Switching Characteristics of SiC-MOSFET and SBD Power Modules

Prototype SiC power modules are fabricated using our class 10 A, 1.2 kV SiC-MOSFETs and SiC-SBDs, and their switching characteristics are evaluated using a double pulse method. Switching waveforms show that both overshoot and tail current, which induce power losses, are suppressed markedly compared with conventional Si-IGBT modules with similar ratings. The total switching loss (MOSFET turn-ON loss, turn-OFF loss and SBD recovery loss) of SiC power modules is measured to be about 30% of that of Si-IGBT modules under the generally-used switching condition (di/dt ~250A/μs). The three losses of SiC modules decrease monotonically with a decrease in gate resistance, namely switching speed. The result shows the potential of unipolar device SiC power modules.