An apparatus and method for creating a uniform temperature field for polycrystalline or single-crystal diamond growth.

Abstract

This invention provides an apparatus and method for creating a uniform temperature field for polycrystalline or single-crystal diamond growth, relating to the field of polycrystalline or single-crystal diamond crystals. The invention includes a growth holder, a substrate, and several heat dissipation adjustment plates that can be stacked sequentially. The substrate is placed on top of the growth holder and used for diamond deposition. The growth holder is placed on a heat dissipation platform containing cooling water channels. A heat dissipation groove is provided at the bottom of the growth holder, and a connecting post is provided within the groove. The heat dissipation adjustment plates have connecting through holes, and the connecting post is detachably connected to the connecting through hole. In this invention, heat dissipation adjustment plates of corresponding shape and number can be installed according to the shape and distribution of the temperature field in the diamond deposition region, so that the thermal conductivity of the inner, higher-temperature region in the diamond deposition region is higher, and the thermal conductivity of the outer, lower-temperature region in the diamond deposition region is lower, thus maintaining a balanced temperature field in the diamond deposition region.

Description

Technical Field

[0001] This invention relates to the field of polycrystalline or single-crystal diamond crystals, and in particular to an apparatus and method for creating a uniform temperature field for polycrystalline or single-crystal diamond growth. Background Technology

[0002] Diamond possesses an ultra-wide spectral transmittance range, excellent optical transmittance, ultra-high hardness and thermal conductivity, and an extremely low coefficient of thermal expansion. It also has low dielectric loss, which can meet the application requirements of window materials from X-ray and deep ultraviolet to microwave bands. It has become the first choice for optical devices under extreme conditions such as X-ray windows, infrared guidance windows, high-power CO2 laser windows, and high-energy microwave feed windows.

[0003] Currently, the most mature method for growing polycrystalline diamond wafers is microwave plasma chemical vapor deposition (MPCVD). However, in actual MPCVD diamond growth processes, due to variations in plasma shape and material ionization deposition rates, uneven temperature fields are often encountered in the diamond deposition region under changes in power, gas pressure, and gas flow rate. This results in inconsistent diamond growth environments in different regions, leading to uneven thickness, color differences between inner and outer rings, and reduced growth yield. Furthermore, for the growth of large-size polycrystalline or single-crystal diamonds, uneven thickness also increases the difficulty of subsequent processing, significantly reducing the finished product yield.

[0004] Currently, in the actual deposition and growth process of diamond, the temperature in the central region of the diamond growth temperature field is higher than that in the non-central region, and the high-temperature central region is generally asymmetrical and circular. For different machines and processes, the shape and size of the high-temperature central region in the diamond growth temperature field vary. However, the current devices used to establish a uniform diamond growth temperature field are all integrally molded, resulting in a narrow range of process adaptability adjustments. This directly leads to problems such as excessively high material costs, long processing cycles, and difficulties in processing specific irregularly shaped cooling zones.

[0005] Therefore, there is an urgent need for a device that can be flexibly adjusted to balance the growth temperature field. Summary of the Invention

[0006] To address the aforementioned problems, the first aspect of this invention provides an apparatus for creating a uniform temperature field for polycrystalline or single-crystal diamond growth, which can balance the temperature field in the diamond deposition region and significantly reduce costs.

[0007] The apparatus for uniform polycrystalline or single-crystal diamond growth temperature field provided by the present invention includes a growth holder, a substrate, and a plurality of heat dissipation adjustment plates that can be stacked sequentially. The substrate is disposed on top of the growth holder and is used for diamond deposition. The growth holder is used to place on a heat dissipation platform containing cooling water channels. The bottom of the growth holder is provided with a heat dissipation groove, and a connecting post is provided in the heat dissipation groove. The heat dissipation adjustment plates are provided with connecting through holes, and the connecting post is detachably connected to the connecting through hole. The plurality of heat dissipation adjustment plates can be stacked sequentially in the heat dissipation groove.

[0008] In one feasible embodiment, the center point of the heat dissipation groove is located on the central axis of the connecting column, and the central axis of the connecting column coincides with the central axis of the growth holder.

[0009] In one feasible embodiment, the shape of the heat dissipation adjustment plate is selected from any one of a cylinder, an elliptical cylinder, or a polygonal cylinder.

[0010] In one feasible embodiment, the heat dissipation adjustment plate is an elliptical cylinder with a major axis of 5-12 mm, a minor axis of 5-10 mm, and a thickness of 1-8 mm.

[0011] In one feasible embodiment, the growth support is cylindrical or elliptical; the heat dissipation groove is cylindrical or elliptical.

[0012] In one feasible embodiment, the growth support is cylindrical in shape, with a diameter of 110-140 mm and a height of 9-15 mm; the heat dissipation groove is cylindrical in shape, with a diameter of 70-100 mm and a depth of 1-8 mm.

[0013] In one feasible embodiment, the heat dissipation regulating plate is made of metal or alloy.

[0014] In one feasible embodiment, the growth substrate is made of metal or alloy.

[0015] In one feasible embodiment, the substrate material is selected from any one of silicon multi / single crystal, germanium multi / single crystal, silicon carbide multi / single crystal, gallium nitride multi / single crystal, aluminum nitride multi / single crystal, diamond multi / single crystal, or multiple combinations of the above materials, or a coating material.

[0016] A second aspect of the present invention provides a method for growing diamond, employing the apparatus for creating a uniform polycrystalline or single-crystal diamond growth temperature field as described in the first aspect of the present invention, comprising the following steps:

[0017] Step 1) Identify the high-temperature region on the substrate;

[0018] Step 2) Select several heat dissipation adjustment plates of appropriate specifications according to the shape of the high-temperature area;

[0019] Step 3) Install several heat dissipation adjustment plates sequentially into the heat dissipation groove;

[0020] Step 4) Place the growth tray into the growth chamber for growth.

[0021] In one feasible embodiment of the diamond growth method, step 1) further includes measuring the high-temperature region on the substrate by infrared radiation under process conditions of gas pressure of 10-15 kPa and growth power of 5-10 kW. The high-temperature region is elliptical in shape, with the major axis of the high-temperature region being 5-12 mm and the minor axis of the high-temperature region being 5-10 mm.

[0022] In one feasible embodiment of the diamond growth method, step 2) further includes selecting a number of heat dissipation adjustment plates with a major axis of 5-12 mm, a minor axis of 5-10 mm, and a thickness of 1-8 mm.

[0023] In one feasible embodiment of the diamond growth method, step 3) further includes threading the heat dissipation adjustment plate to the connecting post in the heat dissipation groove through the connecting through hole on each heat dissipation adjustment plate.

[0024] In one feasible embodiment of the diamond growth method, step 4) further includes evacuating the growth chamber to a vacuum level of 10. -2 Pa, then introduce growth gas into the growth chamber until the pressure reaches 10-15 kPa, and carry out heat preservation growth while maintaining a growth power of 5-10 kW.

[0025] The apparatus and method for creating a uniform polycrystalline or single-crystal diamond growth temperature field provided by this invention have the following features:

[0026] Beneficial effects:

[0027] 1. In this invention, heat dissipation adjustment plates of corresponding shape and number can be installed according to the shape and distribution of the temperature field in the diamond deposition area, so that the thermal conductivity of the inner circle temperature area in the diamond deposition area is higher and the thermal conductivity of the outer circle temperature area in the diamond deposition area is lower, so as to keep the temperature field in the diamond deposition area in balance.

[0028] 2. Furthermore, the heat dissipation adjustment plate in this invention can be processed separately, which greatly reduces the cost. The size and fit of the heat dissipation adjustment plate are adjustable. Irregular structures that cannot be completed by normal machining can be achieved through the heat dissipation adjustment plate. Attached Figure Description

[0029] Figure 1This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0030] Figure 2 Statistical thermal distribution map of temperature field in diamond deposition region

[0031] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention.

[0032] Figure Labels

[0033] Growth tray 1

[0034] Substrate 2

[0035] Heat dissipation adjustment plate 3

[0036] Connecting through hole 31

[0037] Heat dissipation groove 4

[0038] Connecting column 5

[0039] Heat sink 6 Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In the description of the present invention, it should be noted that the terms "left side", "right side", "upper side", "lower side", "above", "below", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0043] This invention provides an apparatus for creating a uniform temperature field for the growth of polycrystalline or single-crystal diamond. See Figure 1 or Figure 3 The system includes a growth tray 1, a substrate 2, and several heat dissipation adjustment plates 3 that can be stacked sequentially. The substrate 2 is located on top of the growth tray 1 and is used for diamond deposition. The growth tray 1 is placed on a heat dissipation platform 6 containing cooling water channels, which can cool the heat transferred from the diamond from top to bottom. The bottom of the growth tray 1 has a heat dissipation groove 4, and a connecting post 5 is provided in the heat dissipation groove 4. The heat dissipation adjustment plates 3 have connecting through holes, and the connecting post 5 is detachably connected to the connecting through hole. Typically, the connecting post 5 and the connecting through hole are threaded together. Current research indicates that the temperature field in the diamond deposition region is unbalanced, with the temperature in the central region significantly higher than that in the non-central region. Generally, grooves are dug along the edge of the growth tray 1 to even out the temperature in the diamond deposition region. However, the size and depth of these grooves need continuous adjustment based on different equipment and substrate 2. If the grooves are not large or deep enough, the temperature difference between the central and non-central regions of the diamond deposition region will be large. If the grooves are too large or deep, the overall temperature of the substrate 2 may rise, failing to meet the expected process conditions. This invention, however, uses a heat dissipation adjustment plate 3 to conveniently and quickly adjust the temperature field of the diamond deposition region. Specifically, the heat dissipation groove 4 in this invention first allows the diamond... A portion of the medium in the heat transfer path from the diamond deposition region to the heat dissipation platform 6 becomes gas. Subsequently, heat dissipation adjustment plates 3, matching the shape of the central region, are placed on the heat transfer path in the central region where the temperature is higher. This ensures that the medium in the heat transfer path of the central region is solid (heat transfer path of the central region: growth support 1 → several heat dissipation adjustment plates 3 → heat dissipation platform 6), while the medium in the heat transfer path of the non-central region is air (heat transfer path of the non-central region: growth support 1 → air → heat dissipation platform 6). Solids have a higher thermal conductivity than gases, so the heat dissipation in the central region is faster than in the non-central region, balancing the temperature field of the diamond deposition region and maintaining uniform temperature between different regions.

[0044] In one specific embodiment, see Figure 1 or Figure 3 The center point of the heat dissipation groove 4 is located on the central axis of the connecting column 5, and the central axis of the connecting column 5 coincides with the central axis of the growth support 1.

[0045] In one specific embodiment, the shape of the heat dissipation adjustment plate 3 is selected from any one of a cylinder, an elliptical cylinder, or a polygonal cylinder.

[0046] In one specific embodiment, the shape of the heat dissipation adjustment plate 3 is selected from any one of a cylinder, an elliptical cylinder, or a polygonal cylinder.

[0047] In one specific embodiment, the heat dissipation adjustment plate 3 is an elliptical cylinder with a major axis of 5-12 mm, a minor axis of 5-10 mm, and a thickness of 1-8 mm.

[0048] In one specific embodiment, the growth support 1 is cylindrical or elliptical; the heat dissipation groove 4 is cylindrical or elliptical.

[0049] In one specific embodiment, the growth support 1 is cylindrical in shape, with a diameter of 110-140 mm and a height of 9-15 mm; the heat dissipation groove 4 is cylindrical in shape, with a diameter of 70-100 mm and a depth of 1-8 mm.

[0050] In one specific embodiment, the heat dissipation regulating plate 3 is made of metal or alloy. Specifically, the heat dissipation regulating plate 3 is made of an alloy composed of one or more of the following metal materials: molybdenum, titanium, zirconium, tungsten, copper, iron, niobium, and tantalum.

[0051] In one specific embodiment, the growth substrate 1 is made of a metal or alloy. Specifically, the growth substrate 1 is made of an alloy composed of one or more of the following metals: molybdenum, titanium, zirconium, tungsten, copper, iron, niobium, and tantalum.

[0052] In one specific embodiment, the material of the substrate 2 is selected from any one of silicon multi / single crystal, germanium multi / single crystal, silicon carbide multi / single crystal, gallium nitride multi / single crystal, aluminum nitride multi / single crystal, diamond multi / single crystal, or multiple combinations of the above materials, or a coating material.

[0053] The present invention also provides a diamond growth method, which employs the apparatus described above for a uniform polycrystalline or single-crystal diamond growth temperature field, and includes the following steps:

[0054] Step 1) Identify the high-temperature region on substrate 2.

[0055] Furthermore, step 1) also includes measuring the high-temperature region on the substrate 2 by infrared radiation under process conditions of gas pressure of 10-15 kPa and growth power of 5-10 kW. The high-temperature region is elliptical in shape, with the major axis of the high-temperature region being 5-12 mm and the minor axis of the high-temperature region being 5-10 mm.

[0056] Step 2) Select several heat dissipation adjustment plates of appropriate specifications according to the shape of the high temperature area.

[0057] Furthermore, step 2) also includes selecting several heat dissipation adjustment plates 3 with a major axis of 5-12mm, a minor axis of 5-10mm, and a thickness of 1-8mm.

[0058] Step 3) Install several heat dissipation adjustment plates 3 into the heat dissipation groove 4 in sequence.

[0059] Furthermore, step 3) also includes threading the heat dissipation adjustment plate 3 to the connecting post 5 in the heat dissipation groove 4 through the connecting through hole on each heat dissipation adjustment plate 3.

[0060] Step 4) Place growth tray 1 into the growth chamber for growth.

[0061] Furthermore, step 4) also includes evacuating the growth chamber to a vacuum level of 10. -2 Pa, then introduce growth gas into the growth chamber to a pressure of 10-15 kPa, with a growth power of 5-10 kW.

[0062] Example 1

[0063] In this embodiment, a 2-inch substrate 2 is used for deposition. The growth tray 1 can be a general-purpose growth tray 1 with a diameter of 130 mm and a height of 14 mm. The heat dissipation groove 4 has a diameter of 80 mm and a depth of 7 mm.

[0064] Step 1) Identify the high-temperature region on substrate 2.

[0065] Furthermore, under conditions of 14 kPa pressure and 6 kW growth power, elliptical high-temperature regions with a major axis of 10 mm and a minor axis of 8 mm were obtained by infrared measurement of different regions of substrate 2, such as... Figure 2 As shown.

[0066] Step 2) Select several heat dissipation adjustment plates of appropriate specifications according to the shape of the high temperature area.

[0067] Furthermore, an elliptical heat dissipation adjustment plate 3 with a major axis of 10mm, a minor axis of 8mm, and a thickness of 7mm is selected.

[0068] Step 3) Install several heat dissipation adjustment plates 3 sequentially into the heat dissipation groove 4;

[0069] Furthermore, align the connecting through hole in the heat dissipation adjustment plate 3 with the connecting post 5, and then connect the heat dissipation adjustment plate 3 and the connecting post 5 by means of threads.

[0070] Step 4) Place growth tray 1 into the growth chamber for growth.

[0071] Furthermore, the growth chamber was evacuated to a vacuum level of 10. -2 Pa, then growth gas was introduced into the growth chamber until the pressure reached 14 kPa, and growth was carried out under heat preservation while maintaining a growth power of 6 kW. Comparative data are shown in Table 1 below:

[0072] surface 1

[0073]

[0074]

[0075] Data shows that after adjusting the temperature field of the diamond growth region using this embodiment, the thickness difference of diamond deposition at each location is only 0.07 mm, and the thickness non-uniformity is only 8.6%, which is nearly 40% higher than the mode without adjustment using this embodiment.

[0076] Example 2

[0077] In this embodiment, a 3-inch substrate 2 is used for deposition. The growth tray 1 can be a general-purpose growth tray 1 with a diameter of 130 mm and a height of 14 mm. The heat dissipation groove 4 has a diameter of 80 mm and a depth of 6 mm.

[0078] Step 1) Identify the high-temperature region on substrate 2.

[0079] Furthermore, under the conditions of gas pressure of 13 kPa and growth power of 7 kW, an elliptical high-temperature region with a major axis of 8 mm and a minor axis of 6 mm and a circular high-temperature region with a diameter of 15 mm were obtained by infrared measurement of different regions of substrate 2. The center points of these two high-temperature regions coincide.

[0080] Step 2) Select several heat dissipation adjustment plates of appropriate specifications according to the shape of the high temperature area.

[0081] Furthermore, an elliptical heat dissipation adjustment plate 3 with a major axis of 8mm, a minor axis of 6mm, and a thickness of 3mm and a circular heat dissipation adjustment plate 3 with a diameter of 15mm and a thickness of 3mm are selected.

[0082] Step 3) Install several heat dissipation adjustment plates 3 sequentially into the heat dissipation groove 4;

[0083] Furthermore, first align the connecting through hole in the elliptical heat dissipation adjustment plate 3 with the connecting post 5, and then connect the elliptical heat dissipation adjustment plate 3 to the connecting post 5 using threads; then align the connecting through hole in the circular heat dissipation adjustment plate 3 with the connecting post 5, and then connect the circular heat dissipation adjustment plate 3 to the connecting post 5 using threads.

[0084] Step 4) Place growth tray 1 into the growth chamber for growth.

[0085] Furthermore, the growth chamber was evacuated to a vacuum level of 10. -2 Pa, then introduce growth gas into the growth chamber until the pressure reaches 13 kPa, and carry out heat preservation growth while maintaining a growth power of 6 kW.

[0086] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. An apparatus for creating a uniform temperature field for polycrystalline or single-crystal diamond growth, characterized in that: It includes a growth tray (1), a substrate (2) and several heat dissipation adjustment plates (3) that can be stacked in sequence. The substrate (2) is located on top of the growth tray (1) and is used for diamond deposition. The growth tray (1) is placed on a heat dissipation platform containing cooling water channels. The bottom of the growth tray (1) is provided with a heat dissipation groove (4), and a connecting post (5) is provided in the heat dissipation groove (4). The heat dissipation adjustment plate (3) is provided with a connecting through hole, and the connecting post (5) is detachably connected to the connecting through hole. Several heat dissipation adjustment plates (3) can be stacked in the heat dissipation groove (4) in sequence. The center point of the heat dissipation groove (4) is located on the central axis of the connecting post (5), and the central axis of the connecting post (5) coincides with the central axis of the growth support (1).

2. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 1, characterized in that: The shape of the heat dissipation adjustment plate (3) is selected from any one of a cylinder, an elliptical cylinder or a polygonal cylinder.

3. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 2, characterized in that: The heat dissipation adjustment plate (3) is an elliptical cylinder with a major axis of 5~12mm, a minor axis of 5~10mm, and a thickness of 1~8mm.

4. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 1, characterized in that: The growth support (1) is cylindrical or elliptical; the heat dissipation groove (4) is cylindrical or elliptical.

5. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 4, characterized in that: The growth support (1) is cylindrical in shape, with a diameter of 110-140 mm and a height of 9-15 mm; the heat dissipation groove (4) is cylindrical in shape, with a diameter of 70-100 mm and a depth of 1-8 mm.

6. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 1, characterized in that: The heat dissipation regulating plate (3) is made of metal or alloy; and / or the growth tray (1) is made of metal or alloy.

7. The apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field according to claim 1, characterized in that: The substrate (2) is made of any one of silicon multi / single crystal, germanium multi / single crystal, silicon carbide multi / single crystal, gallium nitride multi / single crystal, aluminum nitride multi / single crystal, diamond multi / single crystal, or a combination of the above materials, or a coating material.

8. A method for growing diamond, employing the apparatus for a uniform polycrystalline or single-crystal diamond growth temperature field as described in any one of claims 1 to 7, comprising the following steps: Step 1) Identify the high-temperature region on the substrate (2); Step 2) Select several heat dissipation adjustment plates of appropriate specifications according to the shape of the high temperature area (3); Step 3) Install several heat dissipation adjustment plates (3) into the heat dissipation groove (4) in sequence; Step 4) Place the growth tray (1) into the growth chamber for growth.

9. The diamond growth method according to claim 8, characterized in that, Includes any of the following technical features: Step 1) also includes, under the process conditions of gas pressure 10~15kPa and growth power 5~10kW, the high temperature region on the substrate (2) is measured by infrared light. The high temperature region is elliptical in shape, with the major axis of the high temperature region being 5~12mm and the minor axis of the high temperature region being 5~10mm. Step 2) also includes selecting several heat dissipation adjustment plates (3) with a long axis of 5~12mm, a short axis of 5~10mm, and a thickness of 1~8mm. Step 3) also includes threading the heat dissipation adjustment plate (3) to the connecting post (5) in the heat dissipation groove (4) through the connecting through hole on each heat dissipation adjustment plate (3); Step 4) also includes evacuating the growth chamber to a vacuum level of 10. -2 Pa, then introduce growth gas into the growth chamber until the pressure reaches 10~15kPa, and carry out heat preservation growth while maintaining a growth power of 5~10kW.

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