A comparison of charge dynamics in the reverse-conducting RC IGBT and Bi-mode Insulated Gate Transistor BiGT

In this paper we present the analysis of charge dynamics in the reverse conducting (RC)-IGBT and the Bi mode Insulating Gate Transistor (BiGT). The differences and similarities between the two device concepts are analyzed with the aid of 2D device simulations using a realistic 3.3kV device model. The influence of the anode shorts dimensioning and buffer design on the on-state characteristics and the snap-back effect is discussed and the advantages of the hybrid BiGT structure are demonstrated. It is shown that the application of the BiGT structure decouples the conventional RC-IGBT design trade-offs with respect to the diode and IGBT areas in relation to the snap-back effect. Main design principles for optimal IGBT and diode performance are outlined.