MPCVD microwave single crystal growth pressure control device, growth equipment and use method

Abstract

The invention provides an MPCVD microwave single crystal growth pressure control device and growth equipment provided with the same, the MPCVD microwave single crystal growth pressure control device comprises a furnace body and a vacuum pump, and is characterized in that a filter is arranged between the furnace body and the vacuum pump, and two side pipelines for communicating the furnace body with the vacuum pump are arranged at two ends of the filter; the air inlets and the air outlets of the two side pipelines are mutually crossed, and at least one control valve is arranged on each side pipeline. The pressure control device for MPCVD microwave single crystal growth is simple in structure and easy to disassemble and assemble, the stability of airflow and the stability of pressure in the whole process of MPCVD microwave single crystal growth can be guaranteed, dust can be effectively filtered, the effectiveness and safety of pipeline smoothness can be guaranteed, and therefore the quality of diamond MPCVD microwave single crystal growth can be guaranteed. The invention further provides a using method of the pressure control device for MPCVD microwave single crystal growth.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of CVD diamond production, in particular to a MPCVD micro single crystal growth pressure control device, a growth device provided with the pressure control device, and a method for using the pressure control device. BACKGROUND

[0002] In the whole CVD diamond growth process, pressure stability is particularly important. Slight changes in pressure will cause changes in the state of the plasma in the reaction furnace, thereby changing the temperature of the CVD diamond, which will affect the product quality. Therefore, during the growth process, pressure stability is one of the key conditions to ensure diamond quality and long-term stable growth.

[0003] During the growth process, the pressure must be kept stable. The pressure in the furnace body is stabilized by the pressure feedback value of the thin film silicon surface on the pipeline, and the opening of the PID regulating electromagnetic proportional valve. However, during the actual growth process, some dust will be generated in the furnace body, deposited on the inner wall of the furnace body, and some dust will be discharged along the direction of the exhaust. After a long time of growth, a large amount of dust will be attached to the channel of the electromagnetic proportional valve, causing the diameter of the channel to gradually decrease. After the proportional regulating valve is opened to 100%, the existing air pressure cannot be adjusted, which will cause the pressure to be out of control. Forced shutdown will have a great impact on production. If it is not discovered in time, the pressure will completely lose control, the CVD diamond product will be directly scrapped, and significant economic losses will be caused. SUMMARY

[0004] The present application provides a MPCVD micro single crystal growth pressure control device, a growth device provided with the pressure control device, and a method for using the pressure control device, which solves the technical problems of poor pressure stability and easy blockage of the pipeline caused by unreasonable gas path control design in the prior art.

[0005] To solve at least one of the above technical problems, the technical solution adopted by the present application is:

[0006] The MPCVD micro single crystal growth pressure control device comprises a furnace body and a vacuum pump, a filter is arranged between the furnace body and the vacuum pump, two side pipes for connecting the furnace body and the vacuum pump are arranged at both ends of the filter, the gas inlet and outlet of the two side pipes are arranged in a cross manner, and at least one control valve is arranged on each side pipe.

[0007] Further, the control valves for controlling the flow of gas through the filter are arranged at both ends of the filter;

[0008] Preferably, the control valve for controlling the flow through the filter outlet is arranged on the pipeline between the filter and the electromagnetic proportional valve, and is located outside the intersection position of the two side pipes near the end of the vacuum pump.

[0009] Further, the control valve for controlling the flow through the filter outlet is arranged outside the two side pipes near the end of the vacuum pump.

[0010] Preferably, the electromagnetic proportional valve is arranged at the outlet of the filter.

[0011] Further, the electromagnetic proportional valve is arranged between the intersection positions of the two side pipes near the end of the vacuum pump.

[0012] Further, two control valves are arranged in one of the side pipes, respectively at the two ends of the side pipe.

[0013] Further, the other side pipe with one control valve is arranged near the end of the furnace body.

[0014] Further, the control valve is a pneumatic valve, an electromagnetic valve or a manual valve.

[0015] A growth device is provided with the MPCVD micro single crystal growth pressure control device as described above.

[0016] A method for using the MPCVD micro single crystal growth pressure control device as described above, comprising the following steps: when the gas flow in the furnace body cannot flow to the vacuum pump through the filter during MPCVD micro single crystal growth, one of the side pipes is controlled to be opened to guide the gas flow into the vacuum pump.

[0017] Further, when the filter is used again,

[0018] First, the side pipe I for replacing the filter and the electromagnetic proportional valve are kept in working state, and the side pipe II is opened to use the vacuum pump to pump out the gas flow in the filter until the inside of the filter reaches a vacuum state.

[0019] Then, the side pipe I and the side pipe II are closed, and the control valve I and the control valve II at the two ends of the filter are opened synchronously to make the gas flow in the furnace body flow through the filter and then into the vacuum pump.

[0020] The MPCVD microwave single crystal growth pressure control device designed in this application has a simple structure and is easy to assemble and disassemble. It not only ensures the stability of airflow and pressure throughout the entire MPCVD microwave single crystal growth process, but also effectively filters dust, ensuring the effectiveness and safety of pipeline unobstructed flow, thereby guaranteeing the quality of diamond MPCVD microwave single crystal growth. This application also proposes a growth apparatus equipped with this pressure control device, and a method for using this pressure control device in MPCVD microwave single crystal growth. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of an MPCVD microwave single crystal growth pressure control device according to an embodiment of this application;

[0022] Figure 2 This is a flowchart of a method for using a pressure control device according to an embodiment of this application.

[0023] In the picture:

[0024] 10, furnace body 20, vacuum pump 30, filter 31, control valve one 32, control valve two 40, electromagnetic proportional valve 50, side pipe one 51, control valve three 52, control valve four 60, side pipe two 61, control valve five Detailed Implementation

[0025] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0026] This embodiment proposes a pressure control device for MPCVD microwave single crystal growth, such as... Figure 1 As shown, the system includes a furnace body 10 and a vacuum pump 20. A filter 30 is installed between the furnace body 10 and the vacuum pump 20. Two side pipes, namely side pipe 50 and side pipe 60, are constructed at both ends of the filter 30 to connect the furnace body 10 and the vacuum pump 20. The air inlets and outlets of side pipe 50 and side pipe 60 are arranged in a cross configuration, and each side pipe 50 and side pipe 60 is equipped with at least one control valve. The two side pipes can continue to connect the furnace body 10 and the vacuum pump 20 when the filter 30 is not working properly, while ensuring that the airflow can flow smoothly from the furnace body 10 to the vacuum pump 20. Furthermore, when the filter 30 is reused, the air in the filter 30 can be pre-emptively drawn into the vacuum pump 20 without affecting the airflow during MPCVD microwave single crystal growth.

[0027] Specifically, control valve one 31 and control valve two 32 are arranged at both ends of filter 30 for controlling the flow of gas through filter 30, control valve one 31 is arranged at the side of filter 30 close to furnace body 10, and control valve two 32 is arranged at the side of filter 30 close to vacuum pump 20. An electromagnetic proportional valve 40 is further arranged on the pipeline at the end of filter 30 close to vacuum pump 20 for adjusting the flow of gas, and the electromagnetic proportional valve 40 adjusts the opening of its valve port to adjust the flow rate of the gas flow, so as to better control the stability of the gas flow and the stability of the pressure.

[0028] In order to ensure the stability of the flow of gas through filter 30 or bypass pipeline one 50 to vacuum pump 20, control valve two 32 must be arranged at the side of electromagnetic proportional valve 40 close to filter 30, that is, control valve two 32 is arranged on the pipeline between filter 30 and electromagnetic proportional valve 40.

[0029] Since filter 30 is mainly used to filter impurities in the gas flow, dust is easily accumulated on filter 30 over time, causing filter 30 to be blocked and unable to work normally, thereby affecting the normal flow of the gas flow, and filter 30 needs to be disassembled, cleaned and then used again.

[0030] In order to ensure the smoothness of the gas flow between furnace body 10 and vacuum pump 20 when filter 30 is disassembled and installed, two bypass pipelines are provided, namely bypass pipeline one 50 and bypass pipeline two 60. Bypass pipeline one 50 is used to connect furnace body 10 and vacuum pump 20, that is, the standby air pipeline of filter 30; bypass pipeline two 60 is used to connect the main gas flow pipeline of the gas inlet and gas outlet of filter 30, and its function is to, when filter 30 needs to be re-used in the system, without stopping, the air in the cavity of filter 30 is pumped to vacuum pump 20 to restore it to the required vacuum state, so as to ensure the effectiveness and safety of its internal use again.

[0031] Two control valves are arranged on bypass pipeline one 50, namely control valve three 51 and control valve four 52, which are respectively arranged at both ends of bypass pipeline one 50, wherein control valve three 51 is used to control the gas inlet of bypass pipeline one 50, and control valve four 52 is used to control the gas outlet of bypass pipeline one 50.

[0032] Only one control valve is arranged on bypass pipeline two 60, that is, control valve five 61, which is mainly used to control the flow of gas in filter 30 pumped away by vacuum pump 20.

[0033] The gas inlet of the side pipe one 50 is arranged near the side of the furnace body 10, and the gas inlet of the side pipe two 60 is arranged near one end of the filter 30. The gas outlet of the side pipe one 50 is arranged near the side of the filter 30, and the gas outlet of the side pipe two 60 is arranged near one end of the vacuum pump 20, i.e. between the electromagnetic proportional valve 40 and the vacuum pump 20. The electromagnetic proportional valve 40 is arranged between the gas outlet of the side pipe one 50 and the gas outlet of the side pipe two 60.

[0034] The two side pipes with different structures are arranged to obtain a pipe with different flow directions, i.e. one flow line from the furnace body 10, the side pipe one 50, the electromagnetic proportional valve 40 to the vacuum pump 20; and one flow line from the filter 30, the side pipe two 60 directly to the vacuum pump 20. The two different lines can protect different states of the filter 30 to ensure the stability and safety of the MPCVD micro single crystal growth gas line.

[0035] In the embodiment, the control valve one 31 is arranged between the intersection position of the side pipe one 50 and the side pipe two 60 near one end of the furnace body 10, i.e. between the control valve three 51 and the control valve five 61. The control valve two 32 is arranged outside the side pipe one 50 and the side pipe two 60 near one end of the vacuum pump 20 and away from the vacuum pump 20, i.e. arranged outside the side pipe one 50 and near one end of the filter 30.

[0036] Since the side pipe two 60 is only used to control the air vacuum state in the filter 30 itself, only one control valve five 61 is needed.

[0037] When the filter 30 works normally, the control valve one 31 and the control valve two 32 are opened, the side pipe one 50 and the side pipe two 60 are closed, i.e. the control valve three 51, the control valve four 52 and the control valve five 61 are closed; and the gas flow can flow from the furnace body 10 to the vacuum pump 20 through the control valve one 31, the filter 30, the control valve two 32 and the electromagnetic proportional valve 40 in sequence.

[0038] When the filter 30 cannot work normally, the pressure in the furnace body 10 is unstable, indicating that the filter 30 needs to be cleaned to ensure the normal growth. Therefore, the side pipeline 260 is closed and the control valve 261 is closed, and the control valve 231 and the control valve 232 are closed; the side pipeline 150 is opened, that is, the control valve 251 and the control valve 252 are opened; the electromagnetic proportional valve 40 continues to work, and the gas flow from the furnace body 10 is sequentially controlled by the control valve 251 for the gas inlet of the side pipeline 150, the control valve 252 for the gas outlet, and the electromagnetic proportional valve 40 to the vacuum pump 20. During this process, if the filter 30 needs to be cleaned, the filter 30 can be removed and cleaned. Of course, a new filter 30 can also be replaced or the filter 30 can be maintained during this process. At this time, the gas flow between the furnace body 10 and the vacuum pump 20 is not affected, the stability of the gas pressure in the furnace body 10 is ensured, and the quality of the MPCVD micro single crystal growth is ensured.

[0039] When the filter 30 is cleaned, or replaced with a new filter 30, or maintained, the filter 30 needs to be used again. Before being used again, the air in the filter 30 needs to be exhausted to make the inside of the filter 30 into a vacuum state.

[0040] When the filter 30 is used again, the side pipeline 150 is kept open, that is, the control valve 251 and the control valve 252 are opened; and the electromagnetic proportional valve 40 works normally; at the same time, the side pipeline 260 is opened, that is, the control valve 261 is opened; and the control valve 231 and the control valve 232 are kept closed. At this time, for the main gas path, the gas flow from the furnace body 10 is sequentially controlled by the side pipeline 150 and the electromagnetic proportional valve 40 to the vacuum pump 20 to maintain growth; for the vacuum path, the vacuum pump 20 is used to exhaust the gas flow in the filter 30 through the side pipeline 260 until the inside of the filter 30 reaches a vacuum state.

[0041] Subsequently, the normal working condition is switched back, the side pipeline 150 and the side pipeline 260 are closed, that is, the control valve 251, the control valve 252 and the control valve 261 are closed; the control valve 231 and the control valve 232 are opened synchronously; the gas path is restored, and the gas flow from the furnace body 10 is sequentially controlled by the control valve 231, the filter 30, the control valve 232 and the electromagnetic proportional valve 40 to the vacuum pump 20.

[0042] When the filter 30 is replaced during the process of the MPCVD micro single crystal growth, the filter 30 needs to be vacuumized without stopping the furnace. Therefore, the side pipeline 1 50 and the electromagnetic proportional valve 40 need to be continuously controlled to work, that is, the control valve 3 51 and the control valve 4 52 are opened, and the control valve 1 31 and the control valve 2 32 are closed. After the gas flow is extracted from the furnace 10, the gas flow sequentially passes through the side pipeline 1 50, the electromagnetic proportional valve 40, and then enters the vacuum pump 20. Then, the control valve 5 61 is opened, the side pipeline 2 60 is opened through the control valve 5 61, so that the filter 30 is communicated with the vacuum pump 20, and then the waste gas or air in the filter 30 is completely sucked by the vacuum pump 20, until the filter 30 is in a vacuum state.

[0043] After the vacuum state of the filter 30 is adjusted, the electromagnetic proportional valve 40 and the vacuum pump 20 continue to work, the control valve 3 51, the control valve 4 52, and the control valve 5 61 are closed to close the side pipeline 1 50 and the side pipeline 2 60. The control valve 1 31 and the control valve 2 32 are opened synchronously, so that the filter 30 is communicated with the furnace 10 and the vacuum pump 20 respectively. The gas flow sequentially passes through the control valve 1 31, the filter 30, the control valve 2 32, the electromagnetic proportional valve 40, and then enters the vacuum pump 20 again, so as to continue the filtering circulation.

[0044] In the embodiment, all the control valves are one of pneumatic valves, electromagnetic valves, or manual valves.

[0045] A growth device is provided with the MPCVD micro single crystal growth pressure control device as described above.

[0046] A use method of the MPCVD micro single crystal growth pressure control device as described above, the steps include:

[0047] When the gas flow in the furnace 10 cannot pass through the filter 30 to the vacuum pump 20 during the MPCVD micro single crystal growth, that is, when it is found that the gas pressure in the furnace 10 is abnormal, the filter 30 may be blocked and cannot work normally. The side pipeline 1 50 can be opened to guide the gas flow into the vacuum pump 20.

[0048] Specifically, the side pipeline 1 50 is opened, the side pipeline 2 60 is closed, and the control valve 1 31 and the control valve 2 32 are closed. The furnace 10, the vacuum pump 20, and the electromagnetic proportional valve 40 continue to work. After the gas flow is extracted from the furnace 10, the gas flow sequentially passes through the control valve 3 51 for controlling the gas inlet of the side pipeline 1 50, the control valve 4 52 for controlling the gas outlet, and then flows to the vacuum pump 20 through the electromagnetic proportional valve 40.

[0049] In this process, if the filter 30 needs to be cleaned, the filter 30 can be removed for cleaning, and after cleaning, the filter 30 can be used again. If the filter 30 cannot be cleaned, the filter 30 can be removed and replaced with a new filter 30. Of course, the filter 30 can also be maintained in an emergency without stopping the furnace, and the operation can also be performed in this process. The arrangement of the side pipe 1 50 not only does not affect the normal flow of the gas flow between the furnace 10 and the vacuum pump 20, but also ensures the stability of the gas pressure in the furnace 10 without stopping the furnace, so that the MPCVD micro single crystal can be normally grown, and the quality of the MPCVD micro single crystal growth can be ensured. This state can continue to grow the MPCVD micro single crystal until the growth is completed.

[0050] Further, when the filter 30 is used again during the growth of the MPCVD micro single crystal, the side pipe 2 60 needs to be opened first to control the air in the filter 30 to flow to the vacuum pump 20 through the side pipe 2 60 until the filter 30 is in a vacuum state. Then, the side pipe 1 50 and the side pipe 2 60 are closed to make the gas flow in the furnace 10 flow to the vacuum pump 20 through the filter 30.

[0051] Specifically, when the filter 30 is cleaned, or replaced with a new filter 30, or maintained, the filter 30 needs to be used again for work. When the filter needs to be used again, the side pipe 1 50 and the electromagnetic proportional valve 40 for replacing the filter are first kept in a working state, and the side pipe 2 60 is opened to use the vacuum pump 20 to extract the gas flow in the filter 30 until the inside of the filter 30 reaches a vacuum state; then, the side pipe 1 50 and the side pipe 2 60 are closed, and the control valve 1 31 and the control valve 2 32 at both ends of the filter 30 are opened synchronously, so that the gas flow in the furnace 10 resumes flowing through the filter 30 and then enters the vacuum pump 20.

[0052] Since this operation is performed after replacing the filter 30 during the growth of the MPCVD micro single crystal, the filter 30 needs to be vacuumized without stopping the furnace. Therefore, the side pipe 1 50 and the electromagnetic proportional valve 40 need to be continuously controlled to continue working, that is, the control valve 3 51 and the control valve 4 52 are opened, and the control valve 1 31 and the control valve 2 32 are continuously closed, so that the gas flow is extracted from the furnace 10 and then enters the vacuum pump 20 through the side pipe 1 50 and the electromagnetic proportional valve 40 in sequence; then, the control valve 5 61 is opened to open the side pipe 2 60 through the control valve 5 61, so that the filter 30 is communicated with the vacuum pump 20, and then the waste gas or air in the filter 30 can be completely sucked away by the vacuum pump 20 until the filter 30 is in a vacuum state.

[0053] After the vacuum state of the filter 30 is adjusted, the electromagnetic proportional valve 40 and the vacuum pump 20 continue to work, the control valve three 51, the control valve four 52 and the control valve five 61 are closed to close the side pipeline one 50 and the side pipeline two 60; and the control valve one 31 and the control valve two 32 are opened synchronously to make the filter 30 communicate with the furnace body 10 and the vacuum pump 20 respectively, so that the gas flow enters the vacuum pump 20 again from the furnace body 10 through the control valve one 31, the filter 30, the control valve two 32 and the electromagnetic proportional valve 40, and the filtering circulation is continued. In this state, the MPCVD micro single crystal can also be continuously grown until the growth is completed.

[0054] The MPCVD micro single crystal growth pressure control device designed in the application has simple structure and is easy to disassemble and assemble, can not only ensure the stability of the gas flow and the stability of the pressure in the whole process of the MPCVD micro single crystal growth, but also can effectively filter dust and ensure the effectiveness and safety of the smoothness of the pipeline, so as to ensure the quality of the diamond MPCVD micro single crystal growth. The application also provides a growth equipment provided with the pressure control device and a use method of the MPCVD micro single crystal growth using the pressure control device.

[0055] The above detailed description of the embodiments of the application is only the preferred embodiments of the application, and cannot be considered as limiting the scope of the application. Any equivalent changes and improvements made within the scope of the application should still belong to the patent coverage of the application.

Claims

1. A pressure control device for MPCVD micro-single crystal growth, comprising a furnace body and a vacuum pump, characterized in that, A filter is arranged between the furnace body and the vacuum pump, and two bypass pipes for connecting the furnace body and the vacuum pump are arranged at both ends of the filter, and the gas inlet and outlet of the two bypass pipes are arranged in a cross manner, and at least one control valve is arranged on each bypass pipe.

2. The MPCVD micro-single crystal growth pressure control device according to claim 1, characterized in that, The control valves for controlling the flow of gas through the filter are arranged at both ends of the filter; Preferably, the control valve for controlling the flow of gas through the outlet of the filter is arranged on the pipeline between the filter and the electromagnetic proportional valve, and is located outside the intersection position of the two bypass pipes near the end of the vacuum pump.

3. The apparatus for the growth of MPCVD micro-single crystals under pressure control according to claim 2, characterized in that The control valve for controlling the flow of gas through the outlet of the filter is arranged outside the two bypass pipes near the end of the vacuum pump, and away from the vacuum pump; Preferably, the electromagnetic proportional valve is arranged at the outlet of the filter.

4. The apparatus for the growth of MPCVD micro-single crystals under pressure control according to claim 3, characterized in that The electromagnetic proportional valve is arranged between the intersection positions of the two bypass pipes near the end of the vacuum pump.

5. The MPCVD micro-single crystal growth pressure control device according to any one of claims 1-4, characterized in that, One of the bypass pipes is provided with two control valves, one at each end of the bypass pipe.

6. The MPCVD micro-single crystal growth pressure control apparatus according to claim 5, wherein, The other bypass pipe is provided with one control valve, which is arranged near the end of the furnace body.

7. The MPCVD micro-single crystal growth pressure control device according to any one of claims 1-4, 6, characterized in that, The control valve can be a pneumatic valve, an electromagnetic valve or a manual valve.

8. A growing apparatus characterised in that, The MPCVD micro single crystal growth pressure control device as claimed in any one of claims 1-7 is arranged.

9. A method of using the MPCVD micro-single crystal growth pressure control apparatus according to any one of claims 1-7, characterized by the steps of It comprises: When the gas flow in the furnace body cannot flow through the filter to the vacuum pump during MPCVD micro single crystal growth, one of the bypass pipes can be opened to guide the gas flow into the vacuum pump.

10. The method of use of claim 9, wherein, Further comprising, when the filter is reused, First, keep the bypass pipe I and the electromagnetic proportional valve for replacing the filter in working condition, and open the bypass pipe II to use the vacuum pump to pump out the gas flow in the filter until the inside of the filter reaches a vacuum state; Then, close the bypass pipe I and the bypass pipe II, and simultaneously open the control valve I and the control valve II at both ends of the filter, so that the gas flow in the furnace body can flow through the filter and then enter the vacuum pump.

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