JP2002257138A - Static pressure fluid bearing device, stage device using the same, exposure device, and manufacturing method for device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively recover working fluid of a static fluid bearing device used in a vacuum chamber. SOLUTION: An exhaustgroove 13 surrounding a static pad 11 is provided in a static pad unit held by a movable body such as a wafer stage, etc., in a vacuum chamber to directly exhaust outside of a vacuum chamber by a vacuum pump through an exhaust hole 15 penetrating a support member 12 and a tube not shown in a drawing. Since the exhaust gas is effectively recovered every static pad unit, the bearing is not enlarged and it is preferably used for two-dimensional transfer stage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrostatic bearing device used for an exposure apparatus for manufacturing semiconductor devices, liquid crystal panels, etc., a positioning stage of various precision measuring devices, and a stage apparatus using the same. , An exposure apparatus, and a device manufacturing method.

[0002]

2. Description of the Related Art Various precision measuring apparatuses and exposure apparatuses for manufacturing semiconductors require a high-precision stage apparatus for positioning a workpiece or a substrate such as a wafer. In recent years, in particular, a configuration in which a portion between a movable stage for positioning and a guide is kept in non-contact by a hydrostatic bearing device has been widely used.

On the other hand, an X-ray electron beam exposure apparatus and an EUV exposure apparatus which have been developed for manufacturing a semiconductor device or the like which has been miniaturized are a vacuum chamber in which a high vacuum is maintained to prevent attenuation of an electron beam and EUV. When a hydrostatic bearing device is used for a wafer stage or the like that performs positioning for exposing a substrate such as a wafer inside the chamber, the working fluid in the bearing gap is discharged into the vacuum chamber, and the vacuum state of the vacuum chamber is maintained. It becomes difficult.

Therefore, in the stage device provided in the vacuum chamber, a bellows is provided between the movable portion of the hydrostatic bearing and the guide surface, a tube is connected to the bellows, and the working fluid in the bearing gap is passed through the tube. (U.S. Patent Publication No. 578).
No. 4925).

Further, in the case of a radial type linear motion bearing, a configuration is known in which a fluid in a bearing gap is exhausted by a vacuum pump through an exhaust groove provided on a housing side forming a guide (US Pat. No. 4,726,689). No.).

[0006]

However, according to the above prior art, there are the following unsolved problems.

When a bellows is used between the movable portion and the guide surface of the hydrostatic bearing device, an external force due to expansion and contraction of the bellows is applied when the movable portion moves, which is a characteristic of the hydrostatic bearing. Eliminates low friction effects. Further, in a 24-hour production environment such as a semiconductor factory, an accident or the like in which a large amount of fluid flows into the vacuum chamber due to cracking due to fatigue of the bellows is expected.

In addition, the method of evacuating the housing of the radial bearing using the exhaust groove requires a large number of vacuum pumps, has the problem that the overall size of the bearing is large and heavy, and has a problem in that the XY stage is difficult. It is not suitable for stages that perform dimensional motion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned unsolved problems of the prior art, and is a lightweight hydrostatic bearing device suitable for a high-precision positioning stage used in a high vacuum state. It is another object of the present invention to provide a stage apparatus, an exposure apparatus, and a device manufacturing method using the same.

[0010]

In order to achieve the above object, a hydrostatic bearing device of the present invention comprises at least one hydrostatic pad unit for supplying a working fluid between a guide and a moving body facing each other. Wherein the static pressure pad unit has a static pressure pad facing the guide or the moving body, a support member for supporting the static pressure pad, and an opening around the static pressure pad through the support member. And a vacuum exhaust means connected to the exhaust hole.

It is preferable that an exhaust groove surrounding the outer periphery of the static pressure pad is provided at the opening of the exhaust hole of the support member of the static pressure pad unit.

A labyrinth seal forming portion for forming a labyrinth seal for preventing the working fluid from flowing out of the outer peripheral edge of the hydrostatic pad unit may be provided outside the exhaust groove of the support member.

The gap size of the labyrinth seal forming portion of the support member is preferably equal to or larger than the gap size of the hydrostatic pad.

It is preferable that at least two exhaust grooves surrounding the outer periphery of the static pressure pad are provided, each of which is connected to an individual vacuum exhaust means.

In a configuration in which at least two exhaust grooves surrounding the outer circumference of the static pressure pad are provided, one of the exhaust grooves closest to the static pressure pad may be open to the atmosphere.

A stage device according to the present invention includes a linear moving stage provided with the above-described hydrostatic bearing device.

[0017] In addition, the above-described hydrostatic bearing device having the hydrostatic bearing device 2
A stage device having a dimensional movement stage may be used.

[0018]

An exhaust groove is provided around the static pressure pad of each static pressure pad unit, and the working fluid ejected from the static pressure pad is immediately collected by the vacuum exhaust means, so that the working fluid is discharged from the outside of the static pressure pad unit. To prevent spillage.

If the labyrinth seal forming portion is provided outside the exhaust groove, the leakage of the working fluid of the hydrostatic pad unit can be almost completely prevented. An extremely suitable hydrostatic bearing device can be realized as the guide portion.

In addition, since the working fluid is recovered by the vacuum exhaust means for each static pressure pad unit, 2
It can be used for a dimensional moving stage device.

By mounting such a hydrostatic bearing device, it is possible to greatly reduce the weight of a stage device such as a wafer stage for performing high-precision positioning in a vacuum chamber.

[0022]

Embodiments of the present invention will be described with reference to the drawings.

FIGS. 1 and 2 are schematic sectional views showing a main part of the hydrostatic bearing device according to the first embodiment. This is for keeping a linear moving stage such as a wafer stage or a two-dimensional moving stage, which is a moving body, disposed in a vacuum chamber (not shown) in non-contact with a guide surface 10 such as a surface plate as a guide. It has at least one static pressure pad unit, and the atmosphere in the vacuum chamber is maintained at a high vacuum.

Each of the static pressure pad units is composed of a static pressure pad 11 such as a porous pad disposed opposite the guide surface 10.
And a support member 12 having a pad support portion 12a which is a static pressure pad support portion for supporting the static pressure pad 11 and a labyrinth seal forming portion 12b surrounding the pad support portion 12a. On the side,
Generally, a plurality of static pressure pad units are held.

On the lower surface of the support member 12, a static pressure pad 11
The exhaust groove 13 is formed so as to surround the outer periphery of.

The compressed gas as the working fluid is supplied to the support member 12.
Is supplied to the static pressure pad 11 from an air supply hole 14 penetrating through the pad support portion 12a of the pad, and is ejected toward the guide surface 10. The exhaust groove 13 is directly connected to a vacuum pump, which is a vacuum exhaust unit provided outside the vacuum chamber, via an exhaust hole 15 and a tube (not shown).

The labyrinth seal forming portion 12b forms a labyrinth seal 16 facing the guide surface 10 to prevent the working fluid from leaking out of the hydrostatic pad unit.

In order to reduce the weight of the hydrostatic pad unit, the thickness of the collar forming the labyrinth seal forming portion 12b of the support member 12 is made as small as possible, and the labyrinth seal forming portion 12b and the pad supporting portion are formed. The space between the support member 12a and the support member 12a is reduced in a stepwise manner so that an unnecessary material is omitted.

A compressed gas is supplied from a compressed gas source provided outside the vacuum chamber to the air supply hole 14 through a tube, and the gas ejected from the static pressure pad 11 is supplied to the guide surface 1.
To form a high pressure gaseous film that can support the weight of the stage in the bearing gap of the gap size D ₁ of the between 0. Most of the gas discharged from the bearing gap is sucked by the vacuum pump from the exhaust groove 13 through the exhaust hole 15, and the remaining gas flows out to the atmosphere in the vacuum chamber through the gap of the labyrinth seal 16. The gas flowing into the vacuum chamber is forcibly exhausted by a chamber vacuum pump (not shown), and the inside of the vacuum chamber is maintained at a desired degree of vacuum.

Here, the clearance dimension D ₂ of the labyrinth seal 16 is the clearance dimension D ₁ of the bearing clearance by the hydrostatic pad 11.
Or as wide as a few microns.

According to the present embodiment, an exhaust groove surrounding the outer edge of the static pressure pad for ejecting gas is provided, and a collar-shaped labyrinth seal is provided at the outermost edge of the support member for supporting the static pressure pad. A labyrinth seal is formed by the part to prevent the gas in the bearing gap from flowing out to the atmosphere in the vacuum chamber, and the majority of the gas in the bearing gap is directly discharged to the support member exhaust groove for each hydrostatic pad unit. Therefore, the gas, which is the working fluid of the hydrostatic bearing device, can be collected very efficiently out of the vacuum chamber. Therefore, it is easy to maintain a desired high vacuum state even when used for a stage device in a vacuum chamber.

Further, by forming the labyrinth seal forming portion of the support member into a thin brim shape as compared with the pad support portion at the central portion, the entire hydrostatic pad unit is reduced in size, and the hydrostatic bearing device is reduced in weight. Can be greatly promoted.

FIG. 3 shows a first modification. This is because the outer peripheral portion of the support member 22 is pyramid-shaped including the labyrinth seal forming portion 22b to reduce the weight.

FIG. 4 shows a second modification, in which the labyrinth seal forming portion 32b of the support member 32 is made thinner in a wide area, and the exhaust hole 15 directly communicating with the exhaust groove 13 from the back thereof.
By forming, it is possible to contribute to further weight reduction.

The overall shape of the static pressure pad unit is as follows:
The shape is not limited to the rectangular shape shown in FIG. 2 and may be a disk shape or the like, or a radial bearing used for a rotary stage or the like in addition to a two-dimensionally or linearly moving XY stage or the like such as a wafer stage. May be.

FIGS. 5 and 6 show a main part of a hydrostatic bearing device according to a second embodiment. The static pressure pad unit includes a static pressure pad 11 such as a porous pad for ejecting a fluid to the guide surface 10, a pad support 52 a serving as a static pressure pad support for supporting the static pressure pad 11, and its surroundings. The support member 52 has a surrounding labyrinth seal forming portion 52b, and the lower surface of the support member 52 has exhaust grooves 53a, 53 that double surround the outer periphery of the hydrostatic pad 11.
b is formed. Since the guide surface 10 and the static pressure pad 11 are the same as those in the first embodiment, they are denoted by the same reference numerals and description thereof is omitted.

The compressed gas as the working fluid is supplied to the support member 52.
Is supplied to the static pressure pad 11 from an air supply hole 54 penetrating through the pad support portion 52a of the pad, and is ejected toward the guide surface 10. The exhaust grooves 53a, 53b are respectively provided with exhaust holes 55a,
It is individually and directly connected to two vacuum pumps 1 and 2 installed outside the vacuum chamber via a tube 55b and a tube (not shown). The inner exhaust groove 55a closer to the static pressure pad 11 may be open to the atmosphere.

The labyrinth seal forming portion 52b is provided with a double labyrinth seal 56a, 56b facing the guide surface 10.
To prevent fluid leakage out of the hydrostatic pad unit.

In order to reduce the weight of the static pressure pad unit, the thickness of the collar forming the labyrinth seal forming portion 52b of the support member 52 is made as small as possible, and the labyrinth seal forming portion 52b and the pad supporting portion 52a are formed. The step between them is stepped, so that unnecessary material is omitted, and the weight of the entire support member 52 is reduced.

Compressed gas is supplied from a compressed gas source provided outside the vacuum chamber to the air supply hole 54 through a tube, and gas ejected from the static pressure pad 11 is applied to the guide surface 1.
To form a high pressure gaseous film that can support the weight of the stage in the bearing gap of the gap size D ₁ of the between 0. Most of the gas flowing out of the bearing gap is exhausted from the exhaust grooves 53a and 53b through the exhaust holes 55a and 55b, and the remaining gas is exhausted to the atmosphere in the vacuum chamber through the labyrinth seals 56a and 56b. The gas discharged into the vacuum chamber is forcibly exhausted by a vacuum pump for a vacuum chamber (not shown), and a desired degree of vacuum is maintained in the vacuum chamber.

Here, the labyrinth seals 56a, 56b
The gap dimension D ₂ is equal to or gap dimension D ₁ of the bearing gap,
Or it may be several microns wider.

According to the present embodiment, a plurality of exhaust grooves surrounding the outer edge of the static pressure pad for ejecting gas are provided, and the collar-shaped labyrinth seal forming portion provided on the outermost edge of the support member is also provided with double exhaust grooves. The labyrinth seal is formed to more reliably prevent the gas in the bearing gap from flowing out to the atmosphere in the vacuum chamber, and most of the gas in the bearing gap is removed through the exhaust groove and the exhaust hole of the support member. It is forcibly discharged out of the vacuum chamber by a direct vacuum pump or the like, and the gas ejected from the static pressure pad of each static pressure pad unit is collected very efficiently outside the vacuum chamber, and the vacuum state in the vacuum chamber is reduced. Can be maintained.

Further, by forming the labyrinth seal forming portion of the support member into a thin brim shape as compared with the central pad support portion, the hydrostatic bearing device can be significantly reduced in weight.

FIG. 7 shows a first modification of the second embodiment. This is because the outer peripheral portion of the support member 62 has a pyramid shape including the labyrinth seal forming portion 62b,
It is lighter.

FIG. 8 shows a second modification of the second embodiment, in which a labyrinth seal forming portion 7 of a support member 72 is formed.
2b is thinned over a wide area, and the exhaust groove 53
By forming the exhaust holes 55a and 55b communicating with the a and 53b, it is possible to further reduce the weight.

The overall shape of the hydrostatic bearing device is not limited to the rectangular shape shown in FIG. 5, but may be a disk shape or the like, other than an XY stage or the like that moves two-dimensionally. Alternatively, a radial bearing used for a rotary stage may be used.

FIG. 9 shows an exposure apparatus for manufacturing a semiconductor device using a stage device using a hydrostatic bearing device similar to the above as a guide portion as a wafer stage. Surface plate 101
Has fixed the linear motor stators F ₁ of the guide 102 and the linear motor M ₁ above, the linear motor stators F ₁ is a multi-phase electromagnetic coil, the linear motor movable element L ₁ is a group of permanent magnets I have. The movable portion of the linear motor movable element L ₁ 10
3, connected to the movable guide 104 is a linear drive stage, the movable guide 104 by the driving of the linear motor M ₁
Is moved in the direction normal to the paper surface. The movable part 103 is a surface plate 1
01 is supported by a static pressure pad unit 105 based on the upper surface, and is supported by a static pressure pad unit 106 based on the side surface of the guide 102.

A moving stage 107, which is a two-dimensional moving stage arranged so as to straddle the movable guide 104, is supported on the surface plate 101 by a static pressure pad unit 108. The movable stage 107, by a linear motor M ₂ similar to the above, the movable stage 107 is moved in the left-right direction relative to the movable guide 104. The movement of the moving stage 107 is measured using a mirror 109 and an interferometer 110 fixed to the moving stage 107.

A wafer W as a substrate is held on a chuck mounted on a moving stage 107, and a light source 111 and a projection optical system 1 are used to print a circuit pattern on the wafer W.
12, the circuit pattern on the reticle R as the original is reduced and transferred onto the wafer W.

Next, an embodiment of a device manufacturing method using the above exposure apparatus will be described. FIG. 10 shows a semiconductor device (IC
Chips such as LSIs and LSIs, or liquid crystal panels and CCs
D) etc. are shown. In step 1 (circuit design), the circuit of the semiconductor device is designed. Step 2 is a process for making a mask on the basis of the circuit pattern design. In step 3 (wafer manufacture), a wafer is manufactured using a material such as silicon. Step 4 (wafer process) is referred to as a pre-process in which an actual circuit is formed on the wafer by the lithography technique using the exposure apparatus, using the prepared mask and wafer.
Step 5 (assembly) is called a post-process, and is a process of forming a semiconductor chip using the wafer produced in step 4, and includes processes such as an assembly process (dicing and bonding) and a packaging process (chip encapsulation). . In step 6 (inspection), inspections such as an operation confirmation test and a durability test of the semiconductor device manufactured in step 5 are performed. Through these steps, a semiconductor device is completed and shipped (step 7).

FIG. 11 shows a detailed flow of the wafer process. Step 11 (oxidation) oxidizes the wafer's surface. Step 12 (CVD) forms an insulating film on the wafer surface. Step 13 (electrode formation) forms electrodes on the wafer by vapor deposition. In step 14 (ion implantation), ions are implanted into the wafer. Step 1
In 5 (resist processing), a photosensitive agent is applied to the wafer. Step 16 (exposure) uses the above-described exposure apparatus to print and expose the circuit pattern of the mask onto the wafer. Step 17 (development) develops the exposed wafer. In step 18 (etching), portions other than the developed resist image are removed. In step 19 (resist stripping), unnecessary resist after etching is removed. By repeating these steps, multiple circuit patterns are formed on the wafer. By using the manufacturing method of this embodiment, it is possible to manufacture a highly integrated semiconductor device which has conventionally been difficult to manufacture.

[0052]

Since the present invention is configured as described above, the following effects can be obtained.

The gas, which is the working fluid of the hydrostatic bearing device used in the vacuum chamber, can be efficiently recovered, and the weight of the stage device, which performs high-precision positioning by two-dimensional movement, can be greatly reduced. . By using such a stage device equipped with a hydrostatic bearing for a wafer stage or the like of an exposure apparatus, it is possible to contribute to miniaturization and cost reduction of semiconductor devices and the like.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a main part of a hydrostatic bearing device according to a first embodiment.

FIG. 2 is a plan view showing the apparatus of FIG.

FIG. 3 is a schematic cross-sectional view showing a first modification of the first embodiment.

FIG. 4 is a schematic cross-sectional view showing a second modification of the first embodiment.

FIG. 5 is a plan view showing a second embodiment.

FIG. 6 is a schematic cross-sectional view taken along line AA of FIG.

FIG. 7 is a schematic cross-sectional view showing a first modification of the second embodiment.

FIG. 8 is a schematic cross-sectional view showing a second modification of the second embodiment.

FIG. 9 is a diagram illustrating an exposure apparatus.

FIG. 10 is a flowchart showing a semiconductor device manufacturing process.

FIG. 11 is a flowchart showing a wafer process.

[Explanation of symbols]

Reference Signs List 10 Guide surface 11 Static pressure pad 12, 22, 32, 52, 62, 72 Support member 12a, 52a Pad support portion 12b, 22b, 32b, 52b, 62b, 72b
Labyrinth seal forming part 13, 53a, 53b Exhaust groove 14 Air supply hole 15, 55a, 55b Exhaust hole 16, 56a, 56b Labyrinth seal

Claims (11)

[Claims] 1. A static pressure pad unit for supplying a working fluid between a guide and a moving body opposed to each other, wherein the static pressure pad unit is a static pressure pad unit opposed to the guide or the moving body. A hydrostatic bearing having a pad, a support member for supporting the hydrostatic pad, and vacuum exhaust means connected to an exhaust hole passing through the support member and opening around the hydrostatic pad. apparatus. 2. The hydrostatic bearing device according to claim 1, wherein an exhaust groove surrounding the outer periphery of the static pressure pad is provided at an opening of the exhaust hole of the support member of the static pressure pad unit. 3. A labyrinth seal forming portion for forming a labyrinth seal for preventing a working fluid from flowing out of an outer peripheral edge of the hydrostatic pad unit is provided outside the exhaust groove of the support member. The hydrostatic bearing device according to claim 2, wherein 4. The hydrostatic bearing device according to claim 3, wherein the clearance dimension of the labyrinth seal forming portion of the support member is equal to or larger than the clearance dimension of the hydrostatic pad. 5. The vacuum pump according to claim 2, wherein at least two exhaust grooves surrounding the outer periphery of the static pressure pad are provided, and each of the exhaust grooves is connected to a separate vacuum exhaust means. Hydrostatic bearing device. 6. A structure in which at least two or more exhaust grooves surrounding the outer periphery of a static pressure pad are provided, one of which is closest to the static pressure pad is open to the atmosphere. The hydrostatic bearing device according to any one of claims 2 to 5. 7. The weight of the supporting member is reduced by omitting an unnecessary portion between the static pressure pad supporting portion for supporting the static pressure pad and the labyrinth seal forming portion. The hydrostatic bearing device according to claim 1. 8. A stage device having a linear moving stage provided with the hydrostatic bearing device according to claim 1. Description: 9. A stage device having a two-dimensional moving stage equipped with the hydrostatic bearing device according to claim 1. Description: 10. An exposure apparatus, wherein at least one of a substrate and an original is positioned by the stage device according to claim 8. 11. A device manufacturing method comprising a step of exposing a substrate by the exposure apparatus according to claim 10.