JP2023010480A - Groove-matched ultra-low gas permeability composite seal with rubber o-ring seal and backup ring seal integrated - Google Patents

Abstract

To provide a groove-matched ultra-low gas permeability composite seal with a backup ring seal and a rubber O-ring seal integrated, which improves sealing performance without impairing handleability of the rubber O-ring seal.SOLUTION: A groove-matched ultra-low gas permeability composite seal is configured such that like a rubber O-ring seal 203 and a backup ring seal 103, a concave part of the backup ring seal 103 is formed into a dovetail groove shape, and the backup ring seal 103 and the rubber O-ring seal 203 are structurally integrated.SELECTED DRAWING: Figure 8

Description

The present invention relates to a dovetail groove compatible ultra-low gas permeability composite seal that integrates a backup ring seal and a rubber O-ring seal to improve the sealing performance without impairing the handling properties of the rubber O-ring seal. .

Compared to metal seals, it is easier to handle, less expensive, more compatible with the mating sealing surface, and is compatible with the mating sealing surface in equipment that uses vacuum such as semiconductor manufacturing equipment or analytical equipment. Rubber 0-ring seals are often used because they are resistant to displacement of the seal surface due to differences in thermal expansion coefficients, etc. However, in recent years, further miniaturization in the semiconductor manufacturing process, or measurement and analysis In order to further improve the accuracy of the rubber O-ring seal, oxygen gas and water component gas in the atmosphere that diffuses and permeates the inside of the rubber O-ring seal or high molecular weight gas released from the rubber O-ring seal itself It has become an obstacle to maintaining the environment within specifications. In other words, in order to achieve the specification, the design change to a metal seal for the rubber O-ring seal mounting part, or the amount of process gas introduced into the vacuum chamber, the amount of gas to be measured, or the gas in the vacuum chamber must be exhausted. There is a need, for example, to increase the pumping speed of the vacuum pump. Also, although it is not a vacuum device, even in the excimer laser that emits laser light by dissociation and combination of gas molecules in the chamber, how to suppress oxygen gas and water component gas entering the chamber is the key to stable laser output. has become an issue.

In order to solve such a problem, in Japanese Patent Application No. 2019-144034, a backup ring seal having a shape that fits inside the rubber 0-ring seal groove is arranged on the outer peripheral side or the inner peripheral side of the rubber 0-ring seal, and the chamber member The rubber 0-ring seal achieves the same sealing performance between the surface and the seal surface as before, and the amount of gas that diffuses and permeates inside the rubber 0-ring seal is reduced, making the backup ring seal more efficient than the rubber 0-ring seal. The material should have a sufficiently low gas permeability, and the surface condition should be such that the sealing performance between the surface and the surface of the chamber member is at least 10 to 30% of that of the rubber O-ring seal, and the rubber O-ring. The surface that comes into contact with the seal is in a surface state that can be sufficiently sealed, so that a composite seal in which both seals are in close contact is proposed to improve the sealing performance as a whole. In addition, Japanese Patent Application No. 2019-239715 proposes a backup ring seal shape that can be manufactured at low cost, and Japanese Patent Application No. 2020-100469 proposes a combined shape backup ring seal that can correspond to a rubber O-ring seal groove with a complicated shape. there is

Literature

Application Patent Document 1

Patent application 2019-144034

Application Patent Document 2

Patent application 2019-239715

Application Patent Document 3

Patent application 2020-100469

Application Patent Document 1 describes the key points of a backup ring seal for reducing the gas permeability of a rubber O-ring seal and illustrates an example of a backup ring seal that satisfies the requirements. not mentioned. Further, in Patent Document 2, a long backup ring seal that can be formed from a sheet material is proposed as a shape that can be manufactured at low cost, but it cannot correspond to an arc shape with a short curvature. Application Patent Document 3 proposes a combination type of backup ring seal for a rubber 0-ring seal having a complicated rubber 0-ring seal groove shape including a short curvature arc as a means of manufacturing at low cost. . However, these are based on the assumption that the cross-sectional shape of the seal groove is a general rectangular cross-sectional shape, and are used to prevent adhesion of the rubber O-ring seal when opening and closing the seal part in semiconductor manufacturing equipment. In the case of a dovetail groove cross-sectional shape, there is a problem that it is difficult to apply. The present invention is directed to a dovetail matched ultra-low gas permeability composite seal that overcomes this disadvantage.

In order to solve the above problems, the backup ring seal 100 shown in FIG. 1 of this patent cited from Japanese Patent Application No. 2019-144034, that is, the backup ring seal 100 having a shape that fits in the groove is placed on the outer peripheral side of the rubber O-ring seal 200. The sealing performance between the vacuum chamber surface 300 and the seal surface is achieved by the rubber O-ring seal 200 as before, and the backup ring seal 100 is used to reduce the amount of gas that diffuses and permeates the inside of the rubber O-ring seal 200. A surface that has a gas permeability sufficiently lower than that of the rubber O-ring seal 200 and that has a sealing performance between the surface and the vacuum chamber surface 300 that is at least 10 to 30% of that of the rubber O-ring seal 200. In addition, the surface that becomes the contact surface with the rubber O-ring seal 200 is in a surface state that can be sufficiently sealed, so that the seal performance is improved as a whole as a composite seal in which both seals are in close contact. If an ultra-low gas permeability composite seal that integrates a backup ring seal 100 and a rubber O-ring seal 200 for the purpose is used as an ultra-low gas permeability composite seal structure for a rectangular cross-sectional seal groove, as shown in FIG. The ultra-low gas permeability composite seal structure that conforms to the dovetail groove cross-sectional shape or the one-sided dovetail groove cross-sectional shape as shown in FIG. Alternatively, it must be an ultra-low gas permeability composite seal formed by combining the rubber O-ring seal 202 of FIG. 5 with a backup ring seal. In order to use the conventional rubber 0-ring as it is, the backup ring seal 101 in FIG. A relief recess 112 must be formed to match the shape. Furthermore, in the case of the single-sided groove of FIG. 7, it would be necessary to form a recess such as 122 on the outer periphery of the backup ring seal as well so that the backup ring seal is secured to the single-sided groove. Also, if the cross-sectional shape of the rubber 0-ring seal can be changed, like the rubber 0-ring seal 203 and the backup ring seal 103 shown in FIG. The dovetail groove compatible ultra-low gas permeability composite seal in which the rubber O-ring seal 203 and the rubber O-ring seal 203 are structurally integrated is the optimum structure for achieving both low cost and high performance.

Since the backup ring seal has a shape that fits in the conventional rubber O-ring seal groove, it can be applied without changing the design of the conventional seal structure, and the backup ring seal is placed outside the conventional rubber O-ring seal. By containing the, the part in contact with the gas in the chamber becomes the same rubber O-ring seal as before, and the reaction between the gas in the chamber and the surface of the rubber O-ring seal and the influence of the gas generated from that surface, etc. has the effect of greatly reducing the intrusion speed of oxygen gas and water component gas in the atmosphere into the chamber without any change from the conventional vacuum. It can be used as a dovetail matched ultra-low gas permeability composite seal for chambers or vacuum equipment such as deposition equipment.

In addition, it can be used as a dovetail groove-compatible ultra-low gas permeability composite seal for a sealed chamber of an excimer laser device, which is not a vacuum device, but which avoids intrusion of atmospheric oxygen gas, water component gas, etc. into the chamber.

In addition, as the amount of gas entering the rubber O-ring seal from the atmosphere decreases, the rate of release of gas generated from the rubber O-ring seal also decreases. Can be used as a dovetail groove compatible ultra-low gas permeability composite seal for pumps.

In addition, the backup ring seals 101, 102, 103 can be easily manufactured by cutting a sheet material into a long shape and carving it out with a tool that optimally forms concave portions of a certain shape in the long direction of the surface. Therefore, it becomes a backup ring seal for a dovetail groove compatible ultra-low gas permeability composite seal structure that can be mass-produced at low cost.

Mounting cross section of ultra-low gas permeability composite seal of patent application 2019-144034 Dovetail cross-sectional shape Single groove cross-sectional shape Rubber 0-ring seal mounting cross section for dovetail groove cross section Rubber 0-ring seal installation cross section for groove cross section shape with one side Mounting cross-sectional shape of dovetail groove compatible ultra-low gas permeability composite seal Mounting cross-sectional shape of ultra-low gas permeability composite seal compatible with one-sided groove Affordable Groove Fitting Ultra-Low Gas Permeability Composite Seal Mounted Cross-Sectional Shape

FIG. 1 shows a mounted cross section of an ultra-low gas permeability composite seal in which a backup ring seal of Japanese Patent Application No. 2019-144034 is inserted. This figure explains the operating mechanism of the ultra-low gas permeability composite seal that is the basis of the present invention. A solid line→path E is a gas path that passes between the surface of the backup ring seal 100 placed on the outside + the surface of the rubber O-ring seal 200 and the flange surface 300 . Here, even if the sealing effect of the surface of the backup ring seal 100 is inferior to that of the rubber O-ring seal 200, since the rubber O-ring seal 200 seals the path E, as a result Sealing performance does not deteriorate. On the other hand, it is important to reduce the amount of gas permeation along the dashed line→route F and dashed line→route G in FIG. Here, the path G passes through the backup ring seal 100 whose gas diffusion coefficient is 1/100 or less that of the rubber 0-ring seal 200 before it enters the surface of the rubber 0-ring seal 200. Even though the length is only 1/10 of the length of the rubber 0-ring seal 200, the number of gas intrusion to the atmosphere side surface of the rubber 0-ring seal 200 is less than 1/10 of the conventional case where it was exposed to atmospheric pressure. Become. In addition, even if the sealing performance of the surface of the backup ring seal 100 is about 10 to 30% of the sealing performance of the surface of the rubber O-ring seal 200, the path F runs between the surface of the backup ring seal 100 and the flange surface 300. Only the gas that has passed through reaches the atmosphere-side surface of the rubber O-ring seal 200, and most of that atmosphere-side surface is in close contact with the surface of the backup ring seal 100. The number of gases entering the side surface is much less than 1/10 of the conventional case where it is exposed to atmospheric pressure. Therefore, the present ultra-low gas permeability composite seal has a gas permeability of 1/10 or less that in the case of sealing with the rubber O-ring seal 200 alone.

2 is a cross-sectional view of a dovetail groove shape, and FIG. 3 is a cross-sectional view of a one-sided dovetail groove shape. Further, 201 in FIG. 4 is an example of a cross-sectional shape of a rubber O-ring seal for a dovetail groove shape, and 202 in FIG. 5 is an example of a cross-sectional shape of a rubber O-ring seal for a one-sided dovetail groove shape.

FIG. 6 is an installed cross-sectional view of one embodiment of the dovetail matched ultra-low gas permeability composite seal of the present invention. A concave portion 111 matching the shape of the rubber 0-ring seal 201 is formed in the backup ring seal 101 on the surface of the backup ring seal 101 on the rubber 0-ring seal side, and the rubber 0-ring seal and the backup ring seal are closely attached and integrated. This results in a dovetail compatible ultra-low gas permeability composite seal.

FIG. 7 is an installed cross-sectional view of one embodiment of a dovetail groove compatible ultra-low gas permeability composite seal that conforms to the single dovetail groove cross-sectional configuration of the present invention. A concave portion 112 matching the shape of the rubber 0-ring seal 202 is formed in the backup ring seal 102 on the surface of the backup ring seal 102 on the rubber 0-ring seal side, and the rubber 0-ring seal and the backup ring seal are closely attached and integrated. In addition, by forming a recess 122 on the surface of the backup ring seal 102 opposite to the rubber O-ring seal 202 so that the backup ring seal 102 is fixed in the dovetail groove, the dovetail groove compatible ultra-low gas permeability A dovetail compatible ultra-low gas permeability composite seal that prevents the composite seal from slipping out of the dovetail groove.

FIG. 8 is an installed cross-sectional view of one embodiment of the low cost dovetail groove matched ultra-low gas permeability composite seal of the present invention. The backup ring seal 103 is formed with a dovetail groove-like recess that matches the shape of the rubber 0-ring seal 203 on the surface of the backup ring seal 103 on the rubber 0-ring seal 203 side, and the rubber 0-ring seal 203 and the backup ring seal are formed. 103 is closely attached and integrated, and the backup ring seal 103 does not come off from the dovetail groove.

When performing upgrade maintenance for the purpose of improving the performance of used film deposition equipment, by using the dovetail groove compatible ultra-low gas permeability composite seal shown in Figs. Without changing to a vacuum pump, it is possible to reduce the concentration of atmospheric component gases such as oxygen gas and water component gas that enter the vacuum chamber, albeit in very small amounts. In addition, it is possible to improve the sealing performance of a rubber O-ring seal between a ceramic electrode and an aluminum member where a metal seal could not be used even if desired, to almost the same level as that of a metal seal.

By using the dovetail groove compatible ultra-low gas permeability composite seal shown in FIGS. The reaction between the gas and the rubber O-ring seal surface and the influence of the gas generated from that surface are the same as before, and the intrusion of oxygen gas and water component gas in the atmosphere into the chamber is greatly reduced. It can be used as a dovetail-groove compatible ultra-low gas permeability composite seal for vacuum chambers that do not tolerate increases in oxygen gas concentration and water component gas concentration in the chamber, such as film deposition equipment.

By utilizing the dovetail matched ultra-low gas permeability composite seals shown in FIGS. Since the intrusion rate of gases such as oxygen gas and water component gas can be reduced, an excimer laser device in which the frequency of gas exchange in the chamber is reduced can be realized.

In addition, since the rate of outgassing generated from the rubber O-ring seal is also reduced, it can be used as a dovetail-matched ultra-low gas permeability composite seal for analyzers and their vacuum pumps that dislike the intrusion of high-molecular-weight gases.

100, 101, 102, 103 backup ring seals 111, 112, 113 backup ring seal recesses 200, 201, 202, 203 to match the shape of the rubber O-ring seal rubber O-ring seal 300 flange surface

Claims (8)

A back-up ring seal with a constant-shaped concave portion along the length direction of the surface of a long material with a constant width and a constant thickness that can be closely attached, and a rubber O-ring seal with a convex portion that adheres to the concave portion are integrated. Dovetail Groove Fit Ultra-Low Gas Permeability Composite Seal A back-up ring seal with a constant-shaped concave portion along the length direction on both sides of a long material with a constant width and a constant thickness that can be closely attached, and a rubber O-ring seal with a convex portion that is in close contact with the concave portion on one side. Dovetail compatible ultra-low gas permeability composite seal In the backup ring seal in close contact with the rubber O-ring seal according to claim 1, the dovetail groove compatible ultra-low gas permeability composite seal has a recess shape of the backup ring seal and a groove shape A film forming apparatus using the dovetail groove compatible ultra-low gas permeability composite seal according to claim 1, claim 2, or claim 3 An excimer laser device using the dovetail groove compatible ultra-low gas permeability composite seal according to claim 1, claim 2, or claim 3 An analyzer using the dovetail groove compatible ultra-low gas permeability composite seal according to claim 1, claim 2, or claim 3 A vacuum chamber using the dovetail groove compatible ultra-low gas permeability composite seal according to claim 1, claim 2, or claim 3 A sealed chamber using the dovetail groove compatible ultra-low gas permeability composite seal according to claim 1, claim 2, or claim 3.

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