Measurement of Total Ionizing Dose Effects on SiC Trench MOSFETs by Gamma-ray and Alpha-particle Irradiation

We measured total ionizing dose effect (TID) on Si, SiC planar and SiC trench power MOSFETs by using Co-60 $\gamma$-ray source and 241Am $\alpha$-particle source. Measurement results show that SiC power MOSFETs have higher tolerance to $\gamma$-ray irradiation. In contrast, the SiC trench MOSFET is most vulnerable to $\alpha$-particle-induced TID. Threshold voltage shift, $\triangle V_{\mathrm{t}\mathrm{h}}$ of the SiC trench MOSFET is -4.SV after 150 krad $\alpha$-particle irradiation, which is 12.6% larger than that in the Si MOSFET. In this measurements, the SiC planar MOSFET has the highest tolerance for both $\alpha$-particle and $\gamma$-ray irradiation. $\Delta V_{\mathrm{t}\mathrm{h}}$ of the SiC planar MOSFET is 1/20 or less than that of the Si MOSFET.