Influence of field plate terminal on the electric field distribution and breakdown characteristics of diamond SBD

Numerical simulation model of field plate termination diamond Schottky barrier diode(SBD) was established in this paper, the influence of the field plate length L, insulating layer thickness T_OX, substrate doping concentration N_B, and the structure shape of the field plate on the electric field distribution inside the device and the influence of breakdown voltage of diamond SBD were numerical simulated by Silvaco device simulation tools ATLAS. The results of numerical simulation were analyzed and explained physically. The breakdown voltage increases with the increasing length of the field plate within the range of 0.0 to 0.2 μm when T_OX=0.4 μm and N_B=10¹⁵ cm^-3, and decreases when L>0.2 μm. The breakdown voltage increases with the increasing of insulating layer thickness T_OX within the range of 0.1 to 0.4 μm when L=0.2 μm and N_B=10¹⁵ cm^-3, and decreases when T_OX>0.4 μm. The breakdown voltage of the device reaches its maximum 1 873 kV when L=0.2 μm, T_OX=0.4 μm, and N_B=10¹⁵ cm^-3. The steps field plate can effectively improve the breakdown voltage of the device, compared with the ordinary field plate structure.