A 4H-SiC p-channel insulated gate bipolar transistor with higher breakdown voltage and superior V F·C res figure of merit

Abstract

A silicon carbide p-channel insulated gate bipolar transistor (IGBT) with higher breakdown voltage (BV) and low V F·C res figure of merit (FOM) has been simulated, fabricated, and characterized successfully. The proposed IGBT adds two n-type implant regions in the junction FET (JFET) area and increases the gate oxide thickness above the JFET area to reduce the reverse transfer capacitance (C res) and gate oxide electric field (E ox). The proposed structure notably lowers E ox below 3 MV cm−1 while elevating the BV to 16.6 kV. A new FOM of V F·C res is defined to evaluate the trade-off between the on-state and the C res characteristics. The experimental results demonstrate that a lower V F·C res FOM of 0.369 V·pF is achieved from the proposed IGBT with a reduction of 66.4%, compared to the conventional current spreading layer IGBT. Meanwhile, the simulated turn-on and turn-off times of the proposed IGBT are reduced by 29.4% and 20%, respectively.