The　irradiation　and　postirradiation　annealing　responses　of　SiC　metal-oxide-semiconductor　field-effect　transistors　(MOSFETs)　are　investigated　under　the　application　of　different　positive　gate　biases.　During　irradiation,　the　threshold　voltage　of　the　SiC　MOSFETs　showed　a　negative　shift　under　the　application　of　a　positive　gate　bias.　However,　a　significant　reduction　in　this　shift　was　observed　as　the　positive　gate　bias　increased　from　20　to　24　V.　The　postirradiation　annealing　of　the　irradiated　SiC　MOSFETs　was　performed　under　various　positive　gate　biases　over　the　range　from　32　to　44　V.　A　rapid　reduction　in　the　number　of　oxide-trapped　charges　was　observed.　These　results　indicate　that　the　degradation　of　the　threshold　voltage　in　irradiated　devices　can　be　inhibited　by　the　application　of　a　higher　gate　voltage,　while　the　high　positive　gate　bias　annealing　represents　an　efficient　way　to　recover　the　threshold　voltage　shift　in　these　devices.