Influence of Carrier Lifetime on Silicon Carbide Power Devices for Pulsed Power Application

In this paper, we investigate the influence of carrier lifetime on SiC GTO and PiN devices for pulsed power application. Both the device characteristics and the circuit dynamic performance in pulsed discharging system are studied based on simulation and experiments. The influence of tau(HL) on the static and dynamic discharging characteristics in both single- and multi-stage pulsed power network (PFN) are analyzed by extensive mix-mode simulation considering thermoelectric effect within SiC devices. Simulation results show that the SiC GTO is more sensitive to carrier lifetime and induces the power dissipation 10X higher than that of SiC PiN during pulsed discharging. The discharging capability of SiC GTO decreases for tau(HL) < 0.4 mu s. The heat generates in the drift region and tends to shift towards the top anode region in long pulse width discharging. The simulation is demonstrated by experimental data of our fabricated SiC GTOs.