Study of Passivation Layer on Bevel Edge Termination for SiC RSD

Abstract

The passivation technology for the bevel edge termination of SiC RSD(reversely switched dynistor) is studied in this paper. The influence of SiO2 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 SiO2 layer deposition by PECVD can reduce the leakage current while annealing in N2 atmosphere has no apparent effect.