Refined Analysis of Leakage Current in SiC Power Metal Oxide Semiconductor Field Effect Transistors after Heavy Ion Irradiation

A leakage current is the most critical parameter to characterize heavy ion radiation damage in SiC MOSFETs. An accurate and refined analysis of the source and generation process of a leakage current is the key to revealing the failure mechanism. Therefore, this article finely tests the online and post-irradiation leakage changes and leakage pathways of SiC MOSFETs caused by heavy ion irradiation, analyzes the damaged location of the device in reverse, and discusses the mechanism of leakage generation. The experimental results further confirm that an increase in the leakage current of a device during heavy ion irradiation is positively correlated with the applied voltage of the drain, but the leakage path is not direct from the drain to the source. The experimental analysis of the source of the leakage current of the device after irradiation indicates that there is also a leakage current path between the device gate and source. The research results suggest that the experimental sample is more prone to a single-event gate rupture effect under this heavy ion radiation condition. The gate breakdown mainly occurs in the gate oxide layer at the neck region. This research can provide a theoretical basis for the radiation resistance reinforcement of SiC power devices.