The Degradation and Recovery of 1200-V SiC MOSFET with Different Total Ionizing Doses

The cobalt irradiation experiments of the 1200V/20A rated silicon carbide (SiC) metal-oxide-semiconductor field-effect- transistor (MOSFET) were carried out under different total ionizing doses (TIDs). The shifts of the key electrical parameters, such as threshold voltage, on-resistance, breakdown voltage, and gate capacitance, were measured after irradiation and annealing processes. The mechanism for the effect of gate voltage on the radiation degradation of the devices was analyzed, and the room temperature annealing recovery was also explored. The results showed that the generated holes during irradiation were trapped in the oxide layer and SiO2/SiC interface, resulting in the degradation of the electrical parameters. The gate voltage affected the final yield of oxide-trapping charge, which leads to the difference of the degradation degrees of the devices after irradiation. Due to the relaxation of the oxide-trapping charge during the annealing process, the device electrical properties were partially recovered.