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

Threshold voltage (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {TH}}$ </tex-math></inline-formula>) 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 (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {GS}}$ </tex-math></inline-formula>) and total ionizing doses (TIDs). The maximum <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {TH}}$ </tex-math></inline-formula> shifts are −1.92 V for a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {GS}}$ </tex-math></inline-formula> of 0 V and a TID of 500 krad(Si), and −4.73 V for a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {GS}}$ </tex-math></inline-formula> of 20 V and a TID of 150 krad(Si), respectively. A novel method of investigation on TID-induced <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {TH}}$ </tex-math></inline-formula> 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 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {TH}}$ </tex-math></inline-formula> shift. The summation of two Gaussian distribution models is used to emulate trapped hole energy distribution, and the relative errors between measured and simulated <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text {TH}}$ </tex-math></inline-formula> shifts are within ±13.36% at a TID of 100 krad(Si).