High current 6 kV 4H-SiC PiN diodes for power module switching applications

Forward voltage (V-F) drift, in which a 4H-SiC PiN diode suffers from an irreversible increase in VF under forward current flow, continues to inhibit commercialization of 4H-SiC PiN diodes. We present our latest efforts at fabricating high blocking voltage (6 kV), high current (up to 50 A) 4H-SiC PiN diodes with the best combination of reverse leakage current (I-R), forward voltage at rated current (V-F) and V-F drift yields. We have achieved greater than 60% total die yield on-wafer for 50 A diodes with a chip size greater than 0.7 cm(2). A comparison of the temperature dependent conduction and switching characteristics between a 50 A/6 kV 4H-SiC PiN diode and a commercially available 60 A/4.5 kV Si PiN diode is also presented.