MPCVD device for diamond growth

Abstract

The utility model relates to an MPCVD device for diamond growth, which comprises a shell, the shell is provided with an upper cover, a water cooling table is arranged in the shell, a molybdenum table is arranged at the upper end of the water cooling table, an annular microwave quartz cover is arranged between the water cooling table and the upper cover, and a reaction cavity is defined by the upper cover, the microwave quartz cover and the water cooling table. The upper cover is provided with a plurality of windows hermetically connected with the upper cover and an air inlet channel communicated with the reaction cavity, the water cooling table comprises a horizontal part and a vertical part extending out of the bottom of the shell, an air outlet channel communicated with the reaction cavity is arranged in the water cooling table, a liquid cooling channel is further arranged in the water cooling table, and the liquid cooling channel is provided with a water inlet channel and a water outlet channel. The reaction cavity is good in sealing effect, external air can be effectively isolated, and the vacuum working environment in the reaction cavity is maintained.

Description

Technical Field

[0001] The utility model relates to the technical field of microwave plasma chemical vapor deposition, in particular to an MPCVD device for diamond growth. Background Art

[0002] Microwave plasma chemical vapor deposition (MPCVD) single crystal diamond growth technology stands out among many single crystal diamond preparation methods due to its advantages such as pollution-free microwave energy and pure gas raw materials. It has become one of the most promising technologies for preparing large-size, high-quality single crystal diamonds.

[0003] At present, the existing MPCVD devices such as Figure 3 As shown, a reaction chamber is formed between the upper cover plate of the cavity and the bottom plate of the cavity, but the sealing performance of the connection between the upper cover plate and the bottom plate of the existing device is poor, and the external air enters the reaction chamber through the connection between the upper cover plate and the bottom plate, polluting the reaction gas, thereby seriously reducing the product quality. Utility Model Content

[0004] In view of the problems existing in the prior art, the utility model provides an MPCVD device for diamond growth.

[0005] The utility model adopts the following technical solution to solve the above technical problems: an MPCVD device for diamond growth, comprising a shell, which has an upper cover, a water cooling stage is arranged in the shell, a molybdenum stage is arranged at the upper end of the water cooling stage, a microwave quartz cover in a circular shape is arranged between the water cooling stage and the upper cover, the upper cover, the microwave quartz cover and the water cooling stage form a reaction chamber, the upper cover is provided with a plurality of windows sealed with the upper cover and an air inlet channel connected with the reaction chamber, the water cooling stage comprises a horizontal portion and a vertical portion extending from the bottom of the shell, an air outlet channel connected with the reaction chamber is arranged in the water cooling stage, a liquid cooling channel is also arranged in the water cooling stage, and the liquid cooling channel has a water inlet channel and a water outlet channel.

[0006] As a preferred solution, the shell includes a bottom plate, a support ring arranged on the bottom plate, and an upper cover located at the upper end of the support ring.

[0007] As a preferred solution, the support ring is made of metal material and is provided with a plurality of through holes.

[0008] As a preferred solution, a coaxial waveguide is coaxially sleeved outside the vertical portion at the lower end of the bottom plate, the coaxial waveguide is connected to the inside of the shell, and a mode converter is provided at the lower end of the coaxial waveguide, which is connected to the microwave system.

[0009] As a preferred solution, the microwave system includes a microwave generator, an isolator, three pins and a rectangular waveguide connected in sequence, and the outlet of the rectangular waveguide is connected to the inlet flange of the mode converter, and the microwave transmitted through the rectangular waveguide enters the mode converter.

[0010] As a preferred solution, a short-circuit piston is connected to the right end of the mode converter, and the short-circuit piston is adjustable to slide left and right.

[0011] As a preferred solution, a lower vacuum sealing ring is provided at the connection between the microwave quartz cover and the water cooling stage, and an upper vacuum sealing ring is provided at the connection between the microwave quartz cover and the upper cover.

[0012] As a preferred solution, the upper cover is convex, and is further provided with a first condensation water channel and a second condensation water channel.

[0013] As a preferred solution, the gas outlet channel is connected to a vacuum pumping device for vacuuming the reaction chamber.

[0014] The beneficial effects of the present application are as follows: 1. The present application forms a reaction chamber by an upper cover, a microwave quartz cover and a water cooling stage, and a lower vacuum sealing ring is provided at the connection between the microwave quartz cover and the water cooling stage, and an upper vacuum sealing ring is provided at the connection between the microwave quartz cover and the upper cover, which has a good sealing effect and can effectively isolate the outside air, maintain the vacuum working environment in the reaction chamber, and effectively reduce the vacuum leakage rate, thereby realizing effective isolation of the reaction chamber from the outside air, and providing a favorable guarantee for the preparation of high-quality diamonds.

[0015] 2. The present application can effectively reduce the temperature and improve the water cooling effect by combining the liquid cooling channel in the water cooling table with the first condensing water channel and the second condensing water channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the utility model;

[0017] Figure 2 for Figure 1 A cross-sectional view of

[0018] Figure 3 It is a structural schematic diagram of the prior art.

[0019] Markings in the figure: 1. shell, 11. bottom plate, 12. support ring, 121. through hole, 13. upper cover, 2. mode converter, 3. water cooling table, 31. water inlet channel, 32. water outlet channel, 33. air outlet channel, 34. horizontal part, 35. vertical part, 4. co-coaxial waveguide, 5. molybdenum table, 6. microwave quartz cover, 7. air inlet channel, 8. first condensed water channel, 9. second condensed water channel. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail in conjunction with the accompanying drawings and embodiments. It should be understood that in the description of the utility model, unless otherwise specified, the meaning of "multiple" is two or more; the orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0021] See also Figure 1-2 The embodiment of the utility model provides an MPCVD device for diamond growth, including a shell 1, which has an upper cover 13, a water cooling table 3 is arranged in the shell 1, a molybdenum table 5 is arranged on the upper end of the water cooling table 3, a microwave quartz cover 6 in a circular shape is arranged between the water cooling table 3 and the upper cover 13, the upper cover 13, the microwave quartz cover 6 and the water cooling table 3 form a reaction chamber, the upper cover 13 is provided with a plurality of windows 131 sealed with the upper cover 13 and an air inlet channel 7 communicating with the reaction chamber, the water cooling table 3 includes a horizontal portion 34 and a vertical portion 35 extending from the bottom of the shell 1, an air outlet channel 33 communicating with the reaction chamber is arranged in the water cooling table 3, and a liquid cooling channel is also arranged in the water cooling table 3, and the liquid cooling channel has a water inlet channel 31 and a water outlet channel 32.

[0022] Among them, Figure 1 and Figure 2 As shown, the housing 1 includes a bottom plate 11 , a support ring 12 disposed on the bottom plate 11 , and an upper cover 13 located at the upper end of the support ring 12 . The support ring 12 is made of metal material and is provided with a plurality of through holes 121 .

[0023] Specifically, a coaxial waveguide 4 is coaxially sleeved on the outside of the vertical portion 35 at the lower end of the bottom plate 11, the coaxial waveguide 4 is connected to the inside of the shell 1, a mode converter 2 is provided at the lower end of the coaxial waveguide 4, the mode converter 2 is connected to a microwave system, the microwave system includes a microwave generator, a circulator, a three-pin and a rectangular waveguide connected in sequence, and the outlet of the rectangular waveguide is connected to the inlet flange of the mode converter 2, the microwave transmitted through the rectangular waveguide enters the mode converter 2, the right end of the mode converter 2 is connected to a short-circuit piston, and the short-circuit piston can slide left and right. In addition, the microwave system can adopt a microwave system commonly used by technicians in this field, the purpose is to generate microwaves. In addition, it should be noted that the parts not described in detail in this application are all prior art.

[0024] The microwave generator generates and emits microwaves, and the microwaves enter the three pins 3 through the circulator. After the adjustment of the three pins, the impedance matching of the entire microwave system can be achieved, which can reduce the microwave reflection power. The outlet of the three pins is bolted to the inlet flange of the rectangular waveguide. After the transmission of the rectangular waveguide, the microwaves enter the mode converter 2. The outlet of the rectangular waveguide is bolted to the inlet flange of the mode converter, and enter the coaxial waveguide 4 through the mode converter 2, so that the microwaves propagate upward along the coaxial waveguide 4, and then enter the shell 1, providing necessary reaction conditions for diamond growth. The right end of the mode converter 2 is connected to the short-circuit piston, so that as much microwave energy as possible enters the shell 1.

[0025] In addition, a lower vacuum sealing ring is provided at the connection between the microwave quartz cover 6 and the water cooling stage 3, and an upper vacuum sealing ring is provided at the connection between the microwave quartz cover 6 and the upper cover 13. The upper cover 13 is convex, and a first condensation water channel 8 and a second condensation water channel 9 are also provided on the upper cover 13. The gas outlet channel 33 is connected to a vacuum pumping device for vacuumizing the reaction chamber. The vacuum pumping device is a vacuum pump. The gas outlet channel 33 is acted upon by an external vacuum pump to put the growth chamber 3 in a vacuum state, thereby providing necessary conditions for the growth of diamonds.

[0026] The upper cover 13 includes a bottom cover and a top cover arranged on the upper end of the bottom cover. The bottom cover is sealed and connected to the top cover. A medium vacuum sealing ring is arranged between the bottom cover and the top cover. A sealing groove for installing the medium vacuum sealing ring is arranged on the bottom cover. The first condensate water channel 8 is arranged on the bottom cover, and the second condensate water channel 9, the air inlet channel 7, and the window 131 are arranged on the top cover. A diamond seed sheet can be placed on the molybdenum table 5. Reaction gases such as hydrogen and methane enter the reaction chamber through the air inlet channel 7, and are linked to the vacuum pump externally connected to the air outlet channel 33 to maintain a negative pressure environment in the reaction chamber.

[0027] The present application forms a reaction chamber by means of an upper cover 13, a microwave quartz cover 6 and a water-cooling stage 3, and a lower vacuum sealing ring is provided at the connection between the microwave quartz cover 6 and the water-cooling stage 3, and an upper vacuum sealing ring is provided at the connection between the microwave quartz cover and the upper cover, which has a good sealing effect and can effectively isolate the outside air, thereby maintaining the vacuum working environment in the reaction chamber and effectively reducing the vacuum leakage rate, thereby achieving effective isolation of the reaction chamber from the outside air, and providing a favorable guarantee for the preparation of high-quality diamonds.

[0028] The mode converter 2, microwave generator, co-coaxial waveguide 4, rectangular waveguide and circulator used in the utility model are all existing known electrical devices and can be directly purchased and used on the market. Their structures, circuits, and control principles are all existing known technologies. Therefore, the structures, circuits, and control principles of the mode converter 2, microwave generator, co-coaxial waveguide 4, rectangular waveguide and circulator are not described in detail here.

[0029] It should be noted that the above embodiments are only used to illustrate the present utility model, but the present utility model is not limited to the above embodiments. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present utility model fall within the protection scope of the present utility model.

Claims

1. An MPCVD device for diamond growth, characterized in that: The invention comprises a shell (1) having an upper cover (13), a water cooling platform (3) being arranged in the shell (1), a molybdenum platform (5) being arranged at the upper end of the water cooling platform (3), a microwave quartz cover (6) in the shape of a ring being arranged between the water cooling platform (3) and the upper cover (13), the upper cover (13), the microwave quartz cover (6) and the water cooling platform (3) forming a reaction chamber, a plurality of windows (131) being sealedly connected to the upper cover (13) and an air inlet channel (7) communicating with the reaction chamber being arranged on the upper cover (13), the water cooling platform (3) comprising a horizontal portion (34) and a vertical portion (35) extending out of the bottom of the shell (1), an air outlet channel (33) communicating with the reaction chamber being arranged in the water cooling platform (3), and a liquid cooling channel being arranged in the water cooling platform (3), the liquid cooling channel comprising a water inlet channel (31) and a water outlet channel (32).

2. The MPCVD device for diamond growth according to claim 1, characterized in that: The housing (1) comprises a bottom plate (11), a support ring (12) arranged on the bottom plate (11), and an upper cover (13) located at the upper end of the support ring (12).

3. The MPCVD device for diamond growth according to claim 2, characterized in that: The support ring (12) is made of a metal material, and the support ring (12) is provided with a plurality of through holes (121).

4. The MPCVD device for diamond growth according to claim 2, characterized in that: A coaxial waveguide (4) is coaxially sleeved on the outside of the vertical portion (35) at the lower end of the bottom plate (11); the coaxial waveguide (4) is connected to the inside of the housing (1); a mode converter (2) is provided at the lower end of the coaxial waveguide (4); and the mode converter (2) is connected to the microwave system.

5. The MPCVD device for diamond growth according to claim 4, characterized in that: The microwave system comprises a microwave generator, a circulator, a three-pin and a rectangular waveguide which are connected in sequence, and the outlet of the rectangular waveguide is connected to the inlet flange of the mode converter (2), and the microwave transmitted through the rectangular waveguide enters the mode converter (2).

6. The MPCVD device for diamond growth according to claim 4, characterized in that: The right end of the mode converter (2) is connected to a short-circuit piston, and the short-circuit piston is adjustable in sliding left and right directions.

7. The MPCVD device for diamond growth according to claim 1, characterized in that: A lower vacuum sealing ring is provided at the connection between the microwave quartz cover (6) and the water cooling platform (3), and an upper vacuum sealing ring is provided at the connection between the microwave quartz cover (6) and the upper cover (13).

8. The MPCVD device for diamond growth according to claim 1, characterized in that: The upper cover (13) is convex in shape, and a first condensation water channel (8) and a second condensation water channel (9) are also provided on the upper cover (13).

9. The MPCVD device for diamond growth according to claim 1, characterized in that: The gas outlet channel (33) is connected to a vacuum pumping device and is used to vacuumize the reaction chamber.

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