JPH10246228A - Static pressure gas bearing and stage device using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a stage constituting member from being distorted by constituting a guide body having a guide face and a moving body having a face to be guided jetting gas to the guide face out of dielectric, and providing an electrostatic attractive force generating means between the guide face and the face to be guided. SOLUTION: An electrode 32 is on the whole face of the guide face 104a of a X-guide bar 104 formed out of dielectric, and electrodes 34a, 34b are on the gas jetting part 102 to be the face to be guided of a moving body 30, formed by vapor deposition and the like. The gas jetting part 102 is formed with a rectangular frame-shaped groove 36, gas jetting holes 38 are provided on the positions in the vicinity of the middle points of the respective sides, the electrodes 34a, 34b are connected to one polarity side of a power source 40, and the electrode 32 is connected to the other polarity side, respectively. The guide face 104a and the face to be guided are opposed to each other, and when fixed voltage is impressed from the power source 40, electrostatic attractive force is generated between both faces. Because the electrodes 34a, 34b are on the same face as the gas jetting part 102, the electrostatic attractive force is generated in the same face as the repulsion by pressure of static pressure gas by the gas jetting part 102. Consequently, even if a plurality of the moving bodies 30 are leaded on a Y guide bar carrying body, distortion or deformation is not generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrostatic gas bearing and a stage apparatus using the same, and for example, relates to a hydrostatic gas bearing suitable for an exposure apparatus and the like, and a stage apparatus using the same.

[0002]

2. Description of the Related Art An exposure substrate, a workpiece, and an object to be measured are mounted on an exposure apparatus used in a photolithography process in the manufacture of a semiconductor device or a liquid crystal display device, as well as on a precision machine tool or a three-dimensional measuring machine. Then, a stage device for moving at high speed and high precision in a two-dimensional plane is used. In these stage devices, a moving body fixed to a carrier of the stage moves while being guided by a guide body (guide bar). The guide surface of the guide body and the guided surface of the movable body are opposed to each other at a predetermined interval by, for example, a static pressure gas bearing.

[0003] The static pressure gas bearing generates a force in the direction of increasing the distance between the guide body and the moving body by the pressure of the static pressure gas. In order to constitute the stage device, the distance between the guide and the moving body needs to be kept constant. Therefore, it is necessary to apply a force in a direction to reduce the distance between the guide and the moving body in order to balance the force. This force is called the preload of the hydrostatic gas bearing.

Conventionally, the following three types of methods have been used to apply a preload. (1) A rectangular guide body is surrounded by a U-shaped or square-shaped movable body, and a static pressure gas bearing is provided on the movable body so as to oppose both surfaces of the guide body, and the guide body by the pressure of the static pressure gas is provided. And the repulsive force of the moving object.

(2) A vacuum pocket is provided in the vicinity of the static pressure gas bearing provided on the moving body to generate a suction force between the moving body and the guide, thereby balancing the repulsion force of the static pressure air. FIG. 5A shows a hydrostatic gas bearing according to this method. FIG. 5A shows only the moving body 50 side, and the illustration of the opposing guide body is omitted. A static pressure gas bearing 52 is provided on the guided surface of the moving body 50.
, And a preload vacuum section 54 is provided on both sides thereof. The static pressure gas bearing 52 has a rectangular frame-shaped groove 50 a formed therein, and the groove 50 a.
Gas vent holes 50b are provided at four places near the midpoint of each side of the rectangular frame a.
Is provided. The preloading vacuum section 54 has a vacuum pocket 54a having a rectangular opening surface and a concave portion formed therein, and a vacuum suction hole 54b for sucking gas is provided at a substantially central portion thereof. Then, in a state in which the guide surface of the guide body and the guided surface of the moving body 50 face each other, a gas is blown out from the gas blowing holes 52b to generate a force in a direction to widen the gap between the guide body and the moving body, and vacuum suction is performed. A predetermined space is provided between the guide body and the moving body 50 by generating a predetermined suction force between the guide body and the moving body 50 by sucking the gas from the hole 54b.

(3) The guide body is made of a magnetic material, and a magnet is provided near the static pressure gas bearing provided on the moving body to generate an attractive force between the guide body and the repulsive force of the static air. Balance. FIG. 5B shows a hydrostatic gas bearing according to this method. FIG. 5B also shows only the moving body 50 side, and the illustration of the opposing guide body is omitted. The same static pressure gas bearing 52 as that shown in FIG. 5A is provided on the guided surface of the moving body 50, and preload magnets 56 are provided on both sides thereof. Then, in a state where the guide surface of the guide body and the guided surface of the moving body 50 face each other, a gas is ejected from the gas ejection holes 52b to generate a force in a direction to widen the gap between the guide body and the moving body, and a preloading force is generated. By generating a predetermined attractive force between the guide body and the moving body 50 by the magnetic force of the magnet 56, a predetermined space is provided between the guide body and the moving body 50.

[0007]

However, the above 3)
The types of methods have the following problems. (1) In the method in which the hydrostatic gas bearing is opposed to both surfaces of the guide body, the number of components increases, so that it is difficult to reduce the size of the moving body.
In addition, it is necessary to process and assemble a plurality of parts with high precision, resulting in an increase in cost.

(2) In the method of generating the attraction force of the magnet, the guide is limited to a magnetic material. Generally, steel is used. Even if the steel is slightly scratched, swelling called burrs may occur around the scratch, or rust may be generated from the scratched portion.

(3) Since the method of using the suction force of the vacuum pocket is not limited to the material of the guide body, stones and ceramics that are free from burrs and rust can be used. However, the force generated in the vacuum pocket is 1 kg per 1 cm ²
Since f is the upper limit, when a large suction force is required, the moving body becomes large.

Another problem common to all of the above-described conventional systems is that the point of action of the repulsive force due to the pressure of the static air and the attraction force generated by each system is different, so that the transfer body supporting the moving body is distorted. This causes a problem that the performance of the static pressure gas bearing, such as rigidity and damping property, may be deteriorated.

An object of the present invention is to provide a small and inexpensive hydrostatic gas bearing which does not cause distortion in a stage component supporting a moving body. It is another object of the present invention to provide a stage device in which a component supporting a moving body is not deformed by pressure of static air or the like.

[0012]

The object of the present invention will be described with reference to FIGS. 2 to 4 showing an embodiment. The above object is to provide a guide member (10) having a guide surface (104a) and made of a dielectric material.
4) and blowing out gas to the guide surface (104) to guide the surface (1).
A gas ejecting portion (102) for generating a repulsive force is provided between the guide surface (04a) and the guided surface facing the guide surface (104a). Means for generating an electrostatic attraction force (3)
2, 34, 40).

In the above static pressure gas bearing, the electrostatic attraction force generating means includes electrodes (34, 32) formed on the guide surface (104a) and the guided surface, and the electrodes (34, 32).
A voltage applying means (40) for applying a predetermined voltage therebetween. In the static pressure gas bearing, the electrostatic attraction force generating means includes a plurality of electrodes (34c to 34f, 32a, 32b) formed on one of the guide surface (104a) and the guided surface, and a plurality of electrodes. And a voltage applying means (40) for applying a predetermined voltage between the electrodes.

[0014] In the above-mentioned hydrostatic gas bearing, the gas ejection portion (102) is formed in the guided surface, and the guide surface (1) is formed.
04a) has a plurality of gas ejection holes (38) for ejecting gas.

It is another object of the present invention to provide a stage device having a stage fixed to a moving body (30) and movable in a guiding direction of a guiding body (104), and provided with the above-mentioned hydrostatic gas bearing. Achieved by the featured stage apparatus.

According to the present invention, both the moving body and the guide are made of a dielectric material, and the electrodes are formed on the bearing surface of the hydrostatic gas bearing of the moving body and / or the guide surface of the guide by vapor deposition or the like. By applying a voltage, a suction force is generated between the guide body and the moving body to balance with the repulsive force of the static pressure gas. A dielectric can be used as the material of the body.

Further, since there is no need to provide a preload magnet or a vacuum pocket beside the gas ejection portion, the size of the apparatus can be reduced. In addition, since the generated electrostatic attraction force can be generated on the same surface as the repulsive force due to the pressure of the static pressure gas, distortion or deformation does not occur in the components supporting the moving body of the static pressure gas bearing. You can do so. Therefore, it is possible to realize a stage device in which distortion or deformation does not occur in the support member or the like of the static pressure gas bearing.

[0018]

1 to 4 show a hydrostatic gas bearing and a stage device using the same according to an embodiment of the present invention.
This will be described with reference to FIG. First, an outline of the overall configuration of a stage device equipped with the hydrostatic gas bearing according to the present embodiment will be described with reference to FIG. The stage device according to the present embodiment is mounted on an exposure device used when manufacturing a semiconductor device or the like, and is a stage device (hereinafter, referred to as a wafer) on which an exposure substrate (hereinafter, referred to as a wafer) can be mounted and two-dimensionally moved. Wafer stage).

FIG. 1 is a partially cutaway perspective view for explaining the structure of the wafer stage.
A wafer 20 is held by vacuum suction on a wafer holder (not shown) on the sample stage 5 via a stage and a Y stage. A pattern on a reticle (not shown) is irradiated with illumination light for exposure, and an image of the pattern is transferred and exposed on the wafer 20. Hereinafter, the X axis and the Y axis are plotted on a plane parallel to the surface plate 1.
A description will be given by taking a rectangular coordinate system composed of axes and taking the Z axis perpendicular to the rectangular coordinate system.

The stators 3A and 4A of the linear motors 3 and 4 for driving the X stage are fixed in the vicinity of both ends in the Y direction on the surface plate 1 in parallel with each other along the X direction. I have. Further, an X guide bar (guide body) provided with a guide surface for the X stage along the inner side surface (the surface in the −Y direction) of the stator 3A fixed near the end in the + Y direction of the surface plate 1. 104 is fixed. A movable element 3B of the linear motor 3 is provided on the stator 3A, and a movable element 4B of the linear motor 4 is provided on the stator 4A. The mover 3B is fixed to the upper end in the + Y direction of a Y guide bar (guide) 112 serving as a guide surface of the Y stage via a fixing frame 6 that straddles the X guide bar 104, and the other mover 4A. Is fixed to the upper end of the Y guide bar 112 in the −Y direction via the fixing frame 7.

Both ends of the Y guide bar 112 in the Y direction are +
A first Y guide bar transporter 101 disposed in the Y direction,
And the second Y guide bar transport body 1 disposed in the -Y direction
05. First Y guide bar carrier 10
The bottom surface and the outer surface (the surface in the + Y direction) of the first Y guide bar carrier 105 face the upper surface of the surface plate 1 and the guide surface of the X guide bar 104, respectively. Are facing each other. The X stage is composed of the X guide bar 104, the Y guide bar 112, the Y guide bar transporters 101 and 105, and the like. The X stage moves in the X direction in the same manner as the movers 3B and 4B of the X-axis linear motors 3 and 4, respectively.

The X guide bar (guide) 104 and the Y guide bar transporter 101 are formed of a dielectric material. The Y guide bar transport body 101 has a plurality of moving bodies 30 each having a gas ejection unit 102 and formed of a dielectric.
In the present embodiment, a hydrostatic gas bearing is constituted by the moving body 30 and a guide body (here, the X guide bar 104) for guiding the moving body 30.

The gas ejection section 102 of the moving body 30 is provided on the surface (guided surface) of the Y guide bar transport body 101 facing the X guide bar 104. As will be described later in detail with reference to the drawings, the gas ejection portion 102 of the moving body 30 has pores formed therein, through which air is blown. FIG. 1 shows three gas ejection units 102 among the plurality of gas ejection units 102.

Although not shown and described in detail in FIG. 1, a repulsive force due to air pressure generated in the gas ejection portion 102 and an electrostatic attraction force generating means which is a component of the hydrostatic gas bearing according to the present embodiment. (To be described in detail later), the balance between the electrostatic attraction force generated between the guide surface of the X guide bar 104 and the guided surface of the Y guide bar transport body 101,
The Y guide bar transport body 101 is restrained by the X guide bar 104 while maintaining a constant interval.

The surface plate 1 of the Y guide bar carrier 101
A similar static pressure gas bearing is also provided on the surface facing
The Y guide bar transport body 101 is restrained on the surface plate 1 while maintaining a constant gap. Further, a similar hydrostatic bearing is provided on a surface of the Y guide bar transport body 105 facing the surface plate 1, and the Y guide bar transport body 105 is restrained by the surface plate 1 while maintaining a constant gap. .

Further, Y guide bar transport bodies 101 and 105
Each of the two ends has two Y-axis linear motors (one linear motor 8 in FIG. 1) for driving the X-direction bearings 111A and 111B on which the sample stage 5 is mounted.
A is shown. The stators 15A and 15C of the other linear motor (only the stator is shown) are fixed in parallel with each other. Stator 15A of linear motor 8A
Is provided with a mover 15B, and another linear motor is also provided with a similar mover. The two movers (the mover 15B and the like) each have an X-direction bearing body 111.
A, 111B are directly fixed to the side surfaces. In addition, the two X-direction bearing bodies 111A and 111B are fixed on the bottom surface side thereof to a vertical support member 106 disposed opposite to the bottom surface side of the Y guide bar 112. The bottom surface of the vertical support 106 faces the upper surface of the surface plate 1. The above-described vertical support 106 and X-direction bearing 111
A, 111B, the sample stage 5 and the like constitute a Y stage. The Y stage moves in the Y direction along the Y guide bar 112 in the same manner as the mover 15B of the two Y-axis linear motors.

A plurality of gas ejection portions and a static pressure gas bearing provided with an electrostatic attraction force generating means are provided on a surface of the vertical support body 106 facing the surface plate 1 so as to support the vertical support. The body 106 is restrained on the surface plate 1 while keeping a certain gap.
Further, only a plurality of gas ejection portions of the hydrostatic gas bearing are provided on the respective surfaces of the X-direction bearing members 111A and 111B facing the Y guide bar 112. The X-direction bearing members 111A and 111B maintain a certain gap between the X-direction bearing members 111A and 111B and the Y guide bar 112 by the repulsive force of the air pressure.
A sufficiently large gap is provided between the vertical support 106 and the Y guide bar 112 and between the sample table 5 and the Y guide bar 112.

Further, a laser interferometer 16 for measuring the X coordinate and a laser interferometer for measuring the Y coordinate fixed on the surface plate 1 are provided at the respective ends of the sample table 5 in the −X direction and the + Y direction. A moving mirror 18 and a moving mirror 19 that reflect laser beams 16A and 17A emitted from 17 are fixed,
The X and Y coordinates of the sample table 5 are detected by these laser interferometers 16A and 17A. Although not shown in the stage apparatus of the present embodiment, the moving mirrors 18 and 19 and the wafer 20 are integrally moved in a vertical direction (Z direction), and are rotated around X, Y and Z axes. Is installed. Further, a temperature sensor 21 for measuring a temperature near an optical path of the laser beam 16A is provided near the laser beam 16A of the laser interferometer. The measured value of the temperature sensor 21 is supplied to an air conditioning system (not shown). That is, the stage device of this embodiment is particularly suitable for the laser interference systems 16 and 1.
In order to keep the temperature of the optical path of the laser beams 16A and 17A at a constant level, the entire stage is under an air-conditioned environment, and as shown by an environmental airflow 23, the air for overall air-conditioning is provided by the laser interferometer 16 for X coordinate measurement. It is swept toward the stage from behind.

Next, the hydrostatic gas bearing according to the present embodiment mounted on the wafer stage shown in FIG. 1 will be described with reference to FIGS. FIG. 2 is a perspective view showing the hydrostatic gas bearing according to the present embodiment. FIG. 2A is a perspective view of the X guide bar 104 (guide body) in FIG. 1 from a position where the guide surface side can be observed.
2B is a perspective view of the moving body 30 from a position where the gas ejection unit 102 provided on the guided surface of the Y guide bar transport body 101 in FIG. 1 can be observed. In FIG. 2A,
Guide surface 104 of X guide bar 104 formed of dielectric
An electrode 32 made of metal or the like is formed on the entire surface by vapor deposition or the like. On the other hand, as shown in FIG.
An electrode 34 made of metal or the like is also formed on the gas ejection portion 102 serving as a guided surface of the above by vapor deposition or the like.

A rectangular frame-shaped groove 36 is formed in the gas ejection portion 102, and gas ejection holes 38 are provided at four locations near the midpoint of each side of the rectangular frame of the groove 36. The electrode 34 is divided into two parts, an electrode 34a in an area outside the rectangular frame-shaped groove 36 and an electrode 34b in an area inside the groove 36. These electrodes 34a and 34b are electrically connected to one polarity side of the power supply 40, and are connected to the electrode 3 of the X guide bar 104.
2 is connected to the other polarity side of the power supply 40. When a predetermined voltage is applied from the power supply 40 with the guide surface of the X guide bar 104 having such a configuration facing the guided surface of the moving body 30, an electrostatic attractive force is applied between the guide surface and the guided surface. Occurs.

The electrostatic attraction generating means described with reference to FIG. 1 has the above-described electrodes 32 and 34 and a power supply 40 as main components. An electrostatic attraction force generating means of a type in which electrodes are formed on both the moving body 30 and the guide body 104 and a voltage is applied between both electrodes as shown in FIG. 2 will be referred to as a monopolar electrostatic attraction body. I do. The attraction force generated by the single-pole type electrostatic attraction body will be described below. The electrode area is S
(M ² ), the dielectric constant of vacuum is εo, and the dielectric constant of air is ε
Assuming that r, the applied voltage is V, and the distance between the electrodes is d, the electrostatic attractive force F is expressed by the following equation.

F = (S / 2) · εo · εr · (V / d) ^1/2

Εo = 8.85 × 10 ^-12 (C ² N
⁻¹ m ⁻² ) and εr = 1, the electrode spacing corresponds to the bearing gap of the hydrostatic gas bearing, so if d = 5 μm and the applied voltage V = 150 V, the suction force per cm ² is about It becomes 4 kgf, and it is possible to generate a force four times or more the vacuum suction. According to this single-pole type electrostatic attraction member, it is possible to easily generate a large electrostatic attraction force by increasing the voltage.

Further, since the electrode 34 on the moving body 30 side is formed on the same plane as the gas ejection section 102, the moving body 30
The electrostatic attractive force generated between the electrode 34 on the side and the electrode 32 of the X guide bar 104 is generated on the same plane as the repulsive force of the gas ejection unit 102 due to the pressure of the static gas. Therefore, for example, the Y guide bar conveyance body 101 in FIG.
Even if a plurality of moving bodies 30 shown in (b) are mounted, no force that causes distortion or deformation of the Y guide bar conveyance body 101 is generated.

Next, another configuration of the hydrostatic gas bearing according to the present embodiment will be described with reference to FIGS. The static pressure gas bearing shown in FIGS. 3 and 4 shows a bipolar electrostatic attraction body in which a plurality of electrodes are provided on one of the moving body and the guide body to apply a voltage. FIGS. 3A and 4A are perspective views of the X guide bar 104 (guide body) in FIG. 1 from a position where the guide surface side can be observed.
4B and 4B are perspective views of the moving body 30 from a position where the gas ejection section 102 provided on the guided surface of the Y guide bar transport body 101 in FIG. 1 can be observed.

First, an example of a hydrostatic gas bearing using a bipolar electrostatic attracting body according to the present embodiment will be described with reference to FIG. FIG.
In (a), no electrode is formed on the guide surface of the X guide bar 104, which is a guide, and there is no difference from a conventional guide except that the material is a dielectric.
On the other hand, in FIG. 3B, the gas ejection portion 102 serving as a guided surface of the moving body 30 which is a dielectric is formed with four divided electrodes 34c to 34f. Electrodes 34c-
The electrode region in which the 34 f is formed is a region inside and outside the rectangular frame-shaped groove 36 of the gas ejection portion 102 and the gas ejection portion 10.
2 in the right and left direction (the moving direction of the moving body 30 and is indicated by an arrow in the figure). Electrode 3 on the outside
4c, the inside of the groove 36 is the electrode 34d, and the gas ejection portion 10
The electrode 34e is on the left side of 2 and the outside of the groove 36 is an electrode 34f, and the electrode 34f is on the inside of the groove 36. Then, the electrodes 34c and 34d are electrically connected and connected to one polarity side of the power supply 40,
The electrodes 34 e and 34 f are electrically connected and connected to the other polarity side of the power supply 40.

A predetermined voltage is applied between the electrodes 34c and 34d and the electrodes 34e and 34f from the power source 40 with the guide surface 104a of the X guide bar 104 having such a configuration facing the guided surface of the moving body 30. Then, an electrostatic attraction force is generated between the guide surface and the guided surface.

Next, another example of the hydrostatic gas bearing using the bipolar electrostatic attracting body according to the present embodiment will be described with reference to FIG.
In FIG. 4A, an X guide bar 104 serving as a guide is provided.
In the guide surface of, two electrodes 32a and 32b are formed by dividing the guide surface 104a into two over the entire moving direction (indicated by an arrow in the figure) of the moving body 30. The electrode 32a is connected to one polarity side of the power supply 40, and the electrode 32b is connected to the power supply 40.
Is connected to the other polarity side. On the other hand, in FIG. 4B, no electrode is formed on the gas ejection portion 102 of the moving body 30 which is a dielectric. When a predetermined voltage is applied between the electrode 32a and the electrode 32b from the power supply 40 with the guide surface of the X guide bar 104 having such a configuration facing the guided surface of the moving body 30, the guide surface and the guided surface are , An electrostatic attraction force is generated.

Also in the case of the static pressure gas bearing shown in FIGS. 3 and 4, the electrostatic attraction force is applied to the gas ejection portion 102 of the moving body 30.
And the guide surface of the X guide bar 104, on the same surface as the repulsive force due to the pressure of the static pressure gas by the gas ejection portion 102. Therefore, for example, even if a plurality of moving bodies 30 shown in FIG. 3B or FIG. 4B are mounted on the Y guide bar transport body 101 in FIG. No force is generated.

In the case of these bipolar electrostatic attraction members, since the electrostatic attraction force is greatly affected by the shape of the components, it is necessary to design a bipolar electrostatic attraction member in order to obtain a desired attraction force. Numerical analysis needs to be performed. Further, the electrostatic attraction force obtained by the bipolar electrostatic attraction member is relatively considerably smaller than that of the monopolar electrostatic attraction member.

However, as shown in FIG. 2, a static pressure gas bearing using a single-pole type electrostatic attraction member that forms electrodes on both the moving body 30 and the guide body 104 is provided by the power source 40 and the moving body 30. Wiring must be applied to both of the guides 104. In particular, since the moving body 30 must be moved while dragging the wiring, it is necessary to pay attention to the routing of the wiring. In the case of a static pressure gas bearing using a bipolar electrostatic suction body, the wiring from the power supply 40 can be integrated into either the guide body 104 or the moving body 30, so that there is an advantage that the handling is easy. doing. In particular, the bipolar hydrostatic gas bearing in which the plurality of electrodes 32a and 32b are formed on the guide body 30 shown in FIG.
Wiring connection is easier.

As shown in FIGS. 2 and 4, in the case of a hydrostatic gas bearing in which electrodes are formed on the guide surface 104a of the guide body 104 in the entire moving direction of the movable body 30, the movable body 30
Since the electrostatic attraction force is acting on other than the guiding surface 104a facing the above, it may be necessary to take measures such that the dust and the like in the atmosphere are sucked and the dust and the like do not adhere to the electrodes. In the case of a hydrostatic gas bearing in which electrodes are provided only on the moving body 30 side as shown in the drawing, it is advantageous in that it is not necessary to take such measures. In any case, any one of the hydrostatic gas bearings according to the present embodiment illustrated in FIGS. 2 to 4 based on the design specifications, the purpose of use, and the like of the stage device on which the hydrostatic gas bearing according to the present embodiment is mounted. You just have to select

In this embodiment, the X guide bar 104 and the moving body 30 are made of alumina ceramics. Further, an insulating film is formed on the surface of each electrode so that even if the supply of the static pressure gas is stopped, the two electrodes are not in direct contact with each other and short circuit occurs.

As described above, in the hydrostatic gas bearing according to the present embodiment, both the moving body and the guide are made of the dielectric material, and both the bearing surface of the hydrostatic gas bearing of the moving body and the guide surface of the guide are formed. Alternatively, it is characterized in that an electrode is formed on one of them by vapor deposition and a voltage is applied to generate an attraction force between the guide body and the moving body to balance the repulsion force of the static pressure gas.

According to the hydrostatic gas bearing of the present embodiment having the above-described configuration and operation, a dielectric can be used as the material of the guide and the moving body because the attractive force of static electricity is used. Therefore, stones or ceramics used for components of ordinary static pressure gas bearings can be used for the guide and the moving body.

In the conventional static pressure gas bearing, a region for providing a preload magnet and a vacuum pocket is required beside the gas ejection portion in order to generate a repulsive force. In such a case, these devices become unnecessary, so that the device can be downsized.

The hydrostatic gas bearing is used in a state where relatively large forces having different directions are balanced between the guide body and the moving body. According to the hydrostatic gas bearing according to the present embodiment, Since the generated electrostatic attraction force can be generated on the same surface as the repulsion force due to the pressure of the static pressure gas, it is necessary to prevent the components and the like supporting the moving body of the static pressure gas bearing from causing distortion or deformation. Can be

Therefore, in the stage device equipped with the static pressure gas bearing according to the present embodiment, the repulsive force due to the pressure of the static gas and the preload magnet, which are problems in the stage device equipped with the conventional static pressure gas bearing, Since the point of action differs from the suction force due to the vacuum pocket and the vacuum pocket, there is no problem that distortion or deformation occurs in the support member of the hydrostatic gas bearing.

[0049]

As described above, according to the present invention, it is possible to realize a small and inexpensive static pressure gas bearing which does not cause distortion in the moving body. Further, it is possible to realize a stage device in which the moving body is not deformed by the pressure of the static air or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a stage device using a hydrostatic gas bearing according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a hydrostatic gas bearing according to an embodiment of the present invention.

FIG. 3 is a diagram showing another configuration of the hydrostatic gas bearing according to the embodiment of the present invention.

FIG. 4 is a diagram showing still another configuration of the hydrostatic gas bearing according to one embodiment of the present invention.

FIG. 5 is a view showing a conventional hydrostatic gas bearing.

[Explanation of symbols]

 Reference Signs List 1 surface plate 5 sample table 16, 17 laser interferometer 16A, 17A laser beam 18, 19 moving mirror 20 wafer 30 moving body 32, 34 electrode 36 groove 38 gas ejection part 30, 50 moving body 40 power supply 52 static pressure gas bearing 54 Preload vacuum section 56 Preload magnet 101 Y guide bar carrier 102 Gas ejection section 104 X guide bar 104a Guide surface 106 Vertical support 111A, 111B X direction bearing 112 Y guide bar

Claims (5)

[Claims] 1. A gas ejecting section for producing a repulsive force between a guide body having a guide surface and formed of a dielectric, and ejecting a gas to the guide surface to generate a repulsive force between the guided surface facing the guide surface. And a moving body made of a dielectric material, and electrostatic attraction force generating means for generating an electrostatic attraction force between the guide surface and the guided surface. Gas bearing. 2. The static pressure gas bearing according to claim 1, wherein said electrostatic attraction force generating means applies a predetermined voltage between said electrodes formed on said guide surface and said guided surface and between said electrodes. And a voltage applying means. 3. The static pressure gas bearing according to claim 1, wherein said electrostatic attraction force generating means includes a plurality of electrodes formed on one of said guide surface and said guided surface, and said plurality of electrodes. A static pressure gas bearing having voltage applying means for applying a predetermined voltage therebetween. 4. The static pressure gas bearing according to claim 1, wherein the gas ejection portion is formed in the guided surface, and has a plurality of gas ejection holes for ejecting gas to the guide surface. A hydrostatic gas bearing characterized by having: 5. A stage device provided with a stage fixed to a movable body and movable in a guide direction of a guide body, comprising the hydrostatic gas bearing according to any one of claims 1 to 4. Stage equipment.