Research on microwave mode and coupling energy in plasma reactor design for MPCVD diamond

Systematic research on the performance of former designed plasma reactor was carried out in this paper. Numerical simulation method was performed, the distribution of electromagnetic field in microwave cavity by Finite Element Method (FEM). Microwave mode in waveguide, coaxial transformation part and plasma reactor were studied, they are TE10, TEM and TM021 respectively. The impact factor of microwave coupling efficiency was studied. The research results show that, the shape of interconnection between the inner conductor of the antenna and the substrate holder has influence on microwave coupling efficiency. The coupling energy is different when the radius of coaxial conductor was changed, but with the same microwave resonate mode inside the cavity. The research results will provide theory basis for the improvement of device for diamond film deposition, it is also very meaningful for the development of MPCVD technique.