MAT Collaboration Meeting 2026

Silicon carbide (SiC) power devices are promising for space applications but suffer from single event leakage current (SELC), single event burnout (SEB) and single event gate rupture (SEGR) under heavy ion irradiation. Our recent experimental and simulation studies have systematically investigated the mechanisms including heavy ion induced degradation in SiC junction barrier Schottky (JBS) diodes and power MOSFETs. In SiC JBS diodes, a graded buffer layer between epitaxy and substrate suppresses the electric field peak at the interface, raising the SEB threshold. Substrate thinning from 350 μm to 150 μm similarly reduces damage by lowering impact ionization and charge deposition. In SiC MOSFETs, increasing ion incidence angle mitigates both oxide and body damage. With varying gate oxide thicknesses, i.e. 48 nm and 56 nm, the experiments reveal that thicker oxide reduces gate to drain leakage but promotes drain to source leakage, indicating radiation damage redistribution rather than simple suppression. High resolution TEM directly observes nanoscale amorphous damage and atomic mixing at the Schottky interface, confirming localized melting as the reason cause of SELC. The combination of experimental characterization, TCAD simulations, and nanoscale material analysis provides a way for understanding heavy ion induced degradation and guiding radiation hardened design for power electronics devices.