Development of a Commercially Viable 4H-SiC PiN Diode Technology

The path to commercialization of the 4H-SiC PiN diode technology has been hampered by a fundamental problem with the forward voltage stability resulting from stacking fault growth emanating from basal plane screw dislocations (BPD). In this contribution, we highlight the progress toward producing stable high power devices with sufficient yield to promote commercial interest. Two independent processes, LBPD1 and LBPD2, have been shown to be effective in reducing the BPD density and enhancing the forward voltage stability while being compatible with conventional power device fabrication. Applying the LBPD1 and LBPD2 processes to 10 kV (20 A and 50 A) 4H-SiC PiN diode technology has resulted in a dramatic improvement in the total device yield (forward, reverse, and forward drift yields) from 0% to >20%. The LBPD1 process appears to be more robust in terms of long term forward voltage stability