Microwave reaction device

Abstract

The utility model relates to a microwave reaction device, which comprises a growth base platform for placing diamond seed crystals to be grown, and is characterized by further comprising a gasket assembly arranged below the growth base platform, the gasket assembly comprises an upper part and a lower part which are oppositely combined, and an adjusting piece positioned in the center of the lower part, the adjusting piece can enable the upper part to move in the vertical direction relative to the lower part so as to at least change the height of the upper part relative to the growth base station. According to the device, the height of the upper part relative to the growth base table can be at least changed through adjustment of the adjusting piece, fine adjustment of the temperature of the seed crystal can be completed only through one gasket assembly, and the diamond growth quality and efficiency can be improved while proper heat dissipation is kept; the gasket assembly is designed to be of an adjustable structure, so that the current situation that an original traditional gasket cannot be changed is changed, the adjusting mode that the gasket needs to be manually and continuously replaced and a machine is tested is avoided, and finally the production efficiency is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of crystal growth equipment, and more particularly to a microwave reaction device. Background Technology

[0002] Microwave plasma chemical vapor deposition (MPCVD) is a key technology for preparing diamond materials. In this process, ensuring the initial growth temperature of the seed crystal is crucial, directly affecting the quality of the diamond. To ensure uniform temperature distribution, the plasma sphere needs to completely cover the growth platform. Since the height of the plasma sphere remains relatively constant, if the initial growth temperature of the seed crystal is too high, the chemical deposition rate will accelerate, resulting in an excessively thick diamond seed crystal. As the diamond seed crystal thickens, the temperature will also rise accordingly. Once it exceeds the suitable growth temperature range, defects such as blooms, cracks, and cones are likely to occur, all of which reduce the product yield. To lower the temperature, the output power of the microwave power supply can be gradually reduced. However, reducing the microwave power supply power will lead to a decrease in the particle concentration in the plasma sphere, thus affecting the growth of the seed crystal. Conversely, if the initial temperature is too low, the chemical deposition rate will slow down, which is also detrimental to the growth of the seed crystal.

[0003] Typically, the initial temperature of a device is obtained when the microwave power supply is running at full power. Therefore, the temperature cannot be increased by increasing the output power of the microwave power supply. In practice, if a temperature increase is required, the device must be shut down and restarted, which not only affects product quality but also increases labor and time costs.

[0004] To address the aforementioned issues, a microwave reaction device is disclosed in the invention patent "A Microwave Reaction Device for Easily Adjusting Growth Temperature" with patent application number CN202310916192.X (publication number CN116926666A). This device adjusts the distance between the growth base and the growth stage through a lifting mechanism. The higher the height of the growth base and the farther it is from the growth stage, the more the upper surface of the diamond seed crystal enters the high electric field region, and the more energy it obtains from the plasma, thereby achieving the adjustment of the diamond seed crystal growth temperature.

[0005] However, after multiple simulation tests, it was found that the method of adjusting the temperature using a lifting mechanism has certain limitations, namely, the adjustable temperature range is relatively small. Since the height of the plasma sphere remains essentially constant, the growth stage can only be completely covered by the plasma sphere when it is at a specific height. Therefore, when the height of the growth stage is adjusted, the overall temperature of the seed crystal will change, but this change is limited. If the growth stage is too high or too low, it cannot be completely covered by the plasma sphere, which limits the operable temperature range. Therefore, in order to start the growth process, the initial temperature needs to be adjusted to a suitable level first. Currently, the shims under the growth stage are not adjustable, which requires constantly replacing the shims and conducting trial runs when adjusting the initial temperature. This not only reduces start-up efficiency but may also affect the lifespan of the equipment. Utility Model Content

[0006] The first technical problem to be solved by this utility model is to provide a microwave reaction device that can adjust the growth temperature of diamond seed crystals without replacing the gaskets, in light of the above-mentioned existing technology.

[0007] The second technical problem to be solved by this utility model is to provide a microwave reaction device that can stably regulate the growth temperature of diamond seed crystals, in light of the above-mentioned existing technology.

[0008] The technical solution adopted by this utility model to solve the first technical problem mentioned above is as follows: The microwave reaction device includes a growth base for placing the diamond seed crystal to be grown, characterized in that: it further includes a pad assembly disposed below the growth base, the pad assembly includes an upper part and a lower part that are opposite to each other and an adjusting member located in the center of the lower part, the adjusting member can make the upper part move vertically relative to the lower part, thereby changing at least the height of the upper part relative to the growth base.

[0009] To address the second technical problem mentioned above, preferably, the upper portion extends downwards with a first annular wall portion, of which at least two are arranged at intervals from the center to the periphery. The lower portion extends upwards with at least two second annular wall portions, also arranged at intervals from the center to the periphery. Each second annular wall portion is inserted into the interval formed between the first annular wall portions and remains adjacent to each other. Thus, by staggering the first annular wall portions of the upper portion and the second annular wall portions of the lower portion, the upper portion can move smoothly vertically relative to the lower portion without tilting, thereby stabilizing the growth temperature of the diamond seed crystal.

[0010] The adjusting component can have various structures, but from the perspective of cost and space saving, it is preferably a screw. The lower part has a threaded hole for threaded connection with the screw, and the upper part has an abutment portion that abuts against the top of the screw. In its natural state, the top of the screw abuts against the abutment portion. As the screw rotates within the threaded hole and is limited by the various annular portions, the screw can drive the upper part to move vertically in sync. In this way, the height of the gasket assembly can be increased simply by operating the screw, which is convenient and quick.

[0011] Furthermore, the upper part also includes a connecting platform connecting the various first annular wall portions. The growth abutment is disposed on the connecting platform, and the central region of the connecting platform constitutes the abutment portion. Correspondingly, the threaded hole is formed by the first annular wall portion located at the very center of the lower part. By forming the threaded hole in the second annular wall portion located at the very center of the lower part, it is not necessary to open a separate hole as a threaded hole in the lower part, which has the advantage of a simpler structure. At the same time, the upper part, which directly utilizes the portion connecting the various first annular wall portions to form a platform, also serves as a support for the growth abutment on which the diamond seed crystal can be placed, allowing for a more stable connection of the growth abutment.

[0012] To ensure a more stable connection between the upper and lower parts, preferably, the bottom of the outermost second annular wall portion of the lower part extends radially to form a support platform for the outermost first annular wall portion of the upper part, thereby creating a cylindrical structure between the mating upper and lower parts. The support platform in the lower part allows the outermost first annular wall portion of the upper part to rest on the support platform of the lower part, resulting in a cylindrical structure that better matches the shape of the growth substrate, ultimately leading to a more stable connection of the growth substrate.

[0013] Compared with the prior art, the advantages of this utility model are:

[0014] 1. The shim assembly is divided into an upper part, a lower part, and an adjustment component that allows the upper part to move vertically relative to the lower part. The height of the upper part relative to the growth stage can be changed by adjusting the adjustment component. This allows the temperature of the seed crystal to be finely adjusted using only one shim assembly. While maintaining proper heat dissipation, it can improve the quality and efficiency of diamond growth.

[0015] 2. The gasket assembly is designed as an adjustable structure to change the traditional situation where the gasket is not adjustable, thus avoiding the need for manual replacement of gaskets and trial adjustments, and ultimately effectively improving production efficiency. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the gasket assembly in an embodiment of the present invention;

[0017] Figure 2 This is a structural schematic diagram of the gasket assembly from another angle in an embodiment of this utility model;

[0018] Figure 3 This is a schematic diagram of the upper part of the embodiment of the present utility model;

[0019] Figure 4 This is a schematic diagram of the lower part of the embodiment of the present utility model;

[0020] Figure 5 This is a cross-sectional view of the gasket assembly in an embodiment of the present utility model;

[0021] Figure 6 This is a cross-sectional view showing the movement of the upper part of the gasket assembly in an embodiment of this utility model;

[0022] Figure 7 This is an exploded cross-sectional view of the gasket assembly in an embodiment of this utility model. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0024] The microwave reaction apparatus of this embodiment includes a microwave resonant cavity, a growth stage disposed within the microwave resonant cavity, a growth base disposed above the growth stage for placing the diamond seed crystal to be grown, and a pad assembly disposed below the growth base.

[0025] The growth stage is equipped with a water-cooling structure, and the microwave resonant cavity, growth stage and growth base are existing conventional structures. For specific structures, please refer to the growth stage, growth base and cooling mechanism structure connected to the growth stage disclosed in patent application number CN202310916192.X "A Microwave Reaction Device for Easily Adjusting Growth Temperature", which will not be described in detail here.

[0026] The key point of this embodiment is to design the gasket assembly as an adjustable structure, thereby changing the traditional situation where gaskets are not adjustable. This avoids the need for manual gasket replacement and trial adjustments, ultimately effectively improving production efficiency. See details for further reference. Figure 1-7 The shim assembly is divided into an upper part 2, a lower part 1, and an adjustment component that allows the upper part to move vertically relative to the lower part. By adjusting the adjustment component, the height of the upper part 2 relative to the growth stage can be changed. This allows for fine-tuning of the seed crystal temperature using only one shim assembly, improving the quality and efficiency of diamond growth while maintaining proper heat dissipation. The adjustment component is illustrated using screw 3 as an example.

[0027] In this embodiment, the upper part 2 has the following specific structure: the upper part 2 includes four downwardly extending first annular wall portions and a connecting platform 26 connecting each of the first annular wall portions. The four first annular wall portions, which are distributed sequentially from the center to the periphery, are first annular wall portion one 22, first annular wall portion two 23, first annular wall portion three 24 and first annular wall portion four 25. The growth base is located on the connecting platform 26. The interior of the first annular wall portion one 22 in the central area of ​​the connecting platform 26 constitutes the abutment portion 21, which abuts against the top of the screw 3.

[0028] Correspondingly, the specific structure of the lower part 1 is as follows: the lower part 1 extends upward with four second ring wall portions. The four second ring wall portions, which are distributed sequentially from the center to the periphery, are second ring wall portion one 12, second ring wall portion two 13, second ring wall portion three 14 and second ring wall portion four 15. The bottom of the outermost second ring wall portion four 15 extends radially to form a support platform 16 for the outermost first ring wall portion four 25 of the upper part 2 to rest on, so that the upper part 2 and the lower part 1 that are mated together form a cylindrical structure. The second ring wall portion one 12 located at the center constitutes a threaded hole 11 for threaded connection with the screw 3.

[0029] In this embodiment, the upper part 2 is positioned above the lower part 1, and each of the second annular wall parts is inserted into the gap 2a formed between the corresponding two first annular wall parts, maintaining a close proximity to each other. In its natural state, the top of the screw 3 abuts against the abutment part 21, and as the screw 3 rotates within the threaded hole 11 and is limited by the respective annular parts, the screw 3 can drive the upper part 2 to move synchronously upwards.

[0030] The specific dimensions of the gasket assembly are as follows: the overall thickness of the upper part 2 is 6mm, the height of each of the four first ring walls is 4mm, the diameter of the abutment part 21 is 12mm, and the depth is 4mm; the overall thickness of the lower part 1 is 6mm, the height of each of the four second ring walls is 4mm, and the diameter of the threaded hole 11 is 7mm; the screw 3 is a recessed set screw with a specification of M8*6mm, which controls the contact area and height between the lower part 1 and the upper part 2 by rotating and raising.

[0031] like Figure 6As shown, with screw 3 rotating within threaded hole 11, upper part 2 moves synchronously with screw 3. Screw 3 drives upper part 2 to move vertically relative to lower part 1. Thus, by raising and lowering the height of upper part 2, the contact area between upper part 2 and lower part 1 is changed, thereby at least altering the height of upper part 2 relative to the growth stage. This allows the operator to precisely control the heat exchange efficiency between the seed crystal and the growth stage. Furthermore, because upper part 2 and lower part 1 are staggered like comb strips and always remain adjacent to each other, even when upper part 2 moves upward, it will not tilt, ensuring the seed crystal remains on the same horizontal plane. The rising range of upper part 2 is 0-4mm, and typically does not exceed 3mm.

[0032] In this embodiment, the initial state of the gasket assembly is that the upper part 2 and the lower part 1 are completely overlapped. By screwing the screw 3 into the threaded hole 11, the gasket assembly is formed into a cylindrical gasket with a diameter of 60mm and a height of 8mm. At this point, the contact area is maximized, the heat dissipation performance is optimal, and the initial temperature of the seed crystal is lowest. In this state, the temperature of the seed crystal can be maintained at around 800 degrees Celsius. Subsequently, as the screw 3 is rotated, the upper part 2 is gradually lifted up, creating a gap with the lower part 1. Experiments show that for every 0.1mm increase in the upper part 2, the temperature of the seed crystal increases by 20 degrees Celsius. When the misalignment between the upper part 2 and the lower part 1 is at its maximum, the contact area is minimized, the heat dissipation efficiency decreases, and the initial temperature of the seed crystal is highest. Therefore, by rotating the screw 3, the initial temperature of the seed crystal can be precisely controlled.

Claims

1. A microwave reaction apparatus, comprising a growth platform for placing a diamond seed crystal to be grown, characterized in that: It also includes a pad assembly disposed below the growth substrate, the pad assembly including an upper part (2) and a lower part (1) that are opposite to each other and an adjustment member located in the center of the lower part (1), the adjustment member enabling the upper part (2) to move vertically relative to the lower part (1), thereby changing at least the height of the upper part (2) relative to the growth substrate; The upper part (2) extends downward with a first ring wall portion, which has at least two parts, and is distributed in sequence from the center to the periphery. The lower part (1) extends upward with at least two second ring wall portions, which are also distributed in sequence from the center to the periphery. Each second ring wall portion is inserted into the gap (2a) formed between the first ring wall portions and remains in close proximity to each other.

2. The microwave reaction apparatus according to claim 1, characterized in that: The adjusting component is a screw (3). The lower part (1) has a threaded hole (11) that is threadedly connected to the screw (3). The upper part (2) has an abutting part (21) that abuts against the top of the screw (3). In its natural state, the top of the screw (3) abuts against the abutting part (21). When the screw (3) rotates in the threaded hole (11) and is limited by each annular part, the screw (3) can drive the upper part (2) to move vertically in sync.

3. The microwave reaction apparatus according to claim 2, characterized in that: The upper part (2) also includes a connecting platform (26) that connects each of the first ring wall portions. The growth base is disposed on the connecting platform (26). The central area of ​​the connecting platform (26) constitutes the abutment portion (21). Correspondingly, the threaded hole (11) is formed by the second ring wall portion located at the center of the lower part (1).

4. The microwave reaction apparatus according to claim 3, characterized in that: The bottom of the outermost second ring wall of the lower part (1) extends radially to form a support platform (16) for the outermost first ring wall of the upper part (2) to rest, thereby forming a cylindrical structure between the upper part (2) and the lower part (1) that are joined together.

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