JPH03173784A - Vacuum vessel - Google Patents

Abstract

PURPOSE:To protect a vacuum sealing material from gas and plasma and to drastically inhibit deteriorating velocity by constituting a vacuum vessel so that a protective cap having a projecting part projected to the inside is gaplessly inserted into a window part provided to the outer wall of a vessel. CONSTITUTION:A vacuum sealing material 2 made of rigid rubber such as fluororesin or a metallic O-ring such as steel is arranged to a window part which is opened in one part of the outer wall 1 of a vacuum vessel made of material such as stainless steel. The projecting part 7 of a protective cap 4 is gaplessly inserted into a window part. The cap 4 is fixed to the outer wall 1 of the vessel by a cap presser 3. Further the projecting part 7 is formed integrally together therewith by the homogeneous material as the cap 4. The gap 6 of the window part is made extremely small by presence of the projecting part 7. As a result, it can be made little that corrosive gas and active gas, etc., infiltrate into the sealing material 2 through the gap 6. Therefore plasma is not caused in the vicinity of the sealing material 2 and deterioration of the sealing material 2 is reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cap structure for a vacuum container in which a workpiece is processed by introducing a gas into a vacuum or generating an electric field, and is mainly applied to semiconductor products. Targets manufacturing equipment for manufacturing.

[Conventional technology]

Dry etching equipment and CVD (chemical vapor deposition) equipment for semiconductor device manufacturing use corrosive gases (ammonia, chlorine, carbon tetrachloride, boron trichloride, silicon tetrachloride, etc.) and active gases (Oz or CF4), and has a structure that generates plasma discharge within it, and the protective camp in the viewing window, sensor port, or blind lid on the side of the container must be kept tightly sealed. .

The structure of a conventional cap is such that a plate-shaped cap member 4 is applied from the outside to the window 5 of the container, and a vacuum sealing material 2 is inserted between the outer wall of the container and the cap member, as shown in FIG. The cap was fixed to the outer wall l by means such as a cap holder 3.

[Problem to be solved by the invention]

In the conventional technology, no consideration is given to the shape or structure of the material of the vacuum sealing material in the protective cap. That is, as shown in FIG. 2, the surface of the cap member 4 in contact with the container is flat, and the distance from the opening (window) of the container to the sealing material 2 is extremely short. General vacuum sealing materials, such as O-rings made of hard rubber, allow corrosive gas or active gas introduced into the container to easily come into contact with the outer wall of the container through the gap 6, and when plasma is generated in the vacuum container, the The rate of deterioration of the sealing material becomes extremely high, and the generation of foreign matter and vacuum leaks from the vacuum sealing material itself, which impede processing in vacuum and result in defective processed products.

The present invention is intended to solve the above-mentioned problems,
The purpose of this is to protect the vacuum sealing material from gas and plasma in the vacuum container and to significantly reduce the rate of deterioration.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a vacuum container having a protective camp fixed from the outside of the container so as to seal a window provided on the outer wall of the container, wherein the protective cap has a protrusion that projects inward. It is characterized by being inserted into the window portion without any gaps.

[Effect]

By providing a protruding part on the protective cap and making it fit into the window without leaving any gaps, corrosive gases and active gases inside the container are difficult to enter into the area where the vacuum sealing material is located, and the effects of plasma discharge are also reduced. This greatly reduces the occurrence of accidents such as foreign matter and vacuum leaks due to deterioration of the vacuum sealing material itself.

【Example〕

Hereinafter, an embodiment in which the present invention is applied to a dry etching apparatus will be described with reference to the drawings.

FIG. 1 is a partial sectional view showing a protective cap structure in a vacuum container.

1 is an outer wall of a vacuum container made of a material such as stainless steel, and a part of the outer wall is open as a window 5.

Reference numeral 2 denotes a vacuum sealing material, which is made of hard rubber such as fluororesin or metal such as copper, and is called an O-ring.

Reference numeral 3 denotes a cap holder, which is adapted to fix the cap to the outer wall of the container using tightening tools such as bolts and nuts (not shown).

4 is a protective cap, and in the case of a viewing window, it is a transparent 5i
It can be made of a plate of oz or glass, or in the case of a blank lid it can be a plate of an opaque material, for example a metal plate.

Reference numeral 7 denotes a protrusion, which is made of the same material as the protective cap 4 and is integrally formed therewith, and is inserted into the window facing the inside of the container (low pressure side, vacuum side).

Due to the presence of this protruding portion 7, the gap 6 with the window portion is extremely small. As a result, the intrusion of corrosive gases, active gases, etc. into the vacuum sealing material through gaps is reduced.
There is no plasma generation near the vacuum sealing material, and deterioration of the sealing material can be reduced.

〔Effect of the invention〕

The present invention is configured as described above, and the influence on the sealing material due to discharge of gas or plasma in the container can be minimized, and troubles such as the generation of foreign matter and vacuum leaks can be greatly reduced, and the It has the effect of eliminating defects.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view of a vacuum container showing an embodiment of the present invention. Figure 2 is a partial sectional view of a conventional container.
Vacuum container outer wall, 2... Vacuum seal, 3... Camping holder, 4... Protective cap, 5... Window, 6...
...Gap, 7...Protrusion.

Claims (2)

[Claims] 1. A vacuum container having a protective cap fixed from the outside of the container so as to seal a window provided on the outer wall of the container, wherein the protective cap is fitted into the window without a gap by a protrusion projecting inward. A vacuum container characterized by: 2. In the vacuum container according to claim 1, a corrosive gas or an active gas is introduced into the container.