Performance evaluation of silicon carbide devices in power converters

Commercial silicon carbide (SiC) Schottky and PIN diodes, and JFETs were characterized for static conduction and dynamic switching performances in hard- and soft-switching buck converters. The results are compared with the measured data obtained from similarly rated silicon and GaAs devices. It is shown that for low-voltage rectifiers the only real advantage of SiC over silicon and GaAs is the potential for high-temperature operation. A significant improvement in reverse recovery performance was measured for high-voltage SiC PIN diodes compared to silicon PIN diodes. Low-voltage SiC JFETs were found to perform poorly in power converters compared to similarly rated silicon power MOSFETs. It is shown that further technology optimization could make SiC JFETs attractive candidates for high-power high-temperature high-frequency electronics switching.