3.3kV SBD-Embedded SiC-MOSFET Module for Traction Use

Abstract:
We have developed a 3.3kV Schottky-barrier-diode-embedded (SBD-embedded) silicon-carbide metaloxide-semiconductor field-effect transistor (SiC-MOSFET) module for traction use. It achieves 60% lower switching loss compared to the conventional 3.3 kV full-SiC module. It also outperforms the conventional module in output current across all frequencies, with 40% improvement at 3 kHz. The SBDembedded SiC-MOSFETs ensure high reliability by preventing bipolar degradation. We have introduced a novel structure, the bipolar mode activation (BMA) cell, to enhance surge current capability, achieving a similar level to body-diode-operated SiC-MOSFET modules. The required BMA area is 0.2% of the chip area and does not affect electrical characteristics within the safe operating range. Continuous current and repetitive surge tests confirm the robustness to bipolar degradation of our SBD-embedded SiCMOSFETs. Additionally, our module exhibits excellent moisture resistance according to the High Voltage High Humidity High Temperature Reverse Bias (HV-H3TRB) test based on ECPE guidelines.