Vacuum chamber seal structure

Abstract

The application provides a sealing structure for a vacuum chamber, a plasma reaction chamber and a microwave plasma chemical vapor deposition device. The vacuum chamber comprises a base structure extending into the cavity from the outside, the base structure can rotate around an axis and move up and down, the sealing structure is used for dynamic sealing between the base structure and the cavity wall, the sealing structure at least comprises a first sealing ring arranged between the base structure and the cavity wall, the surface of the first sealing ring is coated with a lubricant to form a wet seal, and an adsorptive filler is arranged on the vacuum end side of the first sealing ring. The sealing structure for the vacuum chamber can improve the sealing performance of the vacuum chamber, prolong the service life of the sealing material, and reduce the pollution caused by the sealing structure.

Description

Technical Field

[0001] This invention relates to the field of vacuum microelectronics technology, and more particularly to a sealing structure for a vacuum chamber, as well as a plasma reaction chamber and a microwave plasma chemical vapor deposition apparatus employing the sealing structure. Background Technology

[0002] Vacuum equipment in modern industry must possess excellent sealing performance, typically achieved by pressing a soft material between two metal sealing surfaces within the sealing structure. The deformation of this soft material fills the gaps between the metal surfaces, thus achieving a seal. If the two metal sealing surfaces need to move frequently, to ensure simultaneous sealing, the soft material is usually a rubber O-ring. The rubber deforms under the pressure of the two metal sealing surfaces, thereby achieving a vacuum seal.

[0003] In vacuum equipment used in the field of vacuum microelectronics, the base is required to rotate and move up and down around its central axis. This necessitates maintaining a tight seal while the base moves. Currently, O-rings are typically used on the base support rod for sealing. If the O-ring surface is not coated with any other material, the friction between the O-ring and the metal sealing surface is dry friction during base movement. This results in a high coefficient of friction, causing the O-ring surface to wear easily and shortening its lifespan. To improve this, vacuum grease can be applied to the O-ring surface to form a very thin liquid layer, providing lubrication. This liquid layer also better fills the gap between the O-ring and the metal sealing surface, effectively preventing air and other impurities from entering the vacuum chamber. However, due to the evaporation of the lubricant, vacuum contamination is inevitable.

[0004] In order to overcome the above-mentioned defects of the existing technology, there is an urgent need in the field for a sealing structure for vacuum chambers that can improve the sealing performance of vacuum chambers, extend the service life of sealing materials, and reduce the pollution caused by the sealing structure. Summary of the Invention

[0005] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form to prepare for the more detailed descriptions that follow.

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a sealing structure for a vacuum chamber, which can improve the sealing performance of the vacuum chamber, extend the service life of the sealing material, and reduce the pollution caused by the sealing structure.

[0007] Specifically, according to the first aspect of the present invention, the sealing structure for a vacuum chamber includes a base structure extending into the chamber from the outside, the base structure being rotatable about an axis and capable of vertical movement, the sealing structure being used for dynamic sealing between the base structure and the chamber wall, the sealing structure including at least a first sealing ring disposed between the base structure and the chamber wall, the surface of the first sealing ring being coated with a lubricant to form a wet seal, and an absorbent filler being provided on the vacuum end side of the first sealing ring.

[0008] Preferably, in one embodiment of the present invention, a second sealing ring is further disposed between the base structure and the cavity wall. The second sealing ring is closer to the vacuum end than the first sealing ring. The surface of the second sealing ring is not coated with lubricant to form a dry seal. The absorbent filler is located between the first sealing ring and the second sealing ring.

[0009] Preferably, in one embodiment of the present invention, the absorbent filler comprises a filamentous filler.

[0010] Preferably, in one embodiment of the present invention, a plurality of first sealing rings and / or a plurality of second sealing rings are included.

[0011] Preferably, in one embodiment of the present invention, the first sealing ring and the second sealing ring comprise O-rings.

[0012] Preferably, in one embodiment of the present invention, the lubricant comprises vacuum silicone grease.

[0013] Preferably, in one embodiment of the present invention, the substrate structure includes a substrate stage for CVD diamond growth and a substrate stage support rod, and the sealing structure is used for dynamic sealing between the substrate stage support rod and the cavity wall.

[0014] Preferably, in one embodiment of the present invention, the portion of the cavity wall that contacts the substrate stage support rod is sleeved around the substrate stage support rod in the form of a bushing, and the sealing structure forms a dynamic seal between the substrate stage support rod and the bushing.

[0015] Furthermore, according to a second aspect of the present invention, a plasma reaction chamber is provided, comprising a vacuum chamber, the vacuum chamber including a base structure extending into the chamber from the outside, the base structure being rotatable about an axis and capable of vertical movement, and the base structure and the chamber wall being dynamically sealed by a sealing structure as described in any of the above embodiments.

[0016] Furthermore, according to a third aspect of the present invention, a microwave plasma chemical vapor deposition apparatus is provided, comprising a microwave system, a vacuum system, a gas supply system, and the plasma reaction chamber provided in the second aspect of the present invention. Attached Figure Description

[0017] The above-described features and advantages of the present invention will be better understood after reading the following detailed description of embodiments of the present disclosure in conjunction with the accompanying drawings. In the drawings, components are not necessarily drawn to scale, and components having similar related characteristics or features may have the same or similar reference numerals.

[0018] Figure 1 A schematic diagram of a vacuum plasma reaction chamber is shown; and

[0019] Figure 2 A schematic diagram of a sealing structure for a vacuum chamber according to an embodiment of the present invention is shown.

[0020] For clarity, a brief explanation of the reference numerals in the accompanying drawings is provided below:

[0021] PB Plasma Sphere

[0022] 100 plasma reaction chamber

[0023] 110 base structure

[0024] 200 vacuum chamber

[0025] 210 base structure

[0026] 211 substrate stage

[0027] 212 substrate stage support rod

[0028] 220 cavity wall

[0029] 221 bushing

[0030] 300 sealing structure

[0031] 310 First sealing ring

[0032] 320 absorbent filler

[0033] 330 Second Sealing Ring Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should be noted that the aspects described below with reference to the accompanying drawings and specific embodiments are merely exemplary and should not be construed as limiting the scope of protection of the present invention in any way.

[0035] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0036] Furthermore, the terms "upper," "lower," "left," "right," "top," "bottom," "horizontal," and "vertical" used in the following description should be understood as the orientations shown in the relevant paragraphs and accompanying drawings. These relative terms are for illustrative purposes only and do not imply that the described apparatus must be manufactured or operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0037] It is understood that although terms such as "first," "second," and "third" may be used herein to describe various components, regions, layers, and / or parts, these components, regions, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers, and / or parts. Therefore, the first components, regions, layers, and / or parts discussed below may be referred to as second components, regions, layers, and / or parts without departing from some embodiments of the present invention.

[0038] Figure 1 A schematic diagram of a plasma reaction chamber 100 is shown, which includes a base structure 110. Microwave plasma chemical vapor deposition apparatuses generally include a microwave system, a vacuum system, a gas supply system, and other components such as... Figure 1 The plasma reaction chamber 100 is shown. (As shown) Figure 1 As shown, a circular seed crystal with a certain thickness for diamond growth is placed on the upper surface of the substrate. Microwaves generated by the microwave system enter the plasma reaction chamber 100, exciting the gas supplied by the gas supply system above the substrate structure to generate a plasma ball PB. The plasma ball PB is closely attached to the seed crystal surface. By adjusting different reaction gases and process parameters, CVD diamonds can be grown on the surfaces of seed crystals A and B.

[0039] The pedestal structure 110 within the plasma reaction chamber 100 is generally rotatable around its central axis and can move vertically relative to the reaction chamber. Since the plasma reaction chamber 100 needs to maintain a vacuum, it is required to maintain a sealing effect while the pedestal structure 110 is moving.

[0040] As mentioned above, in existing technologies, O-rings are typically used on the base support rod for sealing. If the surface of the O-ring is not coated with any other substance, the friction between the O-ring and the metal sealing surface is dry friction during base movement. In this case, the coefficient of friction is high, the O-ring surface is easily worn, and the service life of the O-ring is shortened. If vacuum grease is applied to the surface of the O-ring to form a very thin liquid layer for lubrication, the evaporation of this lubricant will inevitably cause vacuum contamination.

[0041] In order to overcome the above-mentioned defects of the prior art, the present invention provides a sealing structure for a vacuum chamber, which can improve the sealing performance of the vacuum chamber, extend the service life of the sealing material, and reduce the pollution caused by the sealing structure itself.

[0042] Please refer to Figure 2 , Figure 2 A schematic diagram of a sealing structure 300 for a vacuum chamber according to an embodiment of the present invention is shown. This vacuum chamber can be used in microwave plasma reaction chambers; in other embodiments, the vacuum chamber can also be used in any application requiring a vacuum environment.

[0043] like Figure 1 As shown, the vacuum chamber 200 includes a cavity wall 220, the interior of which is a vacuum chamber is enclosed by the cavity wall 220, and the exterior is an atmospheric pressure region outside the vacuum chamber. The vacuum chamber 200 has an axisymmetric structure, and a base structure 210 may be provided at the central axis of the vacuum chamber 200. The base structure 210 can extend into the vacuum chamber from the outside, and during operation, the base structure 210 can rotate around its axis and move up and down. In order to maintain the vacuum state of the chamber, a sealing structure 300 is required to achieve a dynamic seal between the base structure 210 and the cavity wall 220.

[0044] exist Figure 2 In the illustrated embodiment, the substrate structure 210 includes a substrate stage 211 for CVD diamond growth and a substrate stage support rod 212. The portion of the cavity wall 220 that contacts the substrate stage support rod 212 is fitted around the substrate stage support rod 212 in the form of a bushing 221, thereby forming a bushing structure between this portion of the cavity wall 220 and the substrate stage support rod 212. The sealing structure 100 can form a dynamic seal between the substrate stage support rod 212 and the bushing 221.

[0045] According to one aspect of the invention, the sealing structure 300 may include at least a first sealing ring 310 disposed between the base structure 210 and the cavity wall 220. Figure 2In the illustrated embodiment, the first sealing ring 310 can be fitted onto the substrate stage support rod 212, thereby being positioned between the substrate stage support rod 212 and the bushing 221 to achieve a dynamic seal between the substrate stage support rod 212 and the bushing 221. In this invention, the surface of the first sealing ring 310 can be coated with a lubricant, such as vacuum silicone grease, to form a wet seal. The lubricant can form a very thin liquid layer on the surface of the first sealing ring 310 to provide lubrication and reduce friction. This reduces wear on the sealing ring, thereby increasing its lifespan. Furthermore, the liquid layer can better fill the gap between the sealing ring and the bushing, improving the sealing performance.

[0046] Specifically, an adsorbent filler 320 is provided on the vacuum end side of the first sealing ring 310 (viewed from above the first sealing ring 310 in the figure). By providing the adsorbent filler 320, molecules volatilized from the wet seal formed by the first sealing ring 310 are adsorbed onto the surface of the adsorbent filler 320. In one embodiment, the adsorbent filler 320 can be a filler with a high specific surface area, preferably a filamentous filler such as natural flax fibers, artificial nylon fibers, etc. More preferably, the surface of these filamentous materials can be treated to obtain better adsorption effects, and better suited for adsorbing large quantities of lubricating oil molecules used for wet sealing. Because the lubricant volatiles are absorbed, contamination of the vacuum chamber is avoided.

[0047] In a preferred embodiment, the sealing structure 300 may further include a second sealing ring 330 disposed between the base structure 210 and the cavity wall 220. Figure 2 In the illustrated embodiment, the second sealing ring 330 can be fitted onto the substrate stage support rod 212, thereby being positioned between the substrate stage support rod 212 and the bushing 221 to achieve a second dynamic seal between the substrate stage support rod 212 and the bushing 221. The second sealing ring 330 is closer to the vacuum end than the first sealing ring 310 (viewed from above the first sealing ring 310 in the figure), and the surface of the second sealing ring 330 is not coated with lubricant to form a dry seal. Here, the absorbent filler 320 is located between the first sealing ring 310 and the second sealing ring 330. By providing the second sealing ring 330, the sealing structure 300 can prevent the further diffusion and migration of volatiles not adsorbed by the absorbent filler 320 into the vacuum chamber. Simultaneously, the movement area of ​​the absorbent filler 320 can be controlled by the second sealing ring 330.

[0048] The first sealing ring 310 and the second sealing ring 330 are preferably O-rings. In a non-limiting embodiment, the sealing structure 300 for the vacuum chamber 200 may include a plurality of first sealing rings and a plurality of second sealing rings.

[0049] In summary, the sealing structure for vacuum chambers provided by this invention can improve the sealing effect of vacuum chambers, extend the service life of sealing rings, and adsorb substances volatilized by the sealing structure itself, thus preventing contamination of the vacuum chamber by the volatilized substances.

[0050] According to another aspect of the present invention, the sealing structure for a vacuum chamber described above can be applied to a plasma reaction chamber. The plasma reaction chamber may include a vacuum chamber, which may include a base structure extending into the chamber from the outside. The base structure is rotatable about an axis and can move up and down. A dynamic seal can be achieved between the base structure and the chamber wall through the sealing structure for a vacuum chamber provided in the first aspect of the present invention.

[0051] Furthermore, according to a third aspect of the present invention, a microwave plasma chemical vapor deposition apparatus is provided, which may include a microwave system, a vacuum system, a gas supply system, and a plasma reaction chamber provided according to a second aspect of the present invention.

[0052] It should be understood that this specification is not intended to interpret or limit the scope or meaning of the claims. Furthermore, as can be seen in the foregoing detailed description, various features are combined in a single embodiment for the purpose of streamlining this disclosure. This approach of the disclosure should not be construed as reflecting the aim of the claimed embodiments requiring more features than expressly listed in each claim. Rather, as reflected in the appended claims, the inventive subject matter lies in fewer than all features of a single disclosed embodiment. Therefore, the appended claims are hereby incorporated into the detailed description, wherein each claim is considered independently as a separate embodiment.

[0053] The prior description of this disclosure is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not intended to be limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sealing structure for a vacuum chamber, the vacuum chamber including a base structure extending into the chamber from the outside, the base structure being rotatable about an axis and capable of vertical movement, the sealing structure being used for dynamic sealing between the base structure and the chamber wall, the sealing structure including at least a first sealing ring disposed between the base structure and the chamber wall, the surface of the first sealing ring being coated with a lubricant to form a wet seal, an absorbent filler being provided on the vacuum end side of the first sealing ring, the sealing structure further including a second sealing ring disposed between the base structure and the chamber wall, the second sealing ring being closer to the vacuum end than the first sealing ring, the surface of the second sealing ring not being coated with a lubricant to form a dry seal, the absorbent filler being located between the first sealing ring and the second sealing ring.

2. The sealing structure as claimed in claim 1, characterized in that, The absorbent filler includes filamentous fillers.

3. The sealing structure as claimed in claim 1, characterized in that, It includes multiple first sealing rings and / or multiple second sealing rings.

4. The sealing structure as claimed in claim 1, characterized in that, The first sealing ring and the second sealing ring include O-rings.

5. The sealing structure as claimed in claim 1, characterized in that, The lubricant includes vacuum silicone grease.

6. The sealing structure as claimed in claim 1, characterized in that, The substrate structure includes a substrate stage and a substrate stage support rod for CVD diamond growth, and the sealing structure is used for dynamic sealing between the substrate stage support rod and the cavity wall.

7. The sealing structure as claimed in claim 6, characterized in that, The portion of the cavity wall that contacts the substrate stage support rod is sleeved around the substrate stage support rod in the form of a bushing, and the sealing structure forms a dynamic seal between the substrate stage support rod and the bushing.

8. A plasma reaction chamber, comprising a vacuum chamber, the vacuum chamber including a base structure extending into the chamber from the outside, the base structure being rotatable about an axis and capable of vertical movement, the base structure and the chamber wall being dynamically sealed by a sealing structure as described in any one of claims 1-7.

9. A microwave plasma chemical vapor deposition apparatus, characterized in that, It includes a microwave system, a vacuum system, a gas supply system, and a plasma reaction chamber as described in claim 8.

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