A deposition chamber structure and MPCVD apparatus

Abstract

The application relates to a deposition chamber structure and an MPCVD device, and belongs to the field of diamond synthesis devices. The technical scheme is as follows: a deposition chamber structure comprises a base, a tubular quartz window is fixedly arranged on the base, an upper cover is sealingly connected above the quartz window, a metal ring is arranged outside the quartz window, a plurality of horizontally arranged and vertically arranged microwave feeding slits are arranged in the middle region of the metal ring, a resonant metal cavity is arranged outside the middle region of the metal ring, the resonant metal cavity is used for being connected with a microwave source, a growth base capable of multi-stage lifting is arranged in the quartz window, the dimension of microwave feeding is increased, a discharge area is coupled above the growth base to form a plasma with the characteristics of large size, uniform stability and high energy density, the growth base can be lifted in multiple stages, the deposition quality of a growth sample is optimized, the deposition area of the growth sample is expanded, and preparation of a high-quality large-size diamond crystal is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of diamond synthesis equipment, in particular to a deposition chamber structure and an MPCVD equipment. BACKGROUND

[0002] Microwave plasma chemical vapor deposition (MPCVD) has become the optimal chemical vapor deposition method for artificial synthesis of diamond due to its high energy density, no internal electrode pollution in the reaction chamber, multiple types of process gas, continuous and stable controllable microwave power, stable controllable growth temperature field, high purity of grown diamond crystal, and low defect density.

[0003] MPCVD utilizes microwave energy to excite gas molecules containing diamond precursors mainly in the form of hydrogen and methane, producing high-concentration plasma, which cracks methane and hydrogen into free carbon radicals and various ions at several thousand degrees Celsius. In this process, the plasma not only realizes the preparation of diamond growth raw materials, but also provides driving force for the stable transmission of free carbon active groups.

[0004] Existing MPCVD equipment mainly has two chamber structures, cylindrical cavity structure and disc-shaped cavity structure. In the cylindrical cavity structure, the microwave enters the reaction chamber from above the cavity to form a plasma sphere. In the disc-shaped cavity structure, the microwave enters the reaction chamber from below the cavity to form a plasma sphere. Due to the limitations of chamber shape structure, microwave feeding method, microwave energy density, microwave discharge area, and poor stability of microwave plasma, it is difficult to prepare large-size diamond crystals with high quality, and it is difficult to meet the application requirements of users for high-quality large-size diamond crystals. SUMMARY

[0005] To solve the technical problem that the existing MPCVD equipment chamber structure is difficult to couple to obtain plasma with higher energy density, larger discharge area, uniform stability, and less jump, which leads to the inability to prepare large-size diamond crystals with high quality, the present application provides a deposition chamber structure.

[0006] The technical scheme of the present application is as follows:

[0007] The application provides a deposition chamber structure, which comprises a base, a tubular quartz window fixed on the base, an upper cover sealingly connected above the quartz window, a metal ring sleeved outside the quartz window, a plurality of horizontally arranged and vertically arranged microwave feed slots arranged in the middle region of the metal ring, a resonant metal cavity sleeved outside the middle region of the metal ring, the resonant metal cavity being used for being connected with a microwave source, and a growth pedestal capable of being lifted in multiple stages arranged in the quartz window. The horizontally arranged microwave feed slots are distributed in the circumferential direction of the metal ring, one vertically arranged microwave feed slot is arranged between every two adjacent horizontally arranged microwave feed slots, the vertically arranged microwave feed slots are arranged on the side of the metal ring away from the microwave source, the horizontally arranged and vertically arranged microwave feed slots increase the dimension of microwave feeding, thereby improving the uniformity of microwave distribution in the resonant metal cavity and the quartz window as a whole, the vertically arranged microwave feed slots are arranged on the side of the metal ring away from the microwave generating device, the microwave can be better coupled from the resonant metal cavity into the quartz window, the microwave is better matched with the electromagnetic field in the quartz window, the reflection and energy loss are reduced, thereby the coupling efficiency of the microwave is improved, the deposition quality of the growth sample is optimized, the deposition area of the growth sample is expanded, the deposition rate of the growth sample is improved, and the preparation of a high-quality large-size diamond crystal is realized.

[0008] Preferably, a plurality of heat dissipation holes are uniformly arranged on the circumferential side of the upper and lower end regions of the metal ring, a forced air cooling channel is arranged around the lower end region of the resonant metal cavity and the lower end region of the metal ring, the heat generated by the metal ring and the resonant metal cavity during work can be efficiently taken away, the performance of the material is prevented from being reduced due to excessively high temperature, thereby the stability and reliability of the entire deposition chamber structure are ensured, and the service life of the equipment is prolonged.

[0009] Preferably, a bottom plate is fixed on the upper cover, a vertically arranged first stroke rod is fixedly installed on the bottom plate, a first limiting plate is fixedly arranged at the top end of the first stroke rod, a movement module is slidingly connected with the first stroke rod, a metal column is fixedly connected to the bottom of the movement module, a first sealing spring bellows is sleeved outside the metal column and fixed between the bottom plate and the movement module, the sealing property of the metal column during movement is ensured, gas leakage in the chamber is avoided, the metal column is used for moving and being inserted into the quartz window, the upper end of the metal column is used for being connected with a bias power module, appropriate bias can be applied to the environment in the chamber, the reaction process is controlled, and the quality and efficiency of diamond crystal deposition are improved.

[0010] Preferably, a second stroke rod is fixed on the movement module, the upper end of the second stroke rod passes through the first limiting plate, and the second limiting plate is fixedly connected, and the first screw rod is threadedly connected to the second limiting plate; the movement module is also fixedly provided with a probe electrode in sealing connection with the metal column, the lower end of the first screw rod is used for passing through the first limiting plate and being connected or separated from the probe electrode, the upper end of the first screw rod is connected with the bias power module, the position of the first screw rod can be adjusted according to requirements, and then the metal column and the bias power module can be connected through the first screw rod and the probe electrode, so that the connection requirements of the metal column and the bias power module at different positions are met, the electromagnetic field distribution in the deposition process is optimized, and high-quality diamond crystals are beneficial to preparation.

[0011] Preferably, the movement module, the upper cover, the base and the growth pedestal are all internally provided with cooling water pipelines, effective cooling can be performed, the working temperature of components is stably maintained, the equipment performance and the diamond crystal deposition quality are prevented from being affected by temperature fluctuation, a stable temperature environment helps to reduce mechanical stress caused by thermal expansion and cold contraction of components, and the overall service life of the equipment is prolonged.

[0012] Preferably, the growth pedestal is fixedly installed on the secondary lifting disc, the upper end of the growth pedestal passes through the sealing ring and the base in sequence and extends into the quartz window, the lower side of the sealing ring is fixedly connected with the primary lifting disc through the third stroke rod, the secondary lifting disc is in sliding connection with the third stroke rod, the primary lifting disc is connected with the primary lifting motor, the primary lifting motor is fixedly installed on the rack, the secondary lifting disc is connected with the secondary lifting motor, and the secondary lifting motor is installed on the primary lifting disc; the primary lifting disc can be quickly lifted in a large range, and the requirement of adjusting the approximate position of the growth pedestal is met; the secondary lifting disc can realize fine lifting adjustment with high precision, the height of the growth pedestal can be accurately adjusted according to different crystal growth stages in combination with the uniformity advantage of microwave distribution, the crystal growth environment is optimized, and the deposition quality and size of the diamond crystal are improved.

[0013] Preferably, the second sealing spring bellows is fixed between the sealing ring and the secondary lifting disc, the second sealing spring bellows covers the area of the growth pedestal below the sealing ring, the sealing property of the chamber is ensured, and external gas is prevented from entering the deposition chamber to interfere with the crystal growth process; meanwhile, the second sealing spring bellows can automatically expand and contract with the growth pedestal, does not hinder the movement of the growth pedestal, and ensures stable operation of the equipment.

[0014] Preferably, the lifting speed of the primary lifting disc is 1-100 mm / min, and the lifting speed of the secondary lifting disc is 0.1-1000 μm / min; the lifting speed range of the primary lifting disc can quickly adjust the growth pedestal to a suitable approximate area, and the operation efficiency is improved; the very small lifting speed change range of the secondary lifting disc can realize fine adjustment of the height of the growth pedestal, meets the requirement of high-precision control of the growth environment in the diamond crystal growth process, and is thus beneficial to preparation of high-quality and large-size diamond crystals.

[0015] Preferably, the included angle between two adjacent transversely arranged microwave feed slots is 60°-120°, the transversely arranged microwave feed slots can better cooperate with the vertically arranged microwave feed slots, further optimize the uniformity of the distribution of the microwave in the resonant metal cavity and the quartz window, enhance the matching degree of the microwave and the electromagnetic field in the cavity, effectively reduce the microwave reflection and energy loss, improve the microwave coupling efficiency, and ultimately improve the deposition quality and deposition rate of the diamond crystal.

[0016] The present application provides a kind of MPCVD equipment, uses the deposition chamber structure described above.

[0017] From the above technical solution, the advantages of the present application are as follows:

[0018] After the microwave is transmitted to the resonant metal cavity by the microwave source and resonates, it is uniformly and stably fed into the vacuum quartz window through the transverse and vertical microwave feed slots on the metal ring, and a large, uniform and stable plasma with high energy density is coupled to form a discharge area above the growth base. At the same time, a positive bias electric field is connected to the top of the chamber, which further optimizes the plasma state and makes the plasma more flat and uniform. The nucleation quality, crystal quality and growth rate of the growth sample are greatly improved. The growth base is multi-stage lifting, so as to control the height of the growth base during the growth and deposition process. The microwave feed-in mode combined with the height adjustment of the growth base, together with the positive bias electric field connected to the top of the chamber, optimizes the deposition quality of the growth sample, expands the deposition area of the growth sample, and improves the deposition rate of the growth sample. The preparation of high-quality large-size diamond crystal is realized. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the present application, the drawings needed in the description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0020] Figure 1 The overall structure of the deposition chamber structure according to one or more embodiments of the present application is shown in the figure.

[0021] Figure 2 The structure of the metal ring according to one or more embodiments of the present application is shown in the figure. Figure 1 ;

[0022] Figure 3 The structure of the metal ring according to one or more embodiments of the present application is shown in the figure. Figure 2 ;

[0023] The components represented by the reference numerals in the figure are:

[0024] 1, bottom plate; 2, first stroke rod; 3, first limit plate; 4, movement module; 5, first sealing spring bellows; 6, metal column; 7, second stroke rod; 8, second limit plate; 9, probe electrode; 10, first screw rod; 11, upper cover; 12, infrared temperature observation hole; 13, quartz window; 14, metal ring; 15, heat dissipation hole; 16, microwave feed gap; 17, resonant metal cavity; 18, air cooling channel; 19, base; 20, sealing ring; 21, growth base; 22, second sealing spring bellows; 23, two-stage lifting disc; 24, second screw rod; 25, two-stage lifting motor; 26, third stroke rod; 27, one-stage lifting disc; 28, lifting frame; 29, one-stage lifting motor; 30, fourth stroke rod; 31, rack. DETAILED DESCRIPTION

[0025] In order to make the purpose, features and advantages of the present application more obvious and easy to understand, the technical solutions in the present application will be described clearly and completely below in combination with the drawings in the specific embodiments. Obviously, the following described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present patent, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present patent.

[0026] Embodiment 1

[0027] In a typical embodiment of the present application, as Figure 1As shown, a deposition chamber structure is proposed, comprising: an upper cover 11, a quartz window 13, a metal ring 14, a resonant metal cavity 17, a base 19 and a growth pedestal 21, the base 19 is fixedly installed on a rack 31, the tubular quartz window 13 is a microwave feed window and a chamber vacuum pressure retaining component, the height of the quartz window 13 is 200-300 mm, the thickness of the tube wall is 1-5 mm, the quartz window 13 is placed on the base 19, the upper cover 11 is placed on the quartz window 13 to contact and seal, the side of the upper cover 11 is provided with an infrared temperature observation hole 12 for infrared exploration of temperature, the upper and lower ends of the quartz window 13 and the contacting base 19 and upper cover 11 are sealed and fixed by fluorine rubber rings, so as to facilitate the subsequent vacuum operation in the quartz window 13, the metal ring 14 is sleeved outside the quartz window 13, the metal ring 14 and the quartz window 13 are coaxially arranged, the lower end of the metal ring 14 is fixedly connected with the base 19 by screws, the upper end of the metal ring 14 is fixedly connected with the upper cover 11 by screws, the upper and lower end regions of the metal ring 14 are uniformly provided with a plurality of heat dissipation holes 15 on the circumferential side, the heat dissipation holes 15 are uniformly and densely distributed straight holes and / or inclined holes with a hole diameter of 1-3 mm, the distribution density of the heat dissipation holes 15 is 4-12 pieces / cm², the circumferential side of the middle region of the metal ring 14 is provided with a plurality of microwave feed slots 16; the resonant metal cavity 17 is sleeved outside the middle region of the metal ring 14, the resonant metal cavity 17 and the metal ring 14 form a resonant chamber, the resonant metal cavity 17 is used to be connected with a rectangular microwave waveguide pipe, and then connected with a microwave source, the microwave power adjustment range of the microwave source is 0.6-12 KW, the frequency is 2.45 GHz or 915 MHz, the lower side of the resonant metal cavity 17 and the lower end region of the metal ring 14 are surrounded by a cooling channel 18, and the cooling channel 18 is connected with a cooling fan for air cooling work, the air volume of the cooling fan is 5-30 m³ / h; the growth pedestal 21 is vertically arranged in the quartz window 13, and the vertical position of the growth pedestal 21 in the quartz window 13 can be changed according to requirements to adapt to different working requirements.

[0028] Specifically as Figure 2 and Figure 3As shown, the microwave feed-in slots 16 are provided in several numbers, and the several microwave feed-in slots 16 are divided into two kinds of transverse arrangement and vertical arrangement, wherein the microwave feed-in slots 16 arranged transversely are distributed along the circumferential direction of the metal ring 14, the microwave feed-in slots 16 arranged transversely are 50 mm long and 3 mm wide, and the included angle between two adjacent microwave feed-in slots 16 arranged transversely is 60°-120° (central angle).

[0029] The microwave feed-in slots 16 are divided into two kinds of transverse and vertical arrangement, which can obtain plasma with higher energy density, larger discharge area, and better uniformity and stability. Specifically, the microwave feed-in slots 16 arranged transversely are arranged along the circumferential direction of the metal ring 14, which can make the microwave be fed in more uniformly in the circumferential direction of the metal ring 14, and one microwave feed-in slot 16 arranged vertically is arranged between every two adjacent microwave feed-in slots 16 arranged transversely, which further increases the dimension of microwave feeding, so that the microwave can also be distributed more uniformly in the radial direction of the metal ring 14, thereby enhancing the distribution uniformity of the microwave in the resonant metal cavity 17 and the quartz window 13 as a whole, which is conducive to improving the consistency of the process at the growth base 21 in the quartz window 13, and the microwave feed-in slots 16 arranged vertically are located on the side of the metal ring 14 away from the microwave generating device, which can better guide the microwave to be coupled from the resonant metal cavity 17 into the quartz window 13, make the microwave better match the electromagnetic field in the quartz window 13, reduce reflection and energy loss, thereby improve the coupling efficiency of the microwave, so that more microwave energy can effectively act on the substance on the growth base 21, improve the process efficiency and quality.

[0030] The growth stage 21 consists of a molybdenum sample stage and a water-cooled copper substrate stage, enabling the production of homogeneous or heterogeneous epitaxial diamond thin films and thick films on 1-4 inch diamond substrates at a growth rate of 0.1-100 μm / h. In this embodiment, the growth stage 21 has a multi-stage lifting structure, allowing its vertical height to be adjusted according to actual needs. Specifically, the growth stage 21 is fixedly mounted on a multi-stage lifting drive mechanism, which includes a second sealed spring bellows 22, a second-stage lifting plate 23, a second screw 24, a second-stage lifting motor 25, a third stroke rod 26, a first-stage lifting plate 27, a lifting frame 28, a first-stage lifting motor 29, and a fourth stroke rod 30. The first-stage lifting motor 29 is fixedly mounted on the frame 31, and its output end is fixedly connected to a drive screw. The drive screw is connected to the lifting frame. The lifting frame 28 is connected by a threaded connection, with the drive screw set vertically. The first-stage lifting motor 29 can drive the lifting frame 28 to move vertically via the drive screw. To limit the rotation of the lifting frame 28 around its axis, the lifting frame 28 is also slidably connected to the fourth stroke rod 30 set vertically. The first-stage lifting plate 27 is fixedly mounted on the lifting frame 28 and can move vertically with the lifting frame 28. The second-stage lifting motor 25 is vertically fixedly mounted on the first-stage lifting plate 27. The output end of the second-stage lifting motor 25 is fixedly connected to the second screw 24 to drive the second screw 24 to rotate around its axis. The second-stage lifting plate 23 is threadedly connected to the second screw 24, and the second-stage lifting plate 23 is also slidably connected to the third stroke rod 26 set vertically. Thus, under the drive of the second-stage lifting motor 25 and the second screw 24, the second-stage lifting plate 23 can move vertically in two stages.

[0031] Specifically, such as Figure 1 As shown, the primary lifting motor 29 is connected to the lifting frame 28, and the primary lifting plate 27 is installed and fixed on the lifting frame 28. The upper end of the fourth stroke rod 30 is fixedly connected to the base 19, and the lower end of the fourth stroke rod 30 is fixedly connected to the frame 31. The bottom of the base 19 is provided with a sealing ring 20 to ensure the sealing between the base 19 and the growth base 21. The fourth stroke rod 30 passes vertically through the sealing ring 20 and the edge of the primary lifting plate 27. The movement of the primary lifting motor 29 drives the lifting frame 28 to rise and fall, and the lifting frame 28 drives the primary lifting plate 27 to rise and fall within a certain range of the fourth stroke rod 30.

[0032] The inner side of the fourth stroke rod 30 above the first lifting disc 27 is fixedly provided with a third stroke rod 26, the upper end of the third stroke rod 26 is fixed to the lower side of the sealing ring 20, the lower end of the third stroke rod 26 is fixedly connected with the first lifting disc 27, the second lifting disc 23 is slidingly arranged on the third stroke rod 26, the second sealing spring bellows 22 is fixedly arranged between the sealing ring 20 and the second lifting disc 23, the second sealing spring bellows 22 is used for surrounding the lower region of the growth pedestal 21 (i.e. the region below the sealing ring 20), specifically, the growth pedestal 21 is fixedly arranged on the second lifting disc 23, the upper end of the growth pedestal 21 passes through the sealing ring 20 and the base 19 in sequence and extends into the quartz window 13, the second lifting motor 25 drives the second screw rod 24 to rotate, the second screw rod 24 drives the second lifting disc 23 to ascend and descend, and the second lifting disc 23 drives the growth pedestal 21 to ascend and descend.

[0033] In the embodiment, the stroke range of the first lifting disc 27 is 0-500 mm, and the ascending and descending speed is 1-100 mm / min; the ascending and descending speed of the second lifting disc 23 is 0.1-1000 μm / min, the height of the growth pedestal 21 is controlled in the range of 0-100 mm, and the control precision is 1 μm.

[0034] The crystal growth efficiency can be effectively improved, the height of the growth pedestal 21 is dynamically adjusted with the increase of the height of the sample substrate during the growth process, unnecessary power-on and power-off operations caused by replacement of different height pads are reduced, the service life of the equipment is prolonged, the growth continuity and uniformity of the same sample substrate are ensured, and the crystal quality is well guaranteed.

[0035] The upper cover 11 is further fixedly provided with a bias device, so as to access a positive bias electric field above the chamber, optimize the deposition quality of the growth sample, expand the deposition area of the growth sample, improve the deposition rate of the growth sample, and realize preparation of high-quality large-size diamond crystals.

[0036] Specifically, the biasing device comprises a bottom plate 1, a first stroke rod 2, a first limiting plate 3, a movement module 4, a first sealing spring bellows 5, a metal column 6, a second stroke rod 7, a second limiting plate 8, a probe electrode 9 and a first screw rod 10, the bottom plate 1 is made of metal, the bottom plate 1 is fixedly installed on the upper cover 11 through screws, the first stroke rod 2 is provided with two, the two first stroke rods 2 are vertically fixedly arranged on the bottom plate 1, the movement module 4 is made of metal, the two ends of the movement module 4 are slidably connected with the adjacent first stroke rods 2, the top ends of the two first stroke rods 2 are fixedly connected through the first limiting plate 3, and the first stroke rod 2 and the first limiting plate 3 are fixedly welded; the metal column 6 is a molybdenum metal cylinder, the metal column 6 is vertically fixedly arranged at the center position of the bottom of the movement module 4, the lower end of the metal column 6 sequentially penetrates the center position of the bottom plate 1 and the upper cover 11 and extends into the quartz window 13, the first sealing spring bellows 5 is sleeved outside the metal column 6, the upper end of the first sealing spring bellows 5 is fixedly connected with the movement module 4, and the lower end of the first sealing spring bellows 5 is fixedly connected with the bottom plate 1, so as to seal the part of the metal column 6 between the bottom plate 1 and the movement module 4, the movement module 4 is used for guiding when the metal column 6 extends into the quartz window 13, and it is guaranteed that the metal column 6 can move vertically.

[0037] The second stroke rod 7 is provided with two, the two second stroke rods 7 are vertically fixedly arranged on the movement module 4, the lower end of the second stroke rod 7 is fixedly connected with the movement module 4 through welding, the upper end of the second stroke rod 7 penetrates the first limiting plate 3, the upper ends of the two second stroke rods 7 are fixedly connected through the second limiting plate 8, the second stroke rod 7 and the second limiting plate 8 are fixedly welded, the first screw rod 10 is threadedly connected with the second limiting plate 8, and the lower end of the first screw rod 10 penetrates the first limiting plate 3; the probe electrode 9 is fixedly arranged above the movement module 4, and the probe electrode 9 is sealingly connected with the metal column 6, the lower end of the first screw rod 10 is used for being connected with the probe electrode 9 and being connected with the metal column 6 through the probe electrode 9, and the upper end of the first screw rod 10 is used for being connected with a biasing power module, so that a 50-100V positive electric field is applied to the microwave plasma.

[0038] In the embodiment, the air cooling channel 18, the metal ring 14, the resonant metal cavity 17, the base 19, the sealing ring 20, the first-stage lifting disc 27 and the second-stage lifting disc 23 are all made of aluminum alloy; the movement module 4, the upper cover 11, the base 19 and the growth base 21 are all internally provided with a cooling water pipeline, the cooling water pipeline is connected with a cooling water circulation air conditioner, the cooling water has a temperature of 10-35℃, the cooling water in the cooling water pipeline has a temperature control range of 10-35℃, the control precision is 0.1℃, the cooling water flow is greater than or equal to 40L / min, and the flow and the temperature can be controlled through the overall external cooling water circulation air conditioner.

[0039] Embodiment 2

[0040] In another typical embodiment of the present application, an MPCVD device is provided, which adopts the deposition chamber structure mentioned in embodiment 1.

[0041] The process of depositing diamond film on a 10mm*10mm diamond single crystal substrate using the deposition chamber structure is as follows:

[0042] When the sealing ring 20 is in close contact with the base 19, the primary lifting plate 27 is operated to the upper limit of the stroke, and the primary lifting motor 29 stops running. Then the secondary lifting motor 25 is operated to drive the second screw rod 24 to rotate, and the second screw rod 24 rotates to drive the secondary lifting plate 23 to rise to compress the second sealing spring bellows 22, so as to lift the growth pedestal 21 to the inside of the quartz window 13.

[0043] The 10mm*10mm diamond single crystal substrate is placed at the center of the growth pedestal 21, and the upper cover 11 together with the bias device above it is sealed and fixed above the metal ring 14 by screws. The vacuum pump of the MPCVD device is operated to evacuate the quartz window 13. As the pressure in the quartz window 13 gradually decreases, the atmospheric pressure compresses the first sealing spring bellows 5 downward, and as the first sealing spring bellows 5 is gradually compressed, the metal column 6 connected with the probe electrode 9 is pressed into the inside of the quartz window. After the vacuum is finished, the first sealing spring bellows 5 is completely compressed, the metal column 6 connected with the probe electrode 9 stops moving, the first screw rod 10 above the movement module 4 is rotated, the lower end of the first screw rod 10 is pressed against the probe electrode 9, and the upper end of the first screw rod 10 is connected with the bias power supply module.

[0044] The cooling water circulation air conditioner is operated to set the cooling circulating water temperature to 10-35℃, the cooling water flow rate to ≥40L / min, and the air volume of the cooling fan to 5-30m³ / h. The growth atmosphere is mixed in proportion, the chamber pressure is adjusted to 10-250 Torr, the microwave source is operated, the microwave power is adjusted to 0.6KW-12KW, the bias power supply module is operated, and the positive bias is set to 50-100V.

[0045] As the growth process advances, the height of the growth sample is continuously increased, and the multi-stage lifting drive mechanism is operated to control the lifting of the growth pedestal 21, so that the growth sample is always in the best position. The height of the growth pedestal 21 is controlled in the range of 0-100mm, and the control accuracy is 1μm.

[0046] In this embodiment, the microwave is transmitted from the microwave source to the resonant metal cavity 17 through the rectangular waveguide, and after resonance, it is uniformly and stably fed into the quartz window 13 in the vacuum through the microwave feeding slots 16 on the metal ring 14. The discharge area is large, uniform and stable, and the energy density is high. The plasma is coupled above the growth base 21 to form a large, uniform and stable plasma with high energy density. A positive bias electric field is connected to the top of the chamber to further optimize the plasma state, making the plasma more flat and uniform. The nucleation quality, crystal quality and growth rate of the growth sample are greatly improved. The growth base 21 is installed and fixed on the multi-stage lifting driving mechanism to adjust the height of the growth base 21 during the growth and deposition process. Through the new microwave feeding mode, combined with the height adjustment of the growth base 21, and the positive bias electric field connected to the top of the chamber, the deposition quality of the growth sample is optimized, the deposition area of the growth sample is expanded, and the deposition rate of the growth sample is improved. The preparation of high-quality large-size diamond crystal is realized.

[0047] The above description of disclosed embodiments enables one of ordinary skill in the art to make or use the application. Various modifications to these embodiments will be readily apparent to those of ordinary skill in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. Accordingly, the application is not to be limited to the embodiments shown herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

1. A deposition chamber structure, comprising: The base (19) is fixed with a tubular quartz window (13), and the upper cover (11) is sealingly connected above the quartz window (13), characterized in that the outer side of the quartz window (13) is sleeved with a metal ring (14), the middle region of the metal ring (14) is provided with a plurality of horizontally arranged and vertically arranged microwave feed slots (16), the outer side of the middle region of the metal ring (14) is sleeved with a resonant metal cavity (17), the resonant metal cavity (17) is used for being connected with a microwave source, and the quartz window (13) is provided with a growth base (21) capable of multi-stage lifting. The horizontally arranged microwave feed slots (16) are distributed along the ring direction of the metal ring (14) at intervals, one vertically arranged microwave feed slot (16) is arranged between every two adjacent horizontally arranged microwave feed slots (16), the vertically arranged microwave feed slot (16) is located on the side of the metal ring (14) away from the microwave source, and the included angle between the two adjacent horizontally arranged microwave feed slots (16) is 60°-120°.

2. The deposition chamber structure of claim 1, wherein, The upper and lower end regions of the metal ring (14) are uniformly provided with a plurality of heat dissipation holes (15) on the circumferential side, and the lower side of the resonant metal cavity (17) and the lower end region of the metal ring (14) are surrounded by a forced air cooling channel (18).

3. The deposition chamber structure of claim 1, wherein, The upper cover (11) is fixed with a bottom plate (1), the bottom plate (1) is fixedly installed with a vertically arranged first stroke rod (2), the top end of the first stroke rod (2) is fixed with a first limiting plate (3), the first stroke rod (2) is slidingly connected with a movement module (4), the bottom of the movement module (4) is fixedly connected with a metal column (6), the outer side of the metal column (6) is sleeved with a first sealing spring bellows (5), the first sealing spring bellows (5) is fixedly arranged between the bottom plate (1) and the movement module (4), the metal column (6) is used for being movably inserted into the quartz window (13), and the upper end of the metal column (6) is used for being connected with a bias power supply module.

4. The deposition chamber structure of claim 3, wherein, The movement module (4) is fixedly provided with a second stroke rod (7), the upper end of the second stroke rod (7) penetrates through the first limiting plate (3) and is fixedly connected with a second limiting plate (8), and the second limiting plate (8) is threadedly connected with a first screw rod (10); the movement module (4) is further fixedly provided with a probe electrode (9) sealingly connected with the metal column (6), the lower end of the first screw rod (10) is used for penetrating through the first limiting plate (3) and being connected with or separated from the probe electrode (9), and the upper end of the first screw rod (10) is connected with the bias power supply module.

5. The deposition chamber structure of claim 3, wherein, The interiors of the movement module (4), the upper cover (11), the base (19) and the growth base (21) are all provided with cooling water pipelines.

6. The deposition chamber structure of claim 1, wherein, The growth pedestal (21) is fixedly installed on the secondary lifting disc (23), the upper end of the growth pedestal (21) extends into the quartz window (13) through the sealing ring (20) and the base (19) in sequence, the lower side of the sealing ring (20) is fixedly connected with the primary lifting disc (27) through the third stroke rod (26), the secondary lifting disc (23) is slidably connected with the third stroke rod (26), the primary lifting disc (27) is connected with the primary lifting motor (29), the primary lifting motor (29) is fixedly installed on the rack (31), the secondary lifting disc (23) is connected with the secondary lifting motor (25), and the secondary lifting motor (25) is installed on the primary lifting disc (27).

7. The deposition chamber structure of claim 6, wherein, The second sealing spring bellows (22) is fixedly arranged between the sealing ring (20) and the secondary lifting disc (23) and covers the area of the growth pedestal (21) below the sealing ring (20).

8. The deposition chamber structure of claim 6, wherein, The lifting speed of the primary lifting disc (27) is 1-100 mm / min, and the lifting speed of the secondary lifting disc (23) is 0.1-1000 μm / min.

9. An MPCVD apparatus, characterized by, The deposition chamber structure according to any one of claims 1-8 is adopted.

Images