA29 LA10 LA12 5F031 CA02 CA05 KA06 KA07 KA08 LA04 LA08 MA27 NA04 NA05 PA09 5F046 CC01 CC03 CC05 CC06 CC17 5H641 BB06 BB15 BB16 BB18 GG03 GG05 GG07 GG11 GG12 GG26 GG29 HH02 HH06 JA07 JB04 JB05

Claims (19)

[Claims] 1. A stage having a mounting surface on which an object is mounted; a first driving device for driving the stage by an electromagnetic force along a moving surface; and an adjustment disposed on the stage to adjust a magnetic force. And a second driving device for driving the stage with a magnetic force in a direction intersecting the moving surface. 2. The first driving device comprises: a mover provided on the stage so as to face the moving surface; and a stator driving the stage by electromagnetic interaction between the mover and the mover. The stage device according to claim 1, further comprising: 3. The stage apparatus according to claim 2, wherein the mover has an armature unit, and the stator has a magnetic pole unit. 4. A container member in which a storage space for storing the armature unit is formed; and a cooling device that supplies a refrigerant to the storage space to cool each of the armature coils. The stage device according to claim 3. 5. The armature unit according to claim 4, wherein the armature unit includes a plurality of armature coils, and further includes a coil support member that supports the plurality of armature coils apart from the stage. Stage equipment. 6. The adjusting device has at least three magnets disposed on the mounting surface side of the stage and having a magnetic pole surface substantially parallel to the mounting surface, wherein the second driving device includes: A magnetic body comprising a flat plate-shaped magnetic member facing a magnetic pole surface of the magnet body.
6. The stage device according to any one of items 5. 7. The apparatus according to claim 6, wherein the stage has a quadrangular shape, and one of the magnet bodies is arranged at each of the four corners on the mounting surface side of the stage.
A stage device according to item 1. 8. The stage device according to claim 6, wherein the magnet body includes an electromagnet. 9. The stage apparatus according to claim 8, wherein the magnet body further includes a permanent magnet that forms a magnetic circuit with the electromagnet. 10. The stage according to claim 7, wherein the current is not supplied to the electromagnet and an interval between each of the magnets and the flat magnetic member is a predetermined value. The magnetic force is set such that the vertical force acting on the whole of the magnet and the magnet body and the total magnetic force between the magnet body and the plate-shaped magnetic member are balanced. The stage device according to claim 9. 11. The adjusting device, comprising: at least three gap sensors provided on the mounting surface side of the stage to detect a gap amount between the adjusting device and the flat magnetic member; and based on a detection result by the gap sensor. 11. The stage device according to claim 8, further comprising: a current control device configured to control a current supplied to the electromagnet. 12. The current control device controls a current supplied to the electromagnet based on a linear control model having a non-linear electromagnet model related to a current supplied to the electromagnet and a detection result of the gap sensor. The stage device according to claim 11, wherein: 13. The stage according to claim 1, wherein the stage includes: a table that moves along the moving surface; and an object supporting member provided on the table and supporting the object. The stage device according to claim 1. 14. The object supporting member according to claim 1, wherein the object supporting member is made of a magnetic shield material having a high magnetic permeability.
4. The stage device according to 3. 15. The stage according to claim 13, wherein the stage further comprises a magnetic shield member made of a magnetic shield material having a high magnetic permeability attached to the object-side surface of the object support member. Stage equipment. 16. The stage apparatus according to claim 13, wherein the object support member is supported on the table at at least three places. 17. An exposure apparatus for exposing a substrate by an energy beam via an optical system and transferring a predetermined pattern to the substrate, comprising: the stage device according to claim 1. Description: An exposure apparatus, comprising: the stage constituting the stage device as a substrate stage for holding the substrate. 18. The first device constituting the stage device
18. The exposure apparatus according to claim 17, wherein the driving device and the holding unit that holds the optical system are independent with respect to vibration. 19. The first device constituting the stage device
18. The exposure apparatus according to claim 17, further comprising a reaction force canceling mechanism for canceling a reaction force generated by driving the substrate stage by the driving device.