600V/20A 4H-SiC Schottky barrier diodes (SBD) were fabricated to investigatethe effect of key processing steps, especially before and after a formation ofSchottky contact, on the electrical performances of SBD and on a long-termreliability. The results show that 4H-SiC SBDs, subjected to a hydrogen-ambientannealing at 470oC for 10min and sacrificial treatment right after ionactivation, exhibited low forward voltage drop (VF) at a rated current of 20A,higher blocking voltage of 800V, and very short reverse recovery time of17.5ns. Despite a harsh reverse bias condition and temperature, a long-termreliability test shows that changes in forward voltage drop and reverse leakagecurrent (IR) were 0.7% and 8.9% and that blocking voltage was enhanced. This isattributed to a stabilized interface between passivation layer and SiC that iscaused by aging.
展开▼
