Low dI_C/dt noise and on-state voltage 4H-SiC IGBT with N-barrier layer

Abstract A novel 4H-SiC insulated-gate bipolar transistor (IGBT) with an N-barrier layer (NBL) at the top side of the P-shield region is proposed. During the turn-on transient, compared with the conventional grounded asymmetric P-shield trench (GASY) IGBT, the NBL IGBT has lower turn-on d I C / d t and peak turn-on current ( I surge ) due to the introduction of the N-barrier layer. Consequently, the NBL IGBT has lower electromagnetic interference noise based on good turn-on d V / d t controllability. The simulation results show that the reverse recovery d V KA / d t ( V KA is the cathode-anode voltage between the freewheeling diode (FWD), as shown in Fig. 1) of the FWD of the NBL IGBT is 54.6% lower than that of the GASY IGBT for the same turn-on loss ( E ON ). In the on-state, compared with the GASY IGBT, the NBL IGBT has one more channel, and the N-barrier layer also blocks part of the holes. Thus, the conductivity modulation effect can be enhanced and the on-state voltage ( V ON ) can be reduced. The simulation results show that V ON of the NBL IGBT is 14.4% lower than that of the GASY IGBT at 30 A on-state current. In addition, the proposed IGBT has no additional complex structure, so it is simple to manufacture and does not increase the production cost.