A plasma reaction chamber and microwave plasma chemical vapor deposition apparatus

Abstract

The application provides a kind of plasma reaction chamber and microwave plasma chemical vapor deposition device.The plasma reaction chamber includes: vacuum chamber, including the base structure from outside into cavity in vacuum chamber, microwave window is positioned above the base structure in the top of vacuum chamber, and the vacuum chamber includes first flow uniform ring and / or second flow uniform ring, wherein, first flow uniform ring is positioned around microwave window in the top of vacuum chamber, and a plurality of first gas outlet holes for supplying reaction gas into vacuum chamber are provided on first flow uniform ring, the direction of a plurality of first gas outlet holes is arranged so that the reaction gas sprayed from first gas outlet hole forms gas curtain on the lower surface of the microwave window, and second flow uniform ring is arranged around the side wall of the vacuum chamber, and a plurality of vertically oriented second gas outlet holes for supplying reaction gas into the vacuum chamber are provided on the second flow uniform ring, so that the reaction gas sprayed from the second gas outlet hole forms a gas curtain on the inner surface of the side wall of the vacuum chamber.

Description

Technical Field

[0001] This invention relates to the field of plasma technology, and more particularly to a plasma reaction chamber and a microwave plasma chemical vapor deposition apparatus. Background Technology

[0002] Microwave plasma chemical vapor deposition (MPCVD) equipment generally includes a microwave system, a vacuum system, a gas supply system, and a plasma reaction chamber. Taking the preparation of diamond films as an example, the microwaves generated by the microwave system enter the plasma reaction chamber. The gas supplied by the gas supply system is excited above the substrate stage in the plasma reaction chamber to generate plasma spheres. The plasma spheres adhere closely to the surface of the film-forming substrate material to deposit and form a diamond film.

[0003] In plasma reaction processes, such as the preparation of diamond films, reactant gases like methane and hydrogen decompose into various active groups under the influence of plasma, depositing onto the substrate surface to form a diamond film. During this process, due to the excitation, activation, diffusion, and deposition of gases within the vacuum reaction chamber, some solid deposits also accumulate on the inner walls of the vacuum chamber and adhere to the surface of the microwave window. Furthermore, as the deposition time increases, the thickness of the deposits continuously increases, eventually potentially leading to fracture under internal stress. The resulting fragments fall onto the substrate surface, forming contaminants and thus affecting the normal growth of the diamond.

[0004] To overcome the aforementioned deficiencies in the existing technology, there is an urgent need in the field for a plasma reaction chamber and a microwave plasma chemical vapor deposition device that can protect the inner wall of the vacuum chamber and the surface of the microwave window during the plasma reaction process, thereby preventing the deposition of solid deposits and the increase in the thickness of solid deposits. 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] To overcome the aforementioned deficiencies in the prior art, the present invention provides a plasma reaction chamber and a microwave plasma chemical vapor deposition apparatus, which can protect the inner wall of the vacuum chamber and the surface of the microwave window during the plasma reaction process, thereby preventing the deposition of solid deposits and the increase in the thickness of solid deposits.

[0007] Specifically, the plasma reaction chamber provided according to the first aspect of the present invention includes: a vacuum chamber, the vacuum chamber including a base structure extending into the chamber from the outside, a microwave window provided above the base structure at the top of the vacuum chamber for allowing microwaves to enter the vacuum chamber, the vacuum chamber including a first flow equalization ring and / or a second flow equalization ring, wherein the first flow equalization ring is disposed at the top of the vacuum chamber surrounding the microwave window, the first flow equalization ring is provided with a plurality of first gas outlets for supplying reactive gas into the vacuum chamber, the orientation of the plurality of first gas outlets is configured such that the reactive gas ejected from the first gas outlets forms a gas curtain on the lower surface of the microwave window, wherein the second flow equalization ring is disposed around the side wall of the vacuum chamber, the second flow equalization ring is provided with a plurality of vertically oriented second gas outlets for supplying reactive gas into the vacuum chamber, such that the reactive gas ejected from the second gas outlets forms a gas curtain on the inner surface of the side wall of the vacuum chamber.

[0008] Preferably, in one embodiment of the present invention, the vacuum chamber includes the first flow equalization ring, and the orientation of the plurality of first air outlets is set to face the center of the microwave window.

[0009] Preferably, in one embodiment of the present invention, the vacuum chamber includes a first flow equalization ring, which is disposed along the lower edge of the microwave window and closely abuts the lower surface of the microwave window.

[0010] Preferably, in one embodiment of the present invention, the vacuum chamber includes the first flow equalization ring, and the plurality of first air outlets are centrally symmetrically distributed.

[0011] Preferably, in one embodiment of the present invention, the vacuum chamber includes the second flow equalization ring, and the second vent includes both upward-facing and downward-facing vents.

[0012] Preferably, in one embodiment of the present invention, the second flow equalization ring is disposed close to the side wall at the top of the vacuum chamber.

[0013] Preferably, in one embodiment of the present invention, a metal baffle is provided at the bottom of the vacuum chamber, and the baffle forms an annular gap with the side wall of the vacuum chamber, through which the reaction gas is drawn to the outside of the vacuum chamber by a vacuum pump.

[0014] Furthermore, the microwave plasma chemical vapor deposition apparatus provided according to the second aspect of the present invention includes a microwave system, a vacuum system, a gas supply system, and a plasma reaction chamber provided in any of the above embodiments.

[0015] Preferably, in one embodiment of the present invention, a metal baffle is provided at the bottom of the vacuum chamber, the baffle and the side wall of the vacuum chamber form an annular gap, and the gas supply system further includes a vacuum pump for extracting the reaction gas from the vacuum chamber through the annular gap.

[0016] Preferably, in one embodiment of the present invention, the vacuum pump includes a wet vacuum pump connected to the vacuum chamber via a first flow control valve and a dry vacuum pump connected to the vacuum chamber via a second flow control valve. The dry vacuum pump extracts gas from the vacuum chamber and circulates it back into the vacuum chamber through a second flow equalization ring. 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 microwave plasma chemical vapor deposition apparatus according to some embodiments of the present invention is shown; and

[0019] Figure 2 A schematic diagram of the top surface of a vacuum chamber provided according to some embodiments of the present invention is shown.

[0020] Figure Labels

[0021] 100 Microwave Plasma Chemical Vapor Deposition Apparatus;

[0022] 110 Plasma Reaction Chamber;

[0023] 111, 200 Vacuum chambers;

[0024] 112. Base structure;

[0025] 113, 201 Microwave window;

[0026] 114, 210 First flow equalization ring;

[0027] 115, 119 Reaction gases;

[0028] Gas supply pipelines 116 and 118;

[0029] 117, 220 Second flow equalization ring;

[0030] 120 Microwave System;

[0031] 130 Plasma Spheres;

[0032] 140 baffle;

[0033] 151 First flow control valve;

[0034] 152 Wet vacuum pump;

[0035] 153 Second flow control valve;

[0036] 154 Dry vacuum pump; and

[0037] 202 Top surface. Detailed Implementation

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] As described above, during plasma reaction processes, such as the preparation of diamond films, reactant gases like methane and hydrogen decompose into various active groups under the influence of plasma, depositing onto the substrate surface to form a diamond film. During this process, due to the excitation, activation, diffusion, and deposition of gases within the vacuum reaction chamber, some solid deposits also accumulate on the inner walls of the vacuum chamber and adhere to the surface of the microwave window. Furthermore, as the deposition time increases, the thickness of the deposits continuously increases, eventually potentially leading to fracture under internal stress. The resulting fragments fall onto the substrate surface, forming contaminants and thus affecting the normal growth of the diamond.

[0043] To overcome the aforementioned deficiencies in the prior art, the present invention provides a plasma reaction chamber and a microwave plasma chemical vapor deposition apparatus, which can protect the inner wall of the vacuum chamber and the surface of the microwave window during the plasma reaction process, thereby preventing the deposition of solid deposits and the increase in the thickness of solid deposits.

[0044] Please refer to Figure 1 , Figure 1 A schematic diagram of a microwave plasma chemical vapor deposition apparatus provided according to some embodiments of the present invention is shown.

[0045] The microwave plasma chemical vapor deposition apparatus provided by this invention includes a microwave system, a vacuum system, a gas supply system, and a plasma reaction chamber. For example... Figure 1 As shown, the microwave plasma chemical vapor deposition apparatus 100 includes a plasma reaction chamber 110. The plasma reaction chamber 110 may include a vacuum chamber 111, and the vacuum chamber 111 may also contain a base structure 112 extending into the chamber from the outside. The base structure 112 may be located at the central axis of the plasma reaction chamber 110. A microwave window 113 may also be provided at the top of the vacuum chamber 111 and above the base structure 112. The microwave window 113 may be circular.

[0046] Above the plasma reaction chamber 110 may be a microwave system 120. The microwave system 120 is used to emit microwaves that pass through the microwave window 113 at the top of the vacuum chamber 111, allowing the microwaves to enter the vacuum chamber 111 and excite the reactive gas in the vacuum chamber 111 to form plasma spheres 130, thereby depositing a diamond film on the substrate stage surface of the abutment structure 112.

[0047] The top of the vacuum chamber 111 is provided with a first flow equalization ring 114 surrounding the microwave window 113. The first flow equalization ring 114 can be connected to the gas supply pipe 116 of the gas supply system. The gas supply system introduces the reaction gas 115 into the first flow equalization ring 114 through the gas supply pipe 116, and the first flow equalization ring 114 then supplies the reaction gas 115 into the vacuum chamber 111.

[0048] The first flow equalization ring 114 is provided with multiple first air outlets, the orientation of which can vary, as long as the reactant gas 115 ejected from the first air outlets can form an air curtain on the lower surface of the microwave window 113. For example, the first flow equalization ring 114 can have multiple first air outlets on the left side, ejecting reactant gas 115 to the right to form an air curtain, or the orientation of the first flow equalization ring 114 can be at a certain angle to the horizontal plane parallel to the microwave window 113, and so on. In addition, the multiple first air outlets can also be centrally symmetrically distributed to ensure the stability of the airflow field of the formed air curtain.

[0049] Preferably, the orientation of the plurality of first vent holes can be set towards the center of the microwave window 113 (e.g., Figure 1 (As indicated by the middle arrow). At this time, the reactive gas 115 ejected from the first vent will converge at the center of the microwave window 113 and then diffuse across the surface of the substrate stage in the lower abutment structure 112. If the abutment structure 112 is located at the central axis, the reactive gas 115 will flow more across the substrate stage surface near the central axis. This airflow pattern allows more reactive gas 115 to flow through the center of the substrate stage, improving the efficiency of diamond film deposition.

[0050] Here, the reaction gas can be a strictly fixed gas used for diamond growth, such as a gas mixture of H2 / CH4 / CO2 in a fixed ratio. In this reaction gas system, carbon is in a supersaturated state, so it is often used for diamond growth.

[0051] More preferably, the first flow equalization ring 114 can be disposed along the lower edge of the microwave window 113. When the microwave window 113 is circular, the first flow equalization ring 114 is an annular flow equalization ring. In this case, the first flow equalization ring 114 can be closely attached to the lower surface of the microwave window 113, making the gap between the formed gas curtain and the microwave window 113 smaller, and reducing the deposition of pollutants generated during the reaction on the surface of the microwave window 113.

[0052] In another embodiment, a second flow equalization ring 117 may be provided on the side wall of the vacuum chamber 111. The second flow equalization ring 117 surrounds the side wall and is connected to the gas supply pipe 118 of the gas supply system. The gas supply system introduces the reaction gas 119 into the second flow equalization ring 117 through the gas supply pipe 118.

[0053] The reactive gas 119 in gas supply pipe 118 has the same composition as the reactive gas 115 in gas supply pipe 116.

[0054] The second flow equalization ring 117 is provided with a plurality of vertically oriented second gas outlets. The second flow equalization ring 117 supplies reaction gas 119 into the vacuum chamber 111 through the plurality of second gas outlets, so that the reaction gas 119 ejected from the second gas outlets forms a gas curtain on the inner surface of the side wall of the vacuum chamber 111.

[0055] exist Figure 1 In the illustrated embodiment, the second flow equalization ring 117 is located below the first flow equalization ring 114 and can be disposed close to the top side wall of the vacuum chamber 111. In another embodiment, the second flow equalization ring 117 may also be on the same horizontal plane as the first flow equalization ring.

[0056] Please refer to Figure 2 , Figure 2 A schematic diagram of the top surface of a vacuum chamber provided according to some embodiments of the present invention is shown.

[0057] like Figure 2 As shown, in a cylindrical vacuum chamber 200, the diameter of the circular microwave window 201 is relatively small, while the diameter of the top surface 202 of the vacuum chamber 200 is relatively large. Therefore, the diameters of the first flow equalization ring 210 and the second flow equalization ring 220 are also different. The first flow equalization ring 210 is arranged along the lower edge of the microwave window 201, and its diameter matches the diameter of the microwave window 201; the second flow equalization ring 220 surrounds the side wall of the vacuum chamber 200, and its diameter matches the diameter of the top surface 202.

[0058] The second vent can spray air downwards only, or it can be like... Figure 1 The diagram shows a second air outlet that faces upwards and downwards. Optionally, the second flow equalization ring 117 may also be disposed in the middle of the vacuum chamber 111, forming an air curtain on the inner surface of the side wall of the vacuum chamber 111 through the upward and downward air outlets.

[0059] Please continue to refer to this. Figure 1 The gas supply system of the microwave plasma chemical vapor deposition apparatus 100 may also include a vacuum pump. This vacuum pump is connected to the vacuum chamber 111 via the bottom of the plasma reaction chamber 110 and can be used to extract gas from the vacuum chamber.

[0060] Preferably, a metal baffle 140 may be provided at the bottom of the vacuum chamber 111. The baffle 140 forms an annular gap with the side wall of the vacuum chamber 111, and the reaction gas in the vacuum chamber can be drawn out of the vacuum chamber 111 by the vacuum pump through the annular gap.

[0061] At this point, after the second flow equalization ring 117 ejects the reactant gas 119, the reactant gas 119 will gradually diffuse downwards along the inner wall surface of the vacuum chamber 111, and then through the annular gap formed by the metal baffle 140 and the side wall of the vacuum chamber 111, and finally be drawn away by the vacuum pump. By evacuating through the vacuum pump, the gas flow can be further guided to diffuse downwards.

[0062] like Figure 1As shown, the vacuum pump of the gas supply system may further include a wet vacuum pump 152 connected to the vacuum chamber 111 via a first flow control valve 151, for discharging the pumped gas to the outside. This wet vacuum pump 152 may be a rotary vane oil-sealed mechanical pump, etc.

[0063] More preferably, the vacuum pump may also include a dry vacuum pump 154 ​​connected to the vacuum chamber 111 via a second flow control valve 153. After the dry vacuum pump 154 ​​extracts the gas from the vacuum chamber 111, it circulates the gas back into the vacuum chamber 111 through a second flow equalization ring 117. The dry vacuum pump 154 ​​may be a screw pump or the like.

[0064] The first flow control valve 151 and the second flow control valve 153 can control the gas flow rate. By adjusting the flow control valves, a small portion of the gas can be discharged to the external atmospheric pressure environment through the wet vacuum pump 152, while most of the gas is circulated to the second flow equalization ring 117 through the dry vacuum pump 154.

[0065] At this time, by recirculating the reaction gas in the vacuum chamber 111 back into the vacuum chamber 111, the amount of reaction gas 119 used in the second flow equalization ring 117 can be greatly reduced. At the same time, the utilization efficiency of the reaction gas 119 can be improved and the consumption of the reaction gas 119 can be reduced.

[0066] In summary, the plasma reaction chamber and the microwave plasma chemical vapor deposition apparatus containing the plasma reaction chamber provided by the present invention can protect the inner wall of the vacuum chamber and the surface of the microwave window during the plasma reaction process, avoid the deposition of solid deposits and the increase of solid deposit thickness, and at the same time significantly reduce the consumption of reaction gases.

[0067] 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 plasma reaction chamber, comprising: A vacuum chamber includes a base structure extending into the chamber from the outside. A microwave window is located above the base structure at the top of the vacuum chamber to allow microwaves to enter. The vacuum chamber includes a first flow equalization ring and a second flow equalization ring. The first flow equalization ring is disposed at the top of the vacuum chamber surrounding the microwave window. The first flow equalization ring has multiple first vent holes for supplying reactant gas into the vacuum chamber. The orientation of the multiple first vent holes is configured such that the reactant gas ejected from the first vent holes forms a gas curtain on the lower surface of the microwave window. The orientation of the multiple first vent holes is set towards the center of the microwave window. The second flow equalization ring is disposed around the side wall of the vacuum chamber, and the second flow equalization ring is provided with a plurality of vertically oriented second air outlets for supplying reaction gas into the vacuum chamber, so that the reaction gas ejected from the second air outlets forms an air curtain on the inner surface of the side wall of the vacuum chamber.

2. The plasma reaction chamber as described in claim 1, characterized in that, The vacuum chamber includes the first flow equalization ring, which is disposed along the lower edge of the microwave window and closely attached to the lower surface of the microwave window.

3. The plasma reaction chamber as described in claim 1, characterized in that, The vacuum chamber includes the first flow equalization ring, and the plurality of first air outlets are centrally symmetrically distributed.

4. The plasma reaction chamber as described in claim 1, characterized in that, The vacuum chamber includes the second flow equalization ring, and the second vent includes both upward-facing and downward-facing vents.

5. The plasma reaction chamber as described in claim 4, characterized in that, The second flow equalization ring is disposed close to the side wall at the top of the vacuum chamber.

6. The plasma reaction chamber as described in claim 1, characterized in that, The bottom of the vacuum chamber is provided with a metal baffle, which forms an annular gap with the side wall of the vacuum chamber. The reaction gas is drawn out of the vacuum chamber by the vacuum pump through the annular gap.

7. 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 any one of claims 1 to 6.

8. The microwave plasma chemical vapor deposition apparatus as described in claim 7, characterized in that, The bottom of the vacuum chamber is provided with a metal baffle, which forms an annular gap with the side wall of the vacuum chamber. The gas supply system also includes a vacuum pump for extracting the reaction gas from the vacuum chamber through the annular gap.

9. The microwave plasma chemical vapor deposition apparatus as described in claim 8, characterized in that, The vacuum pump includes a wet vacuum pump connected to the vacuum chamber via a first flow control valve and a dry vacuum pump connected to the vacuum chamber via a second flow control valve. The dry vacuum pump extracts gas from the vacuum chamber and circulates it back into the vacuum chamber through a second flow equalization ring.

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