Effect of Fixed Oxide Charges and Donor-Like Interface Traps on the Breakdown Voltage of SiC Devices with FGR and JTE Terminations

The influences of positive fixed oxide charges and donor-like interface traps on breakdown voltages of SiC devices with FGR and JTE terminations were studied. The breakdown voltages of devices with both FGR and JTE terminations were found to degrade when the level of fixed oxide charges overs 1×1012 cm-2 due to enhancement of junction curvature by fixed oxide charges. The introduction of donor-like interface traps at the interface shows similar behaviors as fixed positive charges, suggested that both fixed oxide charges and interface traps should be taken into account when one optimizes device designs and processes.