Numerical analysis of switching in the IGBT triggered thyristor

A monolithic power switching device structure for a MOS-controlled thyristor, called the IGBT (insulated gate bipolar transistor) triggered thyristor (ITT), is presented. In this device, a thyristor element is integrated into an IGBT structure and the minority carriers of the IGBT supply the trigger current of the thyristor. The target of this device is to achieve lower forward voltage than an IGBT without drastic deterioration of the turn-off characteristics. Numerical results on the ITT performance, and the on-state and the turn-off characteristics under inductive loads are described as compared with a conventional IGBT. Two-dimensional simulation results indicate that the forward voltage drop is lower than that of the IGBT and the MOS-gate turn-off capability is retained under inductive loads. The forward voltage drop at an on-state current of 100 A/cm² is 1.5 V, which is about 0.5 V lower than that of the IGBT, and the turn-off time is 0.19 μs, which is a little longer than that of the IGBT