Numerical simulation of p-type diamond Schottky barrier diodes for high breakdown voltage

Abstract

P-type diamond devices have high potential for power semiconductors due to their high critical field, hole mobility, and thermal conductivity. The electrical characteristics of p-type pseudovertical diamond Schottky barrier diodes (SBDs) were investigated by numerical simulation. The impact ionization coefficients were required to obtain the breakdown voltage. They were revised to satisfy a parallel-plane breakdown field of 10MV/cm. The doping concentration and thickness of a low-doped drift layer were key parameters in determining the parallel-plane breakdown voltage. The p-type pseudovertical diamond SBDs exhibited lower breakdown voltage than the parallel-plane breakdown voltage because field crowding occurred at the edge of the cathode. When the doping concentration and thickness of the p- drift layer were 10(16)cm(-3) and 4 mu m, respectively, the breakdown voltage of the p-type pseudovertical diamond SBD was 961V, which was considerably less than the parallel-plane breakdown voltage of 3646V. (C) 2017 The Japan Society of Applied Physics