JPH11241155A - Sealing member and vacuum device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air tight seal suitable for forming a high vacuum envi ronment and durable against the use at high temp. SOLUTION: The surface of an O-ring like sealant 401 is covered with a coating film of a heat resistant polymer. As the O-ring like sealant, a silicone rubber is used and as the heat resistant polymer, a polyimide is used. Vacuum seal free from the permeation of a light element such as hydrogen, helium and capable of being used at high temp. is obtained by using a sealing member composed of the O-ring like sealant and a covering member 402 of a heat resistant polymer, which has a center part and two legs extending from both end of the center part and receiving the sealant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing member for hermetically sealing a vacuum device for processing an object to be processed under reduced pressure, and a vacuum device hermetically sealed using the sealing member.

[0002]

2. Description of the Related Art Manufacturing processes of semiconductor devices, liquid crystal display devices and the like include a number of film forming processes and etching processes for forming patterns. These film forming processes and etching processes are performed in a reduced-pressure chamber. For example, plasma excitation CVD, sputtering, ion plating, and vacuum deposition, which are typical examples of the film forming process, are all performed in a reduced-pressure chamber.

[0003] These vacuum devices include a single type and a multi-chamber type in which a plurality of chambers are connected.
Each of the apparatuses generally has a load lock chamber for taking in and taking out the object to be processed into the apparatus, and one or a set of the objects to be processed are discharged through the opening of the load lock chamber. It can be put into the road lock room from the atmosphere. After closing the opening, the load lock chamber is depressurized and the object to be processed is shielded from the atmosphere. Thereafter, the transfer robot takes out the objects to be processed one by one from the openable gate on the apparatus side of the load lock chamber and transports them to a chamber evacuated to a high vacuum in advance, such as a film formation chamber or an etching chamber.

[0004] Regardless of whether the chamber is a single chamber or a multi-chamber system, many process chambers are kept at a high vacuum and must be free from contaminants. (Including the transfer chamber of the workpiece) must be hermetically sealed. On the other hand, a substance to be deposited, a substance to be etched, a substance to be processed, or a substance scattered from a target adheres to inner walls and internal parts of the film formation chamber, the etching chamber, and the like, and these adhered substances hinder the process. Therefore, it is necessary to clean the room quite frequently. For this reason, as disclosed in Japanese Patent Application Laid-Open No. 6-151365, the housing of the chamber is structured to be separable into an upper portion and a lower portion, and at the time of cleaning, the upper portion is separated to clean the inside. In addition, Japanese Unexamined Patent Publication No.
As disclosed in Japanese Patent Application Laid-Open No. 60997 and Japanese Patent Application Laid-Open No. 9-263944, the upper portion of the chamber is fixed to the side wall of the chamber as a top plate structure so that the top plate is removed and the inside is cleaned at the time of cleaning. Have been done. When such a separable housing structure is adopted, an O-ring is interposed in a gap between an upper portion and a lower portion or a joint portion between a top plate and a side wall to press and seal air-tightly.

In Japanese Patent Application Laid-Open No. 6-60997, in a plasma etching apparatus, a gap between an electrostatic chuck supporting a semiconductor wafer and a base is hermetically sealed with an O-ring.

As a sealing material for a vacuum seal, a fluorine-based rubber (product name, Viton) is widely used as disclosed in Japanese Patent Application Laid-Open No. Hei 9-263944. Viton seal has a temperature suitable for use. Range from -20 degrees C to 12
It is as narrow as 0 ° C. and is not suitable for use at high temperatures such as 300 ° C. Further, a sealing material obtained by coating Viton with Teflon having excellent chemical resistance is also used. In this case, Teflon itself can withstand a high temperature of 200 ° C., but since Viton is inferior in heat resistance, 10% as a whole.
It can only withstand temperatures of a few tens of degrees. As a sealing material that can withstand use at a high temperature of 200 ° C. to 250 ° C., there is a sealing material made of silicone rubber. The inventor of the present invention has recognized that this silicone sealing material has many pores and has a property of transmitting light elements such as hydrogen and helium, which is a problem in creating a high vacuum environment. .

Japanese Unexamined Patent Publication No. Hei 8-325734 discloses that in order to prevent degassing of rubber from a rubber sealing member in a thin film forming apparatus from entering a chamber, a rubber O member is used.
Cover the ring with a metal metal ring like a spring,
It is described that the inside of the chamber and the rubber O-ring are separated by a metal ring. In the seal part, a metal ring is sandwiched between the chamber wall and the lid to seal.However, since the metal is rigid in material, the contact area at the joint is small and it is necessary to establish sufficient confidentiality. There are difficulties. Further, since the material of the joint portion of the chamber must be harder than the metal of the sealing material, the design of the housing is restricted.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a hermetic seal suitable for creating a high vacuum environment and enduring use at high temperatures.

[0009]

Means for Solving the Problems The object of the present invention is to provide:
It is solved by the following means. That is, a seal member for hermetically sealing a vacuum device, the seal member comprising an O-ring-shaped seal material and a heat-resistant polymer film covering the surface of the seal material.

Further, the present invention has the following configuration in one aspect. That is, a vacuum device for processing an object to be processed under reduced pressure, wherein at least one of the gaps of the vacuum device is hermetically sealed by a sealing member obtained by coating an O-ring-shaped sealing material with a heat-resistant polymer film. Sealed vacuum equipment.

Further, the present invention has the following configuration in one aspect. That is, a sealing member for hermetically sealing a vacuum device, comprising an O-ring-shaped sealing member, and a heat-resistant polymer cover member having a central portion and two legs extending from both ends of the central portion and receiving the sealing member. ,
A sealing member in which the above-mentioned sealing material is fitted in a cover member.

The vacuum apparatus according to the present invention can have the following configuration. That is, a vacuum apparatus for processing an object to be processed under reduced pressure, wherein at least one of the gaps of the vacuum apparatus is hermetically sealed with the sealing member.

The above-mentioned O-ring-shaped sealing material is preferably made of silicone rubber having excellent heat resistance. The heat-resistant polymer is also called engineering plastic, and typical examples include polyimide, polyetheretherketone, and polyetherimide, and polyimide is the most common. The heat-resistant polymer can withstand a high temperature of 300 ° C. or more, but becomes hard when molded, and is not suitable for use as a single body as a sealing material. When this heat-resistant polymer is coated on the surface of silicone rubber sealing material with a thickness of several microns to several tens of microns, the elasticity of silicone rubber and the heat resistance of heat-resistant polymer combine to create a sealing member suitable for use at high temperatures. can get.

According to one aspect of the present invention, instead of coating with a heat-resistant polymer, a seal member made of a silicone rubber is inserted into a cover member made of a heat-resistant polymer to form a seal member. The seal member having this structure is installed in a vacuum device such that the side of the heat-resistant polymer cover member is on the vacuum side of the vacuum device.

The sealing member of the present invention can withstand use at a high temperature, can maintain sufficient contact in the gap of the vacuum device, and can be hermetically sealed. Light elements such as hydrogen and helium that have passed through the silicone rubber are prevented from entering the vacuum device by the heat-resistant polymer film or cover member, so that a high vacuum environment can be created.

[0016]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a schematic plan view of a multi-chamber apparatus for executing a film forming process or an etching process on a semiconductor wafer or a liquid crystal panel substrate as an object to be processed. The apparatus comprises a cassette station 5 for supplying a plurality of substrates to the apparatus, a plurality of process chambers 1, 2, 3, 4, and a transfer chamber 6 provided with a robot for transferring the substrates from the cassette station to the process chamber. .

FIG. 2 is a sectional view showing the relationship between the cassette station 5, the transfer chamber 6, and the process chamber 3 in FIG. The cassette station 5 is a chamber for receiving a cassette 22 containing a plurality of substrates 21 into the apparatus. The cassette station 5 is evacuated and depressurized by the exhaust system 57 after the cassette is inserted. When the pressure is reduced to a predetermined pressure, the gate 51 is opened and the exhaust system 6 is opened.
9, the robot 65 in the transfer chamber 6 maintained in a high vacuum in advance takes out the substrates 21 one by one from the cassette station 5 and transfers them to the process chambers 1, 2, 3 and 4 maintained in a high vacuum in advance. .

The transfer chamber 6 has a structure in which a top plate 61 is detachably attached to a housing body 62 of the transfer chamber 6. The top plate 61 is attached to the housing main body 62 by a plurality of fixing bolts, for example. Top plate 6
A seal member 63 according to the present invention is provided in a gap between the housing 1 and the housing body. When inspecting and repairing the robot 65 and cleaning the transfer chamber, the top plate 61 is removed.

The process chamber 3 is a sputter film formation chamber connected to an exhaust system 38 and maintained at a high vacuum, and the substrate 2 loaded through a gate 66 opened and closed from the transfer chamber 6.
1 is placed on the support base 36. For example, aluminum blown out of the aluminum target 37 is deposited on the substrate to form an aluminum thin film. The process chamber 3 is not limited to a sputter deposition chamber, but may be any chamber that accommodates a substrate under reduced pressure or vacuum, such as a vacuum deposition chamber, a plasma deposition chamber, a CVD chamber, a dry etching chamber, and a heating chamber. Good.

The process chamber 3 also has a structure in which a top plate 31 is detachably attached to a housing body via a seal member 32 by, for example, a plurality of fixing bolts, similarly to the transfer chamber. With such a configuration, the inside of the process chamber 3 can be cleaned or repaired by removing the top plate 31.

The substrate that has been processed in the process chamber 3 is sent to the next process chamber or cassette station 5 by the robot 65 in the transfer chamber 6. In this embodiment, the cassette station 5 is used for both loading and unloading substrates, but a cassette station for loading and a cassette station for unloading may be provided separately. When the processed substrate is stocked in the cassette station, the cassette station is returned to the atmospheric pressure and the substrate is taken out from the opening.

FIG. 3 is a cross-sectional view of a seal member according to the present invention. A polyimide film 302 having a thickness of several microns is formed on the surface of an O-ring seal material 301 made of silicone rubber. This sealing member is made of silicone rubber O.
It is formed by applying liquid polyimide (polyimide paste) to the ring, or by putting silicone rubber into a mold and injecting the polyimide paste, and drying at a temperature of 200 ° C. to 300 ° C. and several tens of degrees C.

FIG. 4 is a cross-sectional view showing another embodiment of the seal member according to the present invention, in which an O-ring seal member made of silicone rubber is provided on a generally ring-shaped cover member 402 having a substantially U-shaped cross section. 401 is fitted. The cover member 402 is formed by molding polyimide using a mold. The cover member 402 includes two legs 404 and 405 extending from both ends of a base portion 403 serving as the center of the cover member. At the tips of the two legs, slightly thicker tips 406 and 407 are provided. The outer surfaces of the tips 406 and 407 serve as sealing surfaces that come into contact with the housing, top plate, and the like of the vacuum device.

FIG. 5 shows another embodiment of the cover member of the present invention. The cover member 502 is formed by molding polyimide. Extending from the central base 503 are two legs 504 and 505 with their tips 506 and 507 thicker than the rest of the legs. An O-ring 501 of silicone rubber is fitted between the two legs. Tips 506 and 507
As shown in FIG. 6, the cross-sectional shape of the outer ring of the O-ring and the distal end portion 50 of the O-ring deformed into an elliptical shape by the pressing in a use state in which the sealing material is pressed in the gap of the vacuum device.
6 and 507 are joined together to form a wide flat sealing surface on the outer surfaces of the two legs.

The cover member of the present invention is intended to enhance the heat resistance of the seal member and to provide a seal member that does not allow the passage of light elements such as hydrogen and helium.
Various modifications are possible from the embodiment of FIGS. 4 and 5 as long as this purpose is met. For example, the base may be generally rounded in shape and have no boundary between the two legs. The base may be formed simply as a connection of the two legs. In addition, when giving a sufficient thickness to the leg itself, the tip of the leg does not need to be thicker than other portions, and may have a uniform thickness over the entire leg. Further, the leg portion may be gradually thickened from the base portion toward the tip.

The seal member in which the O-ring is fitted to the cover member shown in FIGS. 4, 5 and 6 is installed so that the base side of the cover member faces the vacuum side of the vacuum device, that is, the inside. Since the polyimide material is softer and easier to deform than metal, the pressure at the time of mounting the top plate causes the sealing surfaces of the tip portions 406 and 407 to be crushed and the cover member to be in contact with the joint of the vacuum device over a wide area. A tip can be formed. In addition, as described above with reference to FIG. 6, the O-ring that is deformed by pressing may be integrated with the leg of the cover member to form a large sealing area. These sealing members are
Since the elasticity of the silicone seal material and the elasticity of the base and legs of the cover member combine to provide strong elasticity, frequent cleaning and maintenance operations are performed, and the top plate is frequently disassembled and tightened. It provides sufficient elasticity over a long period of time without sagging. This seal member can withstand a high temperature of 300 ° C.

Although the embodiment of the present invention has been described above with reference to a multi-chamber apparatus, the present invention is not limited to such a multi-chamber apparatus, but can be applied to various single processing apparatuses. Further, the present invention is not limited to the hermetic seal of the gap between the top plate and the housing of the vacuum device, but can be applied to the hermetic seal of any gap of the vacuum device.

[0028]

According to the present invention, it is possible to obtain a hermetic seal that provides sufficient confidentiality to a vacuum device and withstands use at a high temperature, and also obtains a hermetic seal that prevents light elements such as hydrogen and helium from permeating. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a multi-chamber apparatus.

FIG. 2 is a diagram showing an AA ′ section of the device of FIG. 1;

FIG. 3 is a sectional view of the seal member according to the embodiment of the present invention.

FIG. 4 is a sectional view of a seal member according to another embodiment of the present invention.

FIG. 5 is a sectional view of a seal member according to another embodiment of the present invention.

FIG. 6 is a diagram showing a cross-sectional shape of the seal member of FIG. 6 in a used state.

[Explanation of symbols]

 1, 2, 3, 4 Process chamber (vacuum device) 5 Cassette station 6 Transfer chamber 21 Substrate 31, 61 Top plate 63, 32 Hermetic seal member 301, 401 O-ring seal material 302 Polyimide film 402 Polyimide cover member

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/3065 H01L 21/302 B

Claims (9)

[Claims] 1. A sealing member for hermetically sealing a vacuum device, comprising: an O-ring-shaped sealing member; and a heat-resistant polymer film covering a surface of the sealing member. 2. A vacuum apparatus for processing an object to be processed under reduced pressure, wherein at least one of the gaps of the vacuum apparatus is formed by covering an O-ring sealing material with a heat-resistant polymer film. A vacuum device characterized by being hermetically sealed with members. 3. A sealing member for hermetically sealing a vacuum device, comprising: an O-ring-shaped sealing member; a central base portion; and two legs extending from both ends of the base portion and receiving the sealing member. A seal member comprising a heat-resistant polymer cover member, wherein the seal member is fitted into the cover member. 4. A vacuum apparatus for processing an object to be processed,
At least one of the gaps of the vacuum device is provided with an O-ring-shaped sealing material; a heat-resistant polymer cover member having a central base portion and two legs extending from both ends of the base portion and receiving the sealing material; A vacuum device, which is hermetically sealed with a sealing member made of: 5. The cover member is characterized in that the distal ends of the two legs are slightly thick, and when pressed, the outer surfaces of the distal ends are crushed to form a sealing surface. The vacuum device according to claim 4. 6. The seal member according to claim 3, wherein the two leg portions of the cover member are shaped so as to be fitted with an outer wall of the seal material that is deformed when the seal member is used. 7. The vacuum apparatus according to claim 4, wherein the two legs of the cover member are formed so as to be fitted with an outer wall of the sealing material that is deformed when the sealing member is used. 8. The sealing member according to claim 1, wherein the sealing material is made of silicone rubber, and the heat-resistant polymer is polyimide. 9. The vacuum apparatus according to claim 2, wherein the sealing material is made of silicone rubber, and the heat-resistant polymer is polyimide.