Mono-Energetic Proton Induced Damages in SiC Power MOSFETs

The mechanisms of single event burnout (SEB) are investigated for SiC MOSFETs by proton irradiation with varying energies. The material melting due to thermal runaway is observed at the damage region for the device with SEB. The proton energy is proved to be a key factor to affect SEB. The proton induced SEB cross-section is higher for higher energy proton irradiation. The information of the secondary ions is obtained through Monte Carlo simulations to explain this phenomenon. The occurrence of SEB depends on the LET value and range of the secondary ions. The relations between SEB and quasi-stationary avalanche characteristics for SiC MOSFET are verified by TCAD simulations. SEB phenomenon actually origins from the secondary breakdown caused by charged ion injection. So the drain bias voltage during irradiation is very important to determine whether SEB occurs.