A comparison of the switching behavior of IGBT and MCT power devices

Measured and simulated turn-off curves of high-voltage MCTs (MOS-controlled thyristors) and IGBTs (insulated-gate bipolar transistors) are presented. Device simulation results show that the inherently faster-switching IGBT is much more affected by dynamic avalanche phenomena than the MCT. It is also shown that the avalanche-injected carriers can be removed by shorting the anode layer, resulting in a much higher turn-off performance for both devices. Because of the lower charge and therefore the higher dV/dt, the ionization rate is higher in the IGBT than in the MCT.<<ETX>>