Oxide Damage Induced Leakage Current Degradation in SiC MOSFETs during Heavy-ion Irradiation

Abstract

This paper presents the experimental characterization of SiC MOSFETs exposed to the heavy-ion irradiation. Different leakage paths related to the drain bias used during the tests are observed, suggesting different damage sites in the devices, which can be further verified through the post-irradiation measurements. TCAD simulations are utilized to explore the failure mechanisms. It is shown that the gate oxide damage firstly occurs in the middle of the JFET region, while gradually spreads to the channel region with the increase of biased drain voltage, and terminates at the source region eventually. The findings in this paper demonstrate that more attentions should be paid on the heavy-ion induced gate oxide damage before SiC MOSFETs could act as a drop-in replacement of Si-based counterparts in avionic applications.