Impact of the SiC MOSFET Body Diode in Heavy Ion-Induced Single-Event Damage

To investigate the influence of the body diode on the single-event effect of SiC MOSFETs, a structure with a wider body diode region (WB-MOSFET) is designed compared with a conventional MOSFET (C-MOSFET). Krypton (Kr) and tantalum (Ta) ion irradiation experiments showed that the WB-MOSFET exhibited a slightly higher drain bias$(V_{\text{DS}})$leading to single-event leakage current (SELC) degradation compared to the C-MOSFET. Meanwhile, during the SELC I degradation stage, the gate leakage current$(I_{\text{GSS}})$at the same$V_{\text{DS}}$was less than 20% of that in the C-MOSFET. But at higher$V_{\text{DS}}$corresponding to the SELC II degradation stage, the WB-MOSFET showed a significant increase in drain leakage current$(I_{\text{DSS}})$. This increase was associated with body diode degradation, likely caused by an electric field surpassing the critical breakdown field of SiC within 10 ps of heavy-ion incidence. Additionally, the$\mathrm{P}^{+}$implant region was found to be more sensitive in SELC II degradation stage than the Pwell implant region.