Study of Passivation Layer on Bevel Edge Termination for SiC RSD

The passivation technology for the bevel edge termination of SiC RSD(reversely switched dynistor) is studied in this paper. The influence of SiO 2 passivation layer on electrical characteristics of SiC RSD is analyzed. The relationship between interface charges and blocking voltage is simulated. The feasibility of depositing a passivation layer on the bevel is verified. Several processes are conducted in order to reduce the interface charges and the I-V measurement shows that thermal oxidation and SiO 2 layer deposition by PECVD can reduce the leakage current while annealing in N 2 atmosphere has no apparent effect.