The Simulation Breakdown Characteristic of 4H-SiC SBD with Field Rings

According to the avalanche impact ionization theory, the field rings(FR) edge termination technology is introduced to the 4H-SiC SBDs in order to improve the breakdown voltage speciality. This paper investigates the theory and the effect of field ring edge termination structures, and then made a numerical optimization using a two-dimensional device simulator ISE-TCAD. The simulation results show that variety parameters including spacing, doping concentration, implantation depth and the numbers of FR can have influence on the breakdown voltage.