Split-Gate Power SiC MOSFET With P + Buffer for Enhanced Single-Event Radiation Hardness

Silicon carbide (SiC) power devices are attractive for space electrical systems due to superior blocking and switching characteristics, but the vulnerability to single-event radiation still limits their application. This article experimentally validates the enhanced single-event radiation hardness of the 1.2-kV split-gate SiC MOSFET with P+buffer (SG-PB-MOS) proposed in our earlier work. Numerical simulation reveals that the P+buffer suppresses the gate-oxide electric field and rapidly extracts the excess holes generated by the heavy-ion strike. Irradiation test was performed using181Ta${}^{{31}+}$ion with a large linear energy transfer (LET) of 85.91 MeV$\cdot $cm2/mg. The results show that the SG-PB-MOS achieves a comprehensive enhancement in irradiation hardness against latent gate damage (LGD), single-event leakage current (SELC), and single-event burn-out (SEB), and provides a substantially improved SEB threshold voltage than the conventional structure. The SG-PB-MOS has the potential to maintain robust operation under heavy-ion irradiation at 350 V drain–source bias and 15 V gate–source bias. Notably, these enhancements are achieved without adverse impact on the static or switching performance during normal operation. Along with the superior high-frequency and high-reliability performance, the SG-PB-MOS provides a device-level structural solution for radiation-intensive power electronic systems.