Comparative Investigation on Ionizing Irradiation- Induced Threshold Voltage Degradation for 1200-V DT SiC MOSFET by Experiment and Simulation

Threshold voltage ( $V_{\text {TH}}$ ) degradation mechanisms induced by the ionizing irradiation for the 1200-V double-trench (DT) silicon-carbide (SiC) metal-oxide semiconductor field-effect transistor (MOSFET) are investigated. The ionizing irradiation experiment is performed with different gate-source voltages ( $V_{\text {GS}}$ ) and total ionizing doses (TIDs). The maximum $V_{\text {TH}}$ shifts are −1.92 V for a $V_{\text {GS}}$ of 0 V and a TID of 500 krad(Si), and −4.73 V for a $V_{\text {GS}}$ of 20 V and a TID of 150 krad(Si), respectively. A novel method of investigation on TID-induced $V_{\text {TH}}$ shift from energy domain and numerical simulation with the aid of the TCAD tool is exploited. Extensive simulations indicate that donor-like oxide traps with energy larger than 0.55 eV dominate the negative $V_{\text {TH}}$ shift. The summation of two Gaussian distribution models is used to emulate trapped hole energy distribution, and the relative errors between measured and simulated $V_{\text {TH}}$ shifts are within ±13.36% at a TID of 100 krad(Si).