Preparation method of large-thickness (111) crystal orientation monocrystal diamond for semiconductor

Abstract

The invention discloses a preparation method of a large-thickness (111) crystal orientation monocrystal diamond for a semiconductor, and aims to solve the problems of low growth rate and poor growth quality of the (111) crystal orientation diamond. The preparation method of the monocrystal diamond comprises the following steps: S1, heating and soaking a seed wafer in mixed acid; s2, performing etching treatment on the seed wafer by using hydrogen plasma; s3, oxygen is introduced into the vacuum cavity; s4, methane continues to be introduced into the vacuum cavity, the volume concentration of methane, hydrogen and oxygen is controlled, and microwave plasma chemical vapor deposition growth is carried out; s5, controlling the growth time; and S6, polycrystals on the surface of the blank are cut off. According to the method, the MPCVD process is adopted, and parameters such as gas concentration, temperature, pressure intensity and microwave energy in the growth process are controlled, so that homoepitaxial growth of the high-quality single crystal (111) crystal orientation diamond is realized, the production cost of the (111) crystal orientation diamond is reduced, and the realization of mass production of the (111) crystal orientation single crystal diamond is facilitated.

Description

Technical Field

[0001] This invention belongs to the field of diamond growth, and specifically relates to a method for preparing thick (111) crystal orientation single crystal diamond for use in semiconductors. Background Technology

[0002] Diamond, with its stable physicochemical properties, high thermal conductivity, wide bandgap, high insulation, and good biocompatibility, has become one of the most promising functional materials in recent years, and is expected to become a "fourth-generation" semiconductor material, with broad application prospects in precision machining, high-frequency communication, aerospace, and other fields. Initially, the scarcity and high price of natural diamond limited its industrial applications. However, with continuous technological advancements and the needs of various fields, synthetic diamonds, with their similar structure to natural diamonds, fewer defects, superior performance, lower cost, and higher production volume, have gained widespread application advantages and market prospects.

[0003] Currently, the main methods for synthesizing diamond are HPHT (High Pressure High Temperature) and CVD (Chemical Vapor Deposition). Compared to HPHT, CVD is widely used in diamond production due to its advantages such as faster crystal growth rate, higher crystal yield, and higher crystal quality.

[0004] Currently, synthesized diamonds are mainly in the (100) crystal orientation because the (100) crystal orientation has a high growth rate, low requirements for the growth environment, and is easier to grow, making it more suitable for applications in optics, gemstones, and other fields. However, in the process of preparing semiconductor devices, the poor element doping effect of the (100) crystal orientation limits the application of diamond materials in the semiconductor field. In contrast, the higher covalent bond density of the (111) crystal orientation makes the chemical activity of the crystal face relatively high, making it easier to interact with dopant atoms and promote the adsorption and bonding of dopant atoms. In addition, in quantum measurement applications based on diamond NV centers, in the NV center layer prepared with (100) as the substrate, the NV center axes are respectively along

[111] and [1]. ]、[ 1]、[ Uniformly distributed. During signal collection, due to axial differences, only 1 / 4 of the NV color centers provide effective signals ( a and c), the remaining NV centers increase background noise, leading to data anomalies. In the NV center layer homoepitaxially grown on the (111) substrate using MPCVD, the orientation rate of the NV center crystal axis along the

[111] direction can reach more than 80%. (b and d) significantly improve the signal-to-noise ratio of the measurement. It can be seen that (111) crystal-oriented diamond materials have great application prospects in fields such as semiconductors and quantum measurement.

[0005] (111) Oriented single-crystal diamond can be prepared by two methods: directional cutting or direct growth. Directional cutting refers to using a bulk MPCVD or HPHT diamond preform as a substrate and then using a laser to directionally cut the substrate, such as... As shown, this method is currently the main method for preparing (111) single crystal wafers. However, this method has many drawbacks: 1) Due to the limitation of substrate size, it is impossible to prepare large-thickness (111) bulk diamond crystals; 2) Laser cutting and subsequent polishing will cause subsurface damage to the (111) surface, affecting the performance of electrical devices based on diamond processing and the performance of NV color centers; 3) Since this method is based on (100) diamond substrate to prepare (111) bulk diamond, due to the poor doping effect of (100), it is impossible to directly prepare (111) bulk diamond with high element doping concentration; 4) In terms of material and processing costs, this method is expensive, difficult to operate, and difficult to achieve mass production.

[0006] Direct growth is a method of growing (111) oriented bulk diamond directly through homo- or hetero-epitaxial growth using MPCVD. Compared to directional cutting, this method is simpler to operate and can obtain high-quality (111) diamonds of different sizes by controlling the growth parameters. Furthermore, in-situ doping can be performed directly during the growth process to obtain (111) diamonds with higher elemental doping concentrations. Epitaxial growth of diamond has been studied by scholars since the last century. (100) diamond growth technology, whether homo- or hetero-epitaxial, has become mature. The research and application of bias nucleation technology and Ir substrates have made the generation of large-size diamond wafers possible. However, due to the influence of atomic arrangement, the growth of (111) crystal orientation is much more difficult than that of (100). For example, the quality of (111) crystal is related to the growth rate. If the growth is too fast, it is easy to grow quasi-single crystals or polycrystalline crystals, which will affect the performance of the device. The growth environment of (111) crystal is more demanding. Too high a methane concentration or too low a growth temperature will result in the growth of a graphite layer on the surface. The quality requirements of the substrate for (111) crystal growth are higher. Too large a crystal plane deflection angle or severe crystal plane damage will lead to the failure of single crystal epitaxial growth. It can be seen that the growth process of (111) cannot be applied to the growth process of (100). Further exploration of the growth process is needed to grow high-quality (111) diamond single crystals. Summary of the Invention

[0007] The purpose of this invention is to address the problem that (111) crystal orientation diamond has application prospects in semiconductors, quantum measurement and other fields, but has a low growth rate and poor growth quality, and to provide a method for preparing thick (111) crystal orientation single crystal diamond for semiconductors.

[0008] The method for preparing thick (111) crystal orientation single-crystal diamond for semiconductors according to the present invention is implemented according to the following steps:

[0009] Step S1: The (111) seed crystal is placed in a mixed acid for heating and soaking, and then washed to obtain a pretreated seed crystal;

[0010] Step S2: In the vacuum chamber of the MPCVD device, the pretreated seed crystal is placed on the molybdenum support, the vacuum chamber is evacuated, and then hydrogen gas is introduced to perform etching using hydrogen plasma.

[0011] Step S3: Introduce oxygen into the vacuum chamber;

[0012] Step S4: Continue to introduce methane into the vacuum chamber, controlling the volume concentration of methane to be 0.3-4%, the volume concentration of hydrogen to be 99.7-96%, and the volume concentration of oxygen to be 1%-10%. Control the growth temperature to be 1000-1500℃, the microwave energy range to be 4-6KW, and the pressure to be 10-20kPa for microwave plasma chemical vapor deposition growth.

[0013] Step S5: Control the growth thickness of the diamond by controlling the growth time (111). After the growth is completed, gradually reduce the pressure and temperature in the vacuum chamber to obtain the diamond blank.

[0014] Step S6: Use a laser cutter to remove the polycrystalline material on the surface of the diamond blank to obtain a thick (111) crystal orientation single crystal diamond.

[0015] This invention proposes a method for preparing thick (111) oriented single-crystal diamond for semiconductor applications. It innovatively proposes using oxygen as an auxiliary gas to improve the growth quality of (111) oriented single-crystal diamond while controlling the crystal growth rate and suppressing polycrystalline growth. During the growth process, a low-methane, high-temperature growth environment is used to promote (111) oriented growth and suppress (100) oriented growth. Furthermore, different thicknesses can be achieved by controlling the growth time, and various elemental doping can be realized by controlling the gas source composition.

[0016] This invention utilizes MPCVD to homoepitaxially grow (111) oriented single-crystal diamond. This innovative method incorporates oxygen, reduces the proportion of methane, and increases the growth temperature during the growth process, resulting in high-quality (111) oriented single-crystal diamond with controllable thickness. This reduces the production cost of (111) diamond and allows for various doping effects through solid-state or gaseous doping during (111) crystal growth, providing a sound material foundation for the fabrication of diamond semiconductor devices. Attached Figure Description

[0017] Figure 1 (a) ODMR test fitting curve of NV color center in crystal direction (111); (b) Schematic diagram of NV color center axis in diamond parallel to

[111] direction in (111); (c) ODMR test fitting curve of NV color center in crystal direction (100); (d) Random distribution diagram of NV color center direction in diamond in (100);

[0018] Figure 2. Schematic diagram of diamond crystal facet directional cutting;

[0019] Figure 3 shows the effect of the optimization of the growth environment on the growth quality of (111) diamond in this invention. (a) is a quasi-single crystal grown on the surface of the seed crystal without the addition of oxygen; (b) is a graphite layer grown on the surface of the crystal at low temperature and high methane content; (c) is a (111) single crystal diamond grown by homoepitaxial growth at high temperature and low methane content after the addition of oxygen.

[0020] Figure 4 is a growth flow diagram of the method for preparing thick (111) crystal orientation single crystal diamond for semiconductors according to the present invention;

[0021] Figure 5 is a schematic diagram of (111) crystal orientation seed crystal etching and growth in this invention;

[0022] Figure 6 shows the surface morphology of the (111) homoepitaxial single crystal diamond grown in the embodiment.

[0023] Figure 7 shows the Raman data of the (111) homoepitaxial single-crystal diamond grown in the embodiment;

[0024] Figure 8 shows the XRD pattern of the (111) homoepitaxial single crystal diamond grown in the example. Detailed Implementation

[0025] Specific Implementation Method 1: The preparation method of thick (111) crystal orientation single crystal diamond for semiconductors in this implementation method is carried out according to the following steps:

[0026] Step S1: The (111) seed crystal is placed in a mixed acid for heating and soaking, and then washed to obtain a pretreated seed crystal;

[0027] Step S2: In the vacuum chamber of the MPCVD device, the pretreated seed crystal is placed on the molybdenum support, the vacuum chamber is evacuated, and then hydrogen gas is introduced to perform etching using hydrogen plasma.

[0028] Step S3: Introduce oxygen into the vacuum chamber;

[0029] Step S4: Continue to introduce methane into the vacuum chamber, controlling the volume concentration of methane to be 0.3-4%, the volume concentration of hydrogen to be 99.7-96%, and the volume concentration of oxygen to be 1%-10%. Control the growth temperature to be 1000-1500℃, the microwave energy range to be 4-6KW, and the pressure to be 10-20kPa for microwave plasma chemical vapor deposition growth.

[0030] Step S5: Control the growth thickness of the diamond by controlling the growth time (111). After the growth is completed, gradually reduce the pressure and temperature in the vacuum chamber to obtain the diamond blank.

[0031] Step S6: Use a laser cutter to remove the polycrystalline material on the surface of the diamond blank to obtain a thick (111) crystal orientation single crystal diamond.

[0032] In this embodiment, the introduction of oxygen in step S3 is crucial for growing high-quality (111) single-crystal diamond. By controlling the oxygen volume concentration, different requirements for (111) single-crystal diamond can be met. High oxygen concentration results in a relatively slow diamond growth rate but high crystal quality, while low oxygen concentration accelerates the diamond growth rate but reduces crystal quality. In step S4, growth temperatures below 1000℃ or above 1500℃ will cause graphite formation on the crystal surface; therefore, the temperature must be strictly controlled between 1000 and 1500℃. In step S5, because the (111) crystal orientation is prone to internal stress during polishing, slow cooling is required to prevent crystal breakage. In step S6, if the growth is long and the seed crystals are densely packed, laser segmentation is necessary; if the gaps between crystals are large and the growth time is short, this operation is not required.

[0033] In step S2 of this embodiment, the seed crystal is placed on the molybdenum support in the MPCVD cavity. Different sizes and quantities of blanks can be placed according to the size of the molybdenum support and production needs. After placement, the cavity needs to be evacuated and then hydrogen gas is introduced to increase the temperature, pressure and microwave energy inside the cavity.

[0034] Specific Implementation Method Two: The difference between this implementation method and Specific Implementation Method One is that in step S1 (111), the seed crystal is HPHT or CVD single crystal diamond.

[0035] In this embodiment, the diamond blank is a high-quality HPHT or CVD single crystal diamond with no internal impurities under a 50x microscope. A (111) seed crystal is directionally cut using a laser cutter with a crystal face deflection angle of less than 5°. The seed crystal prepared by HPHT has lower internal stress and higher quality crystal after growth.

[0036] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that the seed wafer in step S1 (111) is pre-treated by mechanical or chemical mechanical polishing (Ra is at the nanometer level).

[0037] Specific Implementation Method Four: This implementation method differs from one of the specific implementation methods one to three in that in step S1, the (111) seed crystal is placed in mixed acid and heated to 250~300℃ for 2~3 hours.

[0038] Specific Implementation Method Five: This implementation method differs from Specific Implementation Method Four in that the mixed acid is composed of concentrated sulfuric acid with a mass concentration of 98% and concentrated nitric acid with a mass concentration of 67% in a volume ratio of 3:1.

[0039] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that in step S2, the pre-treated seed crystal and the solid source are placed on the molybdenum support, and the solid source is boron nitride or single crystal silicon.

[0040] This implementation method allows for the selection of a suitable solid-state source based on specific doping requirements.

[0041] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the temperature range is controlled at 600~800℃, the pressure at 7~10kPa, and the microwave energy range at 2~4kW during the etching process in step S2, and the crystal etching time is 30~60min.

[0042] Specific Implementation Method Eight: This implementation method differs from Specific Implementation Methods One to Seven in that oxygen is introduced into the vacuum chamber in step S3, and the volume concentration of oxygen is controlled to be 1% to 2%.

[0043] Specific Implementation Method Nine: This implementation method differs from Specific Implementation Method Eight in that, in step S4, the volume concentration of methane is controlled at 0.8%~2%, the volume concentration of hydrogen at 99%~97%, the volume concentration of oxygen at 1%~1.5%, the growth temperature is controlled at 1000~1200℃, the microwave energy range is 4~6kW, and the pressure is 16~18kPa for microwave plasma chemical vapor deposition growth.

[0044] Specific Implementation Method 10: This implementation method differs from Specific Implementation Methods 1 to 9 in that, in step S4, methane and borane are continued to be introduced into the vacuum chamber, and the volume ratio of methane to borane is controlled to be (0.8~1.2):(0.4~0.6).

[0045] Specific Implementation Method Eleven: This implementation method differs from Specific Implementation Methods One to Ten in that the thickness of the large-thickness (111) crystal orientation single crystal diamond obtained in step S6 is 500µm~2000µm.

[0046] Example 1: The preparation method of thick (111) crystal orientation single crystal diamond for semiconductors in this example is implemented according to the following steps:

[0047] Step S1: Select HPHT single crystals with smooth surfaces and no obvious impurities under a 50x microscope as seed crystals. Use a laser cutter to cut the (111) crystal facet seed crystals with a crystal orientation angle of less than 1°. Then, mechanically polish the seed crystals to a roughness of less than 5nm. Place the (111) seed crystals in a mixed acid solution and heat to 260°C for 2 hours. Then, ultrasonically wash with alcohol for 30 minutes and ultrasonically wash with pure water for 30 minutes to obtain pretreated seed crystals. The mixed acid solution is a mixture of concentrated sulfuric acid with a mass concentration of 98% and concentrated nitric acid with a mass concentration of 67% in a volume ratio of 3:1.

[0048] Step S2: In the vacuum chamber of the MPCVD device, the pretreated seed crystal is placed on the molybdenum support, the vacuum chamber is evacuated, and then hydrogen and oxygen are introduced. When the temperature reaches 750℃, the microwave energy is 3kW, and the pressure is 10kPa, the flow ratio of hydrogen and oxygen is 190:10, and plasma etching begins. The etching time is 60min.

[0049] Step S3: Introduce oxygen into the vacuum chamber;

[0050] Step S4: Continue to introduce methane into the vacuum chamber, controlling the volume concentration of methane to 1%, the volume concentration of hydrogen to 98%, the volume concentration of oxygen to 1%, and controlling the growth temperature to 1000℃, the microwave energy to 5kW, and the pressure to 18kPa for microwave plasma chemical vapor deposition growth.

[0051] Step S5: Control the growth thickness of (111) diamond by controlling the growth time. After the growth is completed, gradually reduce the pressure and temperature in the vacuum chamber to obtain a diamond blank. The (111) crystal orientation single crystal diamond blank of 3mm×3mm is grown for 100h. After the growth time is reached, slowly reduce the microwave source energy, cavity pressure and cavity temperature. When the cavity temperature reaches room temperature, turn off the microwave source and equipment vacuum pump, fill the cavity with air, so that the cavity pressure is close to atmospheric pressure, open the chamber cover and take out the sample.

[0052] Step S6: Use a laser cutter to remove the polycrystalline material on the surface of the diamond blank to obtain a (111) crystal single crystal diamond with a thickness of 400µm.

[0053] In this embodiment, the introduction of oxygen in S3 is the key to growing high-quality (111) single crystal diamond. By controlling the oxygen volume concentration, different requirements for (111) single crystal diamond can be achieved. With a high oxygen concentration, the diamond growth rate is relatively slow, but the crystal quality is high. With a low oxygen concentration, the diamond growth rate is faster, but the crystal quality is reduced.

[0054] The crystal surface of the example exhibits a stepped morphology (see Figure 6), and the intrinsic peak at 1332 cm⁻¹ was obtained by Raman spectroscopy. -1 The half-width at half maximum (FWHM) can reach 2.5 (see Figure 7), indicating that the crystal quality is high. In addition, the X-ray rocking curve test (see Figure 8) shows that 2θ is 43.9° and no crystal plane diffraction peak shift is observed, indicating that the grown crystal is a high-quality (111) crystal orientation single crystal diamond.

[0055] Example 2: The preparation method of thick (111) crystal orientation single crystal diamond for semiconductors in this example is implemented according to the following steps:

[0056] Step S1: Select HPHT single crystals with smooth surfaces and no obvious impurities under a 50x microscope as seed crystals. Use a laser cutter to cut the (111) crystal facet seed crystals with a crystal orientation angle of less than 1°. Then, mechanically polish the seed crystals to a roughness of less than 5nm. Place the (111) seed crystals in a mixed acid solution and heat to 260°C for 2 hours. Then, ultrasonically wash with alcohol for 30 minutes and ultrasonically wash with pure water for 30 minutes to obtain pretreated seed crystals. The mixed acid solution is a mixture of concentrated sulfuric acid with a mass concentration of 98% and concentrated nitric acid with a mass concentration of 67% in a volume ratio of 3:1.

[0057] Step S2: In the vacuum chamber of the MPCVD device, the pretreated seed crystal is placed on the molybdenum support, the vacuum chamber is evacuated, and then hydrogen and oxygen are introduced. When the temperature reaches 750℃, the microwave energy is 3kW, and the pressure is 10kPa, the flow ratio of hydrogen and oxygen is 190:10, and plasma etching begins. The etching time is 60min.

[0058] Step S3: Introduce oxygen (O2 purity greater than 99.99%) into the vacuum chamber;

[0059] Step S4: Continue to introduce methane and borane into the vacuum chamber, controlling the volume concentration of methane (methane purity greater than 99.99%) to be 1%, the volume concentration of hydrogen to be 97.5%, the volume concentration of borane to be 0.5%, and the volume concentration of oxygen to be 1%. Control the growth temperature to be 1000℃, the microwave energy to be 5kW, and the pressure to be 18kPa for microwave plasma chemical vapor deposition growth.

[0060] Step S5: Control the growth thickness of (111) diamond by controlling the growth time. After the growth is completed, gradually reduce the pressure and temperature in the vacuum chamber to obtain a diamond blank. The (111) crystal orientation single crystal diamond blank of 3mm×3mm is grown for 5h. After the growth time is reached, slowly reduce the microwave source energy, cavity pressure and cavity temperature. When the cavity temperature reaches room temperature, turn off the microwave source and equipment vacuum pump, fill the cavity with air, so that the cavity pressure is close to atmospheric pressure, open the chamber cover and take out the sample.

[0061] Step S6: Use a laser cutter to remove the polycrystalline material on the surface of the diamond blank to obtain a boron-doped (111) crystal single crystal diamond with a thickness of 60 micrometers.

[0062] The crystals grown in Example 2 are mainly used to meet the demand for highly doped diamond materials in fields such as semiconductors. This method allows for flexible control of doping elements and doped layer thickness.

[0063] This invention presents a method for homoepitaxial growth of (111) oriented single-crystal diamond using MPCVD. This method enables the mass production of (111) oriented single-crystal diamonds of various sizes. On the one hand, it reduces production costs by enabling large-scale production of (111) oriented single-crystal diamonds; on the other hand, it allows for the control of elemental doping during the growth process by controlling the composition of the plasma, thus achieving the preparation of semiconductor materials. This lays the material foundation for the application of diamond materials in the semiconductor field and has high market application value and prospects.

[0064] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing thick (111) crystal-oriented single-crystal diamond for semiconductors, characterized in that... The method for preparing thick (111) crystal-oriented single-crystal diamond for semiconductors is implemented according to the following steps: Step S1: The (111) seed crystal is placed in a mixed acid for heating and soaking, and then washed to obtain a pretreated seed crystal; Step S2: In the vacuum chamber of the MPCVD device, the pretreated seed crystal is placed on the molybdenum support, the vacuum chamber is evacuated, and then hydrogen gas is introduced to perform etching using hydrogen plasma. Step S3: Introduce oxygen into the vacuum chamber; Step S4: Continue to introduce methane into the vacuum chamber, controlling the volume concentration of methane to be 0.3%~4%, the volume concentration of hydrogen to be 99.7%~96%, the volume concentration of oxygen to be 1%~10%, controlling the growth temperature to be 1000~1500℃, the microwave energy range to be 4~6KW, and the pressure to be 10~20kPa for microwave plasma chemical vapor deposition growth. Step S5: Control the growth thickness of the diamond by controlling the growth time (111). After the growth is completed, gradually reduce the pressure and temperature in the vacuum chamber to obtain the diamond blank. Step S6: Use a laser cutter to remove the polycrystalline material on the surface of the diamond blank to obtain a thick (111) crystal orientation single crystal diamond.

2. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S1 (111), the seed crystal is HPHT or CVD single crystal diamond.

3. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S1 (111), the seed wafer is pre-polished mechanically or chemically.

4. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S1, the (111) seed crystal is placed in mixed acid and heated to 250~300℃ for 2~3 hours.

5. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 4, characterized in that... The mixed acid is composed of concentrated sulfuric acid with a mass concentration of 98% and concentrated nitric acid with a mass concentration of 67% in a volume ratio of 3:

1.

6. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S2, the pretreated seed crystal and the solid source are placed on the molybdenum support, wherein the solid source is boron nitride or single crystal silicon.

7. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S3, oxygen is introduced into the vacuum chamber, and the volume concentration of oxygen is controlled to be 1%~2%.

8. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S4, the volume concentration of methane is controlled at 0.8%~2%, the volume concentration of hydrogen is 99%~97%, the volume concentration of oxygen is 1%~1.5%, the growth temperature is controlled at 1000~1200℃, the microwave energy range is 4~6kW, and the pressure is 16~18kPa for microwave plasma chemical vapor deposition growth.

9. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... In step S4, methane and borane are continued to be introduced into the vacuum chamber, and the volume ratio of methane to borane is controlled to be (0.8~1.2):(0.4~0.6).

10. The method for preparing thick (111) oriented single-crystal diamond for semiconductors according to claim 1, characterized in that... The thickness of the (111) crystal orientation single crystal diamond obtained in step S6 is 500µm~2000µm.

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