Gas supply pipeline and plasma enhanced chemical vapor deposition equipment

Abstract

The utility model relates to a gas supply pipeline and plasma enhanced chemical vapor deposition equipment. The gas supply pipeline comprises a cavity gas supply pipeline, a nitrogen cleaning pipeline, at least one first gas supply pipeline, at least one second gas supply pipeline and at least two nitrogen supply pipelines, the first gas supply pipeline and the second gas supply pipeline are respectively communicated with the cavity gas supply pipeline, and the at least two nitrogen supply pipelines are communicated with the cavity gas supply pipeline; at least one nitrogen supply pipeline is communicated with the nitrogen cleaning pipeline, the nitrogen cleaning pipeline is communicated with the first gas supply pipeline, the gas supply pipeline is additionally provided with a plurality of nitrogen supply pipelines on the basis of stably supplying gas by utilizing each process gas pipeline, and when the vacuum of the reaction cavity needs to be broken after the coating is finished, the nitrogen cleaning pipeline is communicated with the first gas supply pipeline. The reaction cavity of the PECVD equipment can be rapidly filled with nitrogen through the multiple nitrogen supply pipelines, the overall process time is shortened, and the productivity is improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic cell manufacturing equipment, and in particular to a gas supply pipeline and plasma enhanced chemical vapor deposition equipment. Background Art

[0002] PECVD (Plasma Enhanced Chemical Vapor Deposition) technology is a technology that uses active substances such as electrons and ions to catalyze chemical reactions to form thin films under low pressure. During the PECVD reaction process, the reaction chamber of the PECVD equipment needs to maintain a certain vacuum. When the process is completed and the next round of process is carried out, nitrogen needs to be introduced to break the vacuum so that the air pressure inside and outside the reaction chamber is balanced, which is convenient for taking out the products after the process. At present, when the vacuum breaking process is carried out in traditional PECVD equipment, it takes a long time, which reduces the overall process efficiency. In addition, the reaction gases used in existing PECVD equipment include harmful gases, inert gases, flammable gases, etc., especially for harmful gases and flammable gases. After the reaction of the PECVD equipment is completed, some gases will still remain inside the PECVD equipment, so that after the process is completed, the PECVD equipment needs to be opened for ventilation for a period of time before the reaction products can be taken out, which seriously slows down the process efficiency. Utility Model Content

[0003] In order to overcome the above-mentioned deficiencies of the prior art, the present application provides a gas supply pipeline and a plasma enhanced chemical vapor deposition device, which specifically adopts the following technical solutions:

[0004] A gas supply pipeline, comprising a cavity gas supply pipeline, a nitrogen cleaning pipeline, at least one first gas supply pipeline, at least one second gas supply pipeline and at least two nitrogen supply pipelines;

[0005] The first gas supply pipeline and the second gas supply pipeline are respectively connected to the cavity gas supply pipeline, at least two of the nitrogen supply pipelines are connected to the cavity gas supply pipeline; at least one of the nitrogen supply pipelines is connected to the nitrogen cleaning pipeline, and the nitrogen cleaning pipeline is connected to the first gas supply pipeline.

[0006] The above-mentioned gas supply pipeline utilizes the first gas supply pipeline and the second gas supply pipeline to realize the branch transmission of harmful gas and harmless gas, ensuring the stable gas supply of the gas supply pipeline; at the same time, the multi-channel nitrogen supply pipe is used to break the vacuum of the reaction chamber after the coating is completed, so as to realize the rapid nitrogen filling action of the PECVD equipment, reduce the overall process time and improve the production efficiency.

[0007] Optionally: the first gas supply pipeline includes a first manual diaphragm valve, a double pneumatic diaphragm valve, a first non-return valve, a first flow meter and a first single pneumatic diaphragm valve, the double pneumatic diaphragm valve is provided with two air inlets, one of which is connected to the air outlet of the first manual diaphragm valve through the first non-return valve, and the other air inlet is connected to the nitrogen cleaning pipeline through the first non-return valve; the air outlet of the double pneumatic diaphragm valve is connected to the air inlet of the first flow meter, and the air outlet of the first flow meter is connected to the cavity gas supply pipeline through the first single pneumatic diaphragm valve. The above-mentioned first gas supply pipeline is mainly used for the input of harmful gases or flammable gases, and it realizes the switching input of reactive gas and nitrogen through the double pneumatic diaphragm valve. The double pneumatic diaphragm valve can be used to input reactive gas into the PECVD equipment and clean and purge the pipeline. The external gas source is input / disconnected through the first manual diaphragm valve. The first one-way valve can ensure that the gas does not flow back. The input gas is input into the first single pneumatic diaphragm valve through the first flow meter. The first single pneumatic diaphragm valve can be used to connect and disconnect the corresponding reaction gas and the reaction chamber.

[0008] Optionally: the second gas supply pipeline includes a second manual diaphragm valve, a second one-way valve, a second flowmeter and a second single pneumatic diaphragm valve, the gas outlet of the second manual diaphragm valve is connected to the gas inlet of the second flowmeter through the second one-way valve, and the gas outlet of the second flowmeter is connected to the cavity gas supply pipeline through the second single pneumatic diaphragm valve. The above-mentioned second gas supply pipeline is mainly used for the input of harmless gas or inert gas, the external gas source is input / disconnected through the second manual diaphragm valve, the second one-way valve ensures that the gas does not flow back, the input gas is input into the second single pneumatic diaphragm valve through the second flowmeter, and the second single pneumatic diaphragm valve can be used to realize the connection and disconnection of the corresponding reaction gas and the reaction chamber.

[0009] Optionally: the nitrogen supply pipeline includes a third manual diaphragm valve, a third one-way valve and a third single pneumatic diaphragm valve, the gas outlet of the third manual diaphragm valve is connected to the gas inlet of the third single pneumatic diaphragm valve through the third one-way valve, and the gas outlet of the third single pneumatic diaphragm valve is connected to the cavity gas supply pipeline. The above-mentioned nitrogen supply pipeline is mainly used for nitrogen input, and external nitrogen is input / disconnected through the third manual diaphragm valve. The third one-way valve can ensure that nitrogen does not flow back, and the third single pneumatic diaphragm valve can be used to realize the connection and disconnection of nitrogen and the reaction chamber.

[0010] Optionally: the cavity gas supply pipeline includes a first cavity gas supply pipeline and a second cavity gas supply pipeline, at least one of the first gas supply pipelines is connected to the second cavity gas supply pipeline, and the second gas supply pipeline is connected to the first cavity gas supply pipeline in parallel with the remaining first gas supply pipelines. During the process implementation of the PECVD equipment, a variety of reaction gases need to be introduced into the reaction chamber. Some reaction gases are more active. In order to avoid the reaction of the active reaction gas in the pipeline, this gas supply pipeline divides the cavity gas supply pipeline into two routes, one of which is used for the mixed input of inert gas, and the other is used for the single input of active gas to avoid reaction gas contamination.

[0011] Optionally: at least one of the nitrogen supply pipelines is provided with a first interface and a second interface, the first interface is located on the pipeline between the third manual diaphragm valve and the third one-way valve, and the second interface is located on the pipeline between the third one-way valve and the third single pneumatic diaphragm valve; the first interface is connected to the nitrogen cleaning pipeline; the second interface is connected in series with a fourth flowmeter and a fourth single pneumatic diaphragm valve in sequence, and the fourth single pneumatic diaphragm valve is connected to the cavity gas supply pipeline. At least two nitrogen supply pipelines are provided in this gas supply pipeline, one as the main nitrogen supply pipeline, and the other takes into account both nitrogen supply and clean purge supply. This gas supply pipeline can realize the switching between the two modes of nitrogen supply and clean purge supply in the reaction chamber by controlling the opening and closing of the manual diaphragm valves corresponding to the first interface and the second interface.

[0012] Optional: Also includes 90° welding elbow and T-shaped welding joint, the 90° welding elbow is used for connecting at the turning position in the pipeline, and the T-shaped welding joint is used for connecting at the intersection position in the pipeline. In this gas supply pipeline, 90° welding elbow and T-shaped welding joint are used for connecting at the turning and intersection positions of the pipeline, respectively, which can avoid the inner wall being damaged due to the bending of the pipeline itself, thereby increasing the service life of the pipeline.

[0013] Optionally: the first gas supply pipeline is provided with five channels, one of which is connected to the second cavity gas supply pipeline, and the remaining four first gas supply pipelines are connected in parallel to the first cavity gas supply pipeline; the second gas supply pipeline is provided with three channels, and the three second gas supply pipelines are connected in parallel to the first cavity gas supply pipeline. In order to ensure the stable implementation of the PECVD equipment process, this gas supply pipeline is respectively provided with multiple first gas supply pipelines and multiple second gas supply pipelines, which can realize the simultaneous supply of multiple reaction gases, avoid the disassembly and switching of reaction gases, and thus improve the reaction efficiency of the equipment.

[0014] Optional: The pipeline size of the cavity gas supply pipeline and the nitrogen purge pipeline is 3 / 8" and above. In the present gas supply pipeline, the cavity gas supply pipeline and the nitrogen purge pipeline usually input multiple gases at the same time during the process. The use of pipelines with a size of 3 / 8" and above can pass a larger gas flow rate to meet the gas consumption requirements of large-volume equipment.

[0015] In addition, the present application also discloses a plasma enhanced chemical vapor deposition device, which uses the gas supply pipeline as mentioned above to supply process gas.

[0016] Beneficial Effects

[0017] The technical solution of this application has the following beneficial effects:

[0018] (1) The gas supply pipeline of the present application realizes stable gas supply through design optimization of each process gas pipeline in the gas supply pipeline, and adds multiple nitrogen supply pipelines. When the reaction chamber needs to break the vacuum after the coating is completed, the multiple nitrogen supply pipelines can quickly fill the reaction chamber of the PECVD equipment with nitrogen, thereby reducing the overall process time and improving production capacity.

[0019] (2) The gas supply pipeline of the present application is equipped with a nitrogen purge pipeline for harmful and flammable process gases. The nitrogen purge pipeline is connected in parallel with the process gas supply pipeline through a double pneumatic diaphragm valve, so that the pipeline can be purged after each round of process. This can avoid the leakage of toxic and flammable gases remaining in the pipeline when replacing process products, and at the same time prevent gas pollution and reduce product quality. For harmless inert gases, the double pneumatic diaphragm valve is removed, which reduces the installation cost of the supply pipeline and reduces the space occupied by the pipeline.

[0020] (3) The gas supply pipeline of the present application adopts 90° welded elbows and T-shaped welded joints for the turning or intersection of the pipeline, which can improve the tensile damage of the inner wall of the pipeline after the traditional pipeline is bent. The use of the above-mentioned welded elbows or welded joints can avoid the degradation of the surface properties of the pipeline material, thereby avoiding corrosion and leakage of the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of the gas supply pipeline in this application.

[0022] Figure 2 This is a schematic diagram of the circuit principle of the gas supply pipeline in this application.

[0023] 1. Gas circuit bottom plate; 2. First cavity gas supply pipeline; 3. Second cavity gas supply pipeline; 4. Nitrogen cleaning pipeline; 5-1. First one-way valve; 5-2. Second one-way valve; 5-3. Third one-way valve; 6. Double pneumatic diaphragm valve; 7-1. First flow meter; 7-2. Second flow meter; 7-3. Third flow meter; 7-3. Fourth flow meter; 8-1. First single pneumatic diaphragm valve; 8-2. Second single pneumatic diaphragm valve; 8-3. Third single pneumatic diaphragm valve; 8-4. Fourth single pneumatic diaphragm valve; 9-1. First manual diaphragm valve; 9-2. Second manual diaphragm valve; 9-3. Third manual diaphragm valve; 10. First interface; 11. Second interface; 12. 90° welding elbow; 13. T-type welding joint; 14. Nitrogen supply pipeline; 15. First gas supply pipeline; 16. First gas supply pipeline. DETAILED DESCRIPTION

[0024] The present application is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and cannot be used to limit the scope of protection of the present application. It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanation of the present application.

[0025] It should be understood that the terms "first", "second", "third", and "fourth" herein are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the feature. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0026] In this document, unless otherwise clearly specified and limited, the term "connection" and other terms should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] At present, when performing the vacuum breaking process in the traditional PECVD equipment, a nitrogen supply pipeline is usually used for nitrogen supply. Due to the flow limit of the supply pipeline, it takes a long time to perform the vacuum breaking process with a single nitrogen supply pipeline, which prolongs the overall process time and reduces the overall process efficiency. In order to improve the vacuum breaking efficiency, it is necessary to increase the flow rate of nitrogen to ensure that the reaction chamber of the PECVD equipment is filled in a short time. In addition, the reaction gases used in the existing PECVD equipment include harmful gases, inert gases, flammable gases, etc., especially for harmful gases and flammable gases. After the reaction of the PECVD equipment is completed, some harmful and flammable gases will still remain inside the PECVD equipment. After analysis, it is found that some of the remaining gases come from the residues in the supply pipelines of each process gas. In order to quickly blow away the remaining gases, it is necessary to use harmless gases to blow out the residual gases in the supply pipelines of each process gas after the process is completed.

[0028] To solve the above problems, this embodiment discloses a gas supply pipeline, such as Figure 1 and Figure 2 As shown, it is used to supply process gas to plasma enhanced chemical vapor deposition equipment. The gas supply pipeline is uniformly fixed on the gas circuit base plate 1. The gas supply pipeline includes a cavity gas supply pipeline, a nitrogen cleaning pipeline 4, at least one first gas supply pipeline 15, at least one second gas supply pipeline 16 and at least two nitrogen supply pipelines 14.

[0029] Specifically, in this embodiment, the first gas supply pipeline 15 and the second gas supply pipeline 16 are respectively connected to the cavity gas supply pipeline, and the cavity gas supply pipeline is used to transport gas into the reaction chamber of the PECVD equipment. The first gas supply pipeline 15 of this embodiment is mainly used to transport toxic, harmful, flammable and other process gases, and the second gas supply pipeline 16 is mainly used to transport non-toxic, harmless and other process gases. The use of the first gas supply pipeline and the second gas supply pipeline in the above-mentioned gas supply pipeline can realize the branch transportation of harmful gases and harmless gases, ensuring the stable gas supply of the gas supply pipeline;

[0030] At least two of the nitrogen supply pipelines 14 are connected to the cavity gas supply pipeline; at least one of the nitrogen supply pipelines 14 is connected to the nitrogen cleaning pipeline 4, and the nitrogen cleaning pipelines 4 are respectively connected to the first gas supply pipeline 15. The nitrogen cleaning pipeline 4 can deliver nitrogen to the first gas supply pipeline 15 to purge the internal gas of the first gas supply pipeline 15. Another nitrogen supply pipeline 14 is connected to the cavity gas supply pipeline for nitrogen replenishment. After the coating is completed, the reaction chamber is broken by multiple nitrogen supply pipelines 14 to realize the rapid nitrogen filling action of the PECVD equipment, reduce the overall process time, and improve the production efficiency.

[0031] Optionally, the cavity gas supply pipeline described in this embodiment includes a first cavity gas supply pipeline 2 and a second cavity gas supply pipeline 3, at least one of the first gas supply pipelines 15 is connected to the second cavity gas supply pipeline 3, and the second gas supply pipeline 16 is connected to the first cavity gas supply pipeline 2 in parallel with the remaining first gas supply pipelines 15. During the process implementation, the PECVD equipment needs to introduce a variety of reaction gases into the reaction chamber. Some reaction gases are relatively active. In order to avoid the reaction of active reaction gases in the pipeline, this gas supply pipeline divides the cavity gas supply pipeline into two routes, one of which is used for the mixed input of inert gases, and the other is used for the separate input of active gases. In this embodiment, the use of two cavity gas supply pipelines avoids the reaction of process gases when they are mixed and affects the subsequent process. By separately delivering the active gas and the inert gas, the reaction is carried out in the reaction chamber as much as possible to avoid reaction gas contamination.

[0032] Specifically, in this embodiment, the first gas supply pipeline 15 is provided with five channels, one of which is connected to the second cavity gas supply pipeline 3, and the remaining four first gas supply pipelines 15 are connected in parallel to the first cavity gas supply pipeline 2; the second gas supply pipeline 16 is provided with three channels, and the three second gas supply pipelines 16 are connected in parallel to the first cavity gas supply pipeline 2. In order to ensure the stable implementation of the PECVD equipment process, the gas supply pipeline is respectively provided with multiple first gas supply pipelines 15 and multiple second gas supply pipelines 16, which can realize the simultaneous supply of multiple reaction gases, avoid the disassembly and switching of reaction gases, and thus improve the reaction efficiency of the equipment.

[0033] More specifically, in this embodiment, the first gas supply pipeline 15 includes a first manual diaphragm valve 9-1, a dual pneumatic diaphragm valve 6-1, a first one-way valve 5-1, a first flowmeter 7-1 and a first single pneumatic diaphragm valve 8-1. One air inlet of the dual pneumatic diaphragm valve 6 is connected to the air outlet of the first manual diaphragm valve 9-1 through the first one-way valve 5-1, and the other air inlet is connected to the nitrogen cleaning pipeline 4 through the first one-way valve 5-1; the air outlet of the dual pneumatic diaphragm valve 6 is connected to the air inlet of the first flowmeter 7-1, and the air outlet of the first flowmeter 7-1 is connected to the cavity air supply pipeline through the first single pneumatic diaphragm valve 8-1. In this embodiment, the process gas is introduced through the first manual diaphragm valve 9-1, and then passes into one of the air inlets of the double pneumatic diaphragm valve 6 through the first one-way valve 5-1. Then, the process gas passes into the first flow meter 7-1 through the air outlet of the double pneumatic diaphragm valve 6 for metering, and finally passes into the cavity air supply pipeline through the first single pneumatic diaphragm valve 8-1.

[0034] The first gas supply pipeline 15 is mainly used for the input of harmful gas or flammable gas. It realizes the switching input of reaction gas and nitrogen through the double pneumatic diaphragm valve. The double pneumatic diaphragm valve can be used to input the reaction gas to the PECVD equipment and clean and purge the pipeline. The external gas source is input / disconnected through the first manual diaphragm valve 9-1. The first one-way valve 5-1 can ensure that the gas does not flow back. The input gas is input into the first single pneumatic diaphragm valve 8-1 through the first flowmeter 7-1. The first single pneumatic diaphragm valve 8-1 can realize the connection and disconnection of the corresponding reaction gas and the reaction chamber.

[0035] More specifically, in this embodiment, the second gas supply pipeline 16 includes a second manual diaphragm valve 9-2, a second one-way valve 5-2, a second flowmeter 7-2 and a second single pneumatic diaphragm valve 8-2, the gas outlet of the second manual diaphragm valve 9-2 is connected to the gas inlet of the second flowmeter 7-2 through the second one-way valve 5-2, and the gas outlet of the second flowmeter 7-2 is connected to the cavity gas supply pipeline through the second single pneumatic diaphragm valve 8-2. The process gas is introduced through the second manual diaphragm valve 9-2, and then the process gas flows into the second flowmeter 7-2 through the second one-way valve 5-2 for metering, and finally enters the cavity gas supply pipeline through the second single pneumatic diaphragm valve 8-2.

[0036] The above-mentioned second gas supply pipeline 16 is mainly used for the input of harmless gas or inert gas. The external gas source realizes the input / disconnection of the gas source through the second manual diaphragm valve 9-2. The second one-way valve 5-2 ensures that the gas does not flow back. The input gas is input into the second single pneumatic diaphragm valve 8-2 through the second flow meter 7-2. The second single pneumatic diaphragm valve 8-2 can realize the connection and disconnection of the corresponding reaction gas and the reaction chamber.

[0037] In more detail, the nitrogen supply pipeline 14 described in this embodiment includes a third manual diaphragm valve 9-3, a third one-way valve 5-3 and a third single pneumatic diaphragm valve 8-3. The air outlet of the third manual diaphragm valve 9-3 is connected to the air inlet of the third single pneumatic diaphragm valve 8-3 through the third one-way valve 5-3, and the air outlet of the third single pneumatic diaphragm valve 8-3 is connected to the cavity air supply pipeline.

[0038] The above-mentioned nitrogen supply pipeline is mainly used for nitrogen input. External nitrogen is input / disconnected through the third manual diaphragm valve 9-3. The third one-way valve 5-3 can ensure that nitrogen does not flow back. The third single pneumatic diaphragm valve 8-3 can realize the connection and disconnection of nitrogen and the reaction chamber.

[0039] Furthermore, in the present embodiment, a first interface 10 and a second interface 11 are provided in one of the nitrogen supply pipelines 14, the first interface 10 is located on the pipeline between the third manual diaphragm valve 9-3 and the third one-way valve 5-3, and the second interface 11 is located on the pipeline between the third one-way valve 5-3 and the third single pneumatic diaphragm valve 8-3; the first interface 10 is connected to the nitrogen cleaning pipeline 4; the second interface 11 is connected in series with the fourth flowmeter 7-4 and the fourth single pneumatic diaphragm valve 8-4 in sequence, and the fourth single pneumatic diaphragm valve 8-4 is connected to the cavity gas supply pipeline. At least two nitrogen supply pipelines are provided in the present gas supply pipeline, one as the main nitrogen supply pipeline, and the other for both nitrogen supply and clean purge supply. The present gas supply pipeline can realize the switching between the two modes of nitrogen supply and clean purge supply in the reaction chamber by controlling the opening and closing of the manual diaphragm valves corresponding to the first interface and the second interface. In this embodiment, when the third single pneumatic diaphragm valve 8-3 leading to the cavity gas supply line is closed, the nitrogen supply line 14 can directly introduce nitrogen into the nitrogen cleaning line 4 through the first interface 10, thereby achieving purging and cleaning of each gas supply line; and when the third single pneumatic diaphragm valve 8-3 leading to the cavity gas supply line is opened, the nitrogen supply line 14 can transport nitrogen to the cavity gas supply line through the second interface 11, thereby filling the reaction chamber with nitrogen. It should be noted that the gas supply pipeline of this embodiment also includes a 90° welded elbow 12 and a T-shaped welded joint 13, wherein the 90° welded elbow 12 is used for connecting at the turning position in the pipeline, and the T-shaped welded joint 13 is used for connecting at the intersection position in the pipeline. Once a traditional pipeline is bent, the inner wall of the pipeline will be stretched and the surface properties of the material will be destroyed, causing corrosion and gas leakage in the pipeline. Using a 90° welded elbow 12 and a T-shaped welded joint 13 to turn and intersect the pipeline can avoid pipeline bending and increase the life of the pipeline.

[0040] In addition, the pipeline size of the cavity gas supply pipeline and the nitrogen cleaning pipeline 4 described in this embodiment must be ensured to be 3 / 8" and above. In the present gas supply pipeline, the cavity gas supply pipeline and the nitrogen cleaning pipeline usually input multiple gases at the same time during the process. The use of pipelines with a size of 3 / 8" and above can pass a larger gas flow rate to meet the gas consumption requirements of large-capacity equipment.

[0041] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A gas supply pipeline, characterized in that: It comprises a cavity gas supply pipeline, a nitrogen cleaning pipeline (4), at least one first gas supply pipeline (15), at least one second gas supply pipeline (16) and at least two nitrogen supply pipelines (14); The first gas supply pipeline (15) and the second gas supply pipeline (16) are respectively connected to the cavity gas supply pipeline, and at least two of the nitrogen supply pipelines (14) are connected to the cavity gas supply pipeline; at least one of the nitrogen supply pipelines (14) is connected to the nitrogen cleaning pipeline (4), and the nitrogen cleaning pipeline (4) is connected to the first gas supply pipeline (15).

2. The gas supply pipeline according to claim 1, characterized in that: The first gas supply pipeline (15) comprises a first manual diaphragm valve (9-1), a double pneumatic diaphragm valve (6), a first non-return valve (5-1), a first flow meter (7-1) and a first single pneumatic diaphragm valve (8-1); the double pneumatic diaphragm valve (6) is provided with two air inlets, one of which is connected to the air outlet of the first manual diaphragm valve (9-1) through the first non-return valve (5-1), and the other air inlet is connected to the nitrogen cleaning pipeline (4) through the first non-return valve (5-1); the air outlet of the double pneumatic diaphragm valve (6) is connected to the air inlet of the first flow meter (7-1), and the air outlet of the first flow meter (7-1) is connected to the cavity air supply pipeline through the first single pneumatic diaphragm valve (8-1).

3. The gas supply pipeline according to claim 1, characterized in that: The second gas supply pipeline (16) comprises a second manual diaphragm valve (9-2), a second one-way valve (5-2), a second flow meter (7-2) and a second single pneumatic diaphragm valve (8-2); the gas outlet of the second manual diaphragm valve (9-2) is connected to the gas inlet of the second flow meter (7-2) via the second one-way valve (5-2); the gas outlet of the second flow meter (7-2) is connected to the cavity gas supply pipeline via the second single pneumatic diaphragm valve (8-2).

4. The gas supply pipeline according to claim 1, characterized in that: The nitrogen supply pipeline (14) comprises a third manual diaphragm valve (9-3), a third one-way valve (5-3) and a third single pneumatic diaphragm valve (8-3); the gas outlet of the third manual diaphragm valve (9-3) is connected to the gas inlet of the third single pneumatic diaphragm valve (8-3) via the third one-way valve (5-3); and the gas outlet of the third single pneumatic diaphragm valve (8-3) is connected to the cavity gas supply pipeline.

5. The gas supply pipeline according to claim 1, characterized in that: The cavity gas supply pipeline comprises a first cavity gas supply pipeline (2) and a second cavity gas supply pipeline (3), at least one of the first gas supply pipelines (15) is connected to the second cavity gas supply pipeline (3), and the second gas supply pipeline (16) is connected in parallel with the remaining first gas supply pipelines (15) to the first cavity gas supply pipeline (2).

6. The gas supply pipeline according to claim 4, characterized in that: At least one of the nitrogen supply pipelines (14) is provided with a first interface (10) and a second interface (11), the first interface (10) being located on the pipeline between the third manual diaphragm valve (9-3) and the third one-way valve (5-3), and the second interface (11) being located on the pipeline between the third one-way valve (5-3) and the third single pneumatic diaphragm valve (8-3); the first interface (10) is connected to the nitrogen cleaning pipeline (4); the second interface (11) is sequentially connected in series with a fourth flow meter (7-4) and a fourth single pneumatic diaphragm valve (8-4), and the fourth single pneumatic diaphragm valve (8-4) is connected to the cavity gas supply pipeline.

7. The gas supply pipeline according to claim 1, characterized in that: It also includes a 90° welding elbow and a T-shaped welding joint. The 90° welding elbow is used for connecting at a turning position in the gas supply pipeline, and the T-shaped welding joint is used for connecting at a junction position in the gas supply pipeline.

8. The gas supply pipeline according to claim 5, characterized in that: The first gas supply pipeline (15) is provided with five routes, one of the first gas supply pipelines (15) is connected to the second cavity gas supply pipeline (3), and the remaining four of the first gas supply pipelines (15) are connected in parallel to the first cavity gas supply pipeline (2); the second gas supply pipeline (16) is provided with three routes, and the three second gas supply pipelines (16) are connected in parallel to the first cavity gas supply pipeline (2).

9. The gas supply pipeline according to claim 1, characterized in that: The pipe sizes of the cavity gas supply pipe and the nitrogen cleaning pipe (4) are 3 / 8″ and above.

10. A plasma enhanced chemical vapor deposition device, characterized in that: The device uses the gas supply pipeline as described in any one of claims 1 to 9 to supply process gas.

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