Diamond growth molybdenum ring

Abstract

The invention relates to the field of vapor deposition, and discloses a diamond growth molybdenum ring which is characterized in that the diamond growth molybdenum ring comprises a molybdenum ring body, and a through hole is formed in the molybdenum ring body; the molybdenum ring body is provided with a through hole, the through hole is used for being externally connected with diamond substrates of different sizes so that the four side edges of each diamond substrate can make contact with the inner wall of the through hole, and the through hole is in a central symmetry shape formed by orthogonality of two identical ellipses. The diamond substrate is in linear contact, so that heat dissipation conditions of side edges of the diamond substrate are similar, heat dissipation uniformity of the diamond substrate in the side edge direction is improved, continuous variable diamond substrates of different sizes can be placed, the overall temperature distribution of the substrate is uniform in the diamond growth process, and the service life of the substrate is prolonged. And other problems in the diamond growth process are solved, and the method has great significance for researching the growth of high-quality diamond.

Description

Technical Field

[0001] The invention relates to the field of vapor deposition, and more particularly to a diamond-growing molybdenum ring. Background Art

[0002] Diamond has outstanding physical and chemical properties, such as high hardness, high thermal conductivity (2000W·m-1·K-1 at room temperature), wide bandgap (5.47eV), high mobility, high transmittance and wide transmittance range. It is not only widely used in traditional mechanical processing, heat sinks, vacuum / optical windows and other industrial applications, but also has potential application value in cutting-edge technology fields such as quantum computing, radiation / ultraviolet detection, integrated circuit power devices, etc.

[0003] Microwave plasma chemical vapor deposition (MPCVD) is an ideal method for preparing artificial diamonds. Compared with the high temperature and high pressure method, the grown CVD diamonds are of better purity and larger size, which is conducive to the development of large-size high-quality diamond applications. In the microwave method, microwaves are usually used as an energy source to excite gases such as CH4 and H2 into a plasma state to form a stable plasma ball, and then the grown diamonds are deposited on the substrate. The MPCVD method has the advantages of non-polar discharge, less pollution, and large-area diamond preparation. Its products are widely used in the jewelry industry and high-tech fields such as semiconductors.

[0004] In the deposition chamber after the plasma is stabilized, the heat distribution is very uneven, and the temperature is roughly the highest point in the center of the plasma and decreases in a gradient to the surrounding areas. Temperature is an important factor affecting the deposition of diamond grains, because temperature affects the absorption rate of impurities, which in turn affects the uniformity of the growth layer. Uneven temperature can also cause problems such as crystal morphology, growth rate and cracking. Therefore, it is necessary to select a substrate with a flat surface before growth to obtain a good contact area with the substrate holder to ensure heat dissipation. However, in fact, the surface of the substrate is not a completely flat plane, and the surface directly in contact with the substrate holder is still not tightly enough. The area with loose contact will have a greater impact on the heat dissipation, resulting in uneven overall temperature distribution of the substrate. At the same time, since the gas entering the cavity during the production process has a strong fluidity, when the airflow enters the gap at the bottom of the substrate, it is also easy to cause the problem of the substrate drifting on the horizontal plane, which should be avoided in the process of high-quality diamond growth. In order to solve the problems of uneven heat conduction and substrate drift, CN104185697B discusses the method of brazing a single crystal diamond substrate to a substrate holder and some suitable brazing alloys so as to obtain good adhesion and thermal contact between the substrate and the substrate holder, so as to improve the uniformity and yield of single crystal CVD synthetic diamond products. CN104972189B uses a vacuum brazing method to form a firm bond between a diamond sample and a metal molybdenum substrate, thereby preventing the problem of the seed crystal being blown away from the optimal position due to excessive airflow when evacuating and passing gas, and ensuring the stability of the growth process to a certain extent. However, a suitable welding medium needs to be used in the vacuum brazing method, and a special ratio of alloys is usually used, which not only needs to improve the compatibility with the diamond seed crystal, but also will not form a serious reaction interface layer, thus bringing difficulty to the implementation of the method. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a diamond growth molybdenum ring to solve the problem of uneven heat dissipation caused by the non-fitting contact of the diamond substrate surface in the prior art, and to cope with the problem of different sizes of diamond substrates making it difficult to select a molybdenum ring of appropriate size, as well as the problem of diamond substrate drift.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A diamond growth molybdenum ring comprises a molybdenum ring body, a through hole is formed on the molybdenum ring body, the through hole is used to connect diamond substrates of different sizes so that four side edges of the diamond substrate can contact the inner wall of the through hole, a supporting part is formed on the molybdenum ring body, the supporting part protrudes from the molybdenum ring body into the through hole, and the supporting part is used to support the diamond substrate.

[0008] The through hole is a centrally symmetrical shape formed by two identical ellipses orthogonally intersecting each other.

[0009] In the present invention, preferably, the ratio of the length of the major axis to the minor axis of the through hole meets the following formula:

[0010]

[0011] Where a is the length of the major axis of the ellipse, and b is the length of the minor axis of the ellipse.

[0012] In the present invention, preferably, the size of the molybdenum ring body and the through hole size conform to the following formula:

[0013] a+10mm≤Φ≤a+20mm,

[0014] Where Φ represents the diameter of the molybdenum ring body.

[0015] In the present invention, preferably, the supporting portion is specifically annular, and the shape of the supporting portion is adapted to the shape of the through hole.

[0016] In the present invention, preferably, the width of the protrusion of the supporting portion is set to 0.1 to 0.5 mm, and the height of the supporting portion is set to 0.5 to 1 mm.

[0017] Beneficial effects of the present invention:

[0018] 1. The present invention uses the through hole to make the side edge of the diamond substrate contact with the molybdenum ring body, and specifically shows line contact, so that the heat dissipation conditions of each side of the diamond substrate are similar, thereby improving the uniformity of heat dissipation of the diamond substrate in the side direction. The present invention uses the support part to make the diamond substrate detach from the contact with the water cooling table, thereby avoiding the problem of uneven heat dissipation caused by uneven contact area to the greatest extent, improving the uniformity of temperature distribution during the diamond growth process, thereby improving the uniformity of diamond growth, and the support part is provided so that the bottom of the diamond substrate has an open gap, so when the airflow enters the bottom of the diamond substrate, it is not easy to cause disturbance, thereby alleviating the problem of substrate drift on the horizontal plane;

[0019] 2. The shape of the through hole is set to be elliptical so that the variable size of the diamond substrate that can be placed is continuous rather than discrete, and it can accommodate diamond substrates of different sizes. It has strong versatility, making it easier for the substrate to fit a molybdenum ring of a suitable size. The diamond substrate is placed in the through hole and rotated clockwise or counterclockwise until the four side edges of the diamond substrate are against the inner wall of the through hole. After placement, the through hole limits the drift of the diamond substrate in the horizontal plane direction and limits the direction of the rotational drift of the diamond substrate, so that the possibility of drift of the diamond substrate is further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1Schematic diagram of the top view of the molybdenum ring body in this embodiment;

[0021] Figure 2 is a schematic diagram of the placement of diamond substrates of different sizes in this embodiment;

[0022] Figure 3 yes Figure 2 Schematic diagram of the actual perspective of the placement of the second substrate 402.

[0023] Reference numerals:

[0024] 10: Molybdenum ring body;

[0025] 20: Supporting part;

[0026] 30: through hole;

[0027] 401: a first substrate;

[0028] 402: a second substrate;

[0029] 403: The third substrate DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be a component centered. When a component is considered to be "connected to" another component, it may be directly connected to the other component or there may also be a component centered. When a component is considered to be "set on" another component, it may be directly set on the other component or there may also be a component centered. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0033] Please also see Figures 1 to 3The present embodiment provides a diamond growth molybdenum ring, including a molybdenum ring body 10, on which a through hole 30 is formed, and the through hole 30 is used to externally connect diamond substrates of different sizes so that the four side edges of the diamond substrate can contact the inner wall of the through hole 30. The present invention uses the through hole 30 to make the side edges of the diamond substrate contact with the molybdenum ring body 10, and specifically shows line contact, so that the heat dissipation conditions of each side of the diamond substrate are similar, thereby improving the uniformity of heat dissipation of the diamond substrate in the side direction.

[0034] In this embodiment, refer to Figure 1 and Figure 2 As shown, the through hole 30 is a centrally symmetrical shape formed by two identical ellipses orthogonally. The shape of the through hole 30 is set to an ellipse so that the variable size of the diamond substrate that can be placed is continuous rather than discrete, and diamond substrates of different sizes can be accommodated. And rotating the diamond substrate clockwise or counterclockwise can ultimately keep the four vertical edges of diamond substrates of different sizes in good contact with the inner edge of the through hole 30, thereby improving the uniformity of heat dissipation of the diamond substrate. The diamond substrate is placed in the through hole 30 and rotated clockwise or counterclockwise until the four side edges of the diamond substrate are against the inner wall of the through hole 30. After placement, the through hole 30 limits the drift of the diamond substrate in the horizontal plane direction, and limits the direction of the rotational drift of the diamond substrate, so that the possibility of drift of the diamond substrate is further reduced.

[0035] In this embodiment, refer to Figure 1 and Figure 2 As shown, the ratio of the length of the major axis to the minor axis of the through hole 30 conforms to the following formula:

[0036]

[0037] Where a is the length of the major axis of the ellipse, and b is the length of the minor axis of the ellipse.

[0038] The size of the molybdenum ring body 10 and the size of the through hole 30 conform to the following formula:

[0039] a+10mm≤Φ≤a+20mm,

[0040] Here, Φ represents the diameter of the molybdenum ring body 10. The size of the molybdenum ring body 10 is set to Φ multiplied by 1.5 mm.

[0041] And under the above constraints, the actual side length of the diamond substrate that can be placed meets the following formula:

[0042]

[0043] Where c represents the side length of the diamond substrate.

[0044] In this embodiment, see Figure 2 As shown, the first substrate 401 is the smallest substrate that can be placed on the molybdenum ring body 10, the third substrate 403 is the largest substrate that can be placed on the molybdenum ring body 10, and the size of the second substrate 402 is between the first substrate 401 and the third substrate 403. The elliptical shape setting makes the variable size of the diamond substrate that can be placed continuous rather than discrete, so that any value of the side length of the diamond substrate between 0.5a and the square root of two a can be used as the side length of the diamond substrate.

[0045] In this embodiment, see Figure 3 As shown, a supporting portion 20 is formed on the molybdenum ring body 10, and the supporting portion 20 protrudes from the molybdenum ring body 10 into the through hole 30. The supporting portion 20 is used to support the diamond substrate, so that the substrate and the water-cooling table are separated by a certain distance. The supporting portion 20 is specifically annular, and the shape of the supporting portion 20 is adapted to the shape of the through hole 30, so as to facilitate the support of diamond substrates of different sizes. The four corners of the diamond substrate are kept in contact with the supporting portion 20. The width of the protrusion of the supporting portion 20 is set to 0.1 to 0.5 mm, and the height of the supporting portion 20 is set to 0.5 to 1 mm. In order to reduce the contact area with the bottom of the diamond substrate, the protruding width of the supporting portion 20 is as small as possible, which is 0.1 to 0.5 mm. In order to avoid the influence of the water-cooling table on the local heat dissipation of the bottom surface of the substrate too fast, the height of the supporting portion 20 is 0.5 to 1 mm.

[0046] The above are only preferred embodiments of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A diamond growth molybdenum ring, characterized in that: The invention comprises a molybdenum ring body, wherein a through hole is formed on the molybdenum ring body, wherein the through hole is used to connect diamond substrates of different sizes so that four side edges of the diamond substrate can contact the inner wall of the through hole, and wherein a supporting portion is formed on the molybdenum ring body, wherein the supporting portion protrudes from the molybdenum ring body into the through hole, and wherein the supporting portion is used to support the diamond substrate. The through hole is a centrally symmetrical shape formed by two identical ellipses orthogonally intersecting each other.

2. The diamond growth molybdenum ring according to claim 1, characterized in that: The ratio of the length of the major axis to the minor axis of the through hole conforms to the following formula: Where a is the length of the major axis of the ellipse, and b is the length of the minor axis of the ellipse.

3. The diamond growth molybdenum ring according to claim 2, characterized in that: The size of the molybdenum ring body and the through hole size conform to the following formula: a+10mm≤Φ≤a+20mm, Where Φ represents the diameter of the molybdenum ring body.

4. The diamond growth molybdenum ring according to claim 1, characterized in that: The supporting portion is specifically annular, and the shape of the supporting portion is adapted to the shape of the through hole.

5. The diamond-grown molybdenum ring according to claim 4, characterized in that: The width of the protrusion of the supporting portion is set to 0.1 to 0.5 mm, and the height of the supporting portion is set to 0.5 to 1 mm.

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