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The excellent physicochemical properties of diamond make it widely used in many fields. Diamond is an indirect bandgap semiconductor material with a forbidden bandwidth of about 5.2eV, thermal conductivity as high as 22W/(cmK), and room temperature electron and hole mobility as high as 4500cm2/(V.s) and 3380cm2/(V.s), which is much higher than that of the third-generation semiconductor materials, GaN and SiC, so diamond has wide application prospects for the high-temperature operation of high-power power power electronics devices, high-frequency high-power microwave devices, and also has a great exciton binding energy (80meV), which makes it widely used in many fields. Therefore, diamond has a wide range of application prospects in high power power power electronic devices, high frequency and high power microwave devices. In addition, because diamond has a large exciton binding energy (80meV), so that it can realize high-intensity free exciton emission (light wavelength of about 235nm) at room temperature, which has a greater potential in the preparation of high power deep ultraviolet light-emitting diodes, and also plays an important role in the development of the extreme ultraviolet, deep ultraviolet, and high-energy particle detectors. Although there are still many difficulties in the growth of semiconductor diamond materials and the development of devices, it can be predicted that the application of semiconductor diamond materials and devices is very likely to bring about significant changes in science and technology in the near future.

The preparation methods of single crystal diamond mainly include high temperature and high pressure (HPHT) method and chemical vapor deposition (CVD) method. The monocrystalline diamond prepared by high temperature and high pressure method using metal catalyst will inevitably be doped with more metal impurities, which is difficult to meet the requirements of semiconductor devices on the material, and the CVD method mainly consists of the hot-wire CVD method, the DC jet CVD method, the DC discharge CVD method, the radio-frequency CVD method, and the microwave plasma CVD (MPCVD) method, among which the MPCVD method has many advantages, and it is recognized as the best method to prepare high-quality monocrystalline diamond. MPCVD has many advantages and is currently recognized as the best method for the preparation of high quality single crystal diamonds. the absence of internal electrodes in the MPCVD reaction chamber eliminates the problem of electrode contamination, as well as the continuous and smooth adjustment of the microwave power, the high conversion rate of the microwave energy, the high density of the plasma, and the stable conditions in the reaction chamber are the features that make the MPCVD uniquely advantageous in the preparation of high-quality semiconductor diamonds. Semiconductor devices have high demands on the quality of materials, and the introduction of defects can cause serious effects on the electrical and optical properties of semiconductor materials, therefore, high quality diamond materials are the key to ensure their semiconductor applications. Also for the growth of single crystal diamond substrate materials, high growth rates as well as large crystal sizes are required. To realize the semiconducting function of diamond, it needs to be effectively doped so that it has good n-type or p-type conductive properties. However, the current MPCVD preparation of single crystal diamonds is not yet able to meet the requirements of high performance semiconductor devices in terms of growth edge rate, material size, crystal size and semiconductor doping.