Gallium nitride (GaN) power devices have garnered attention in the anti-irradiation field owing to their excellent performance.

This study aims to explore the anti-γ-ray damage ability of gallium nitride power devices and clarify the mechanism of radiation degradation.

Firstly, the domestically produced commercial NP20G65D6 P-GaN gate enhanced AlGaN/GaN High Electron Mobility Transistor (HEMT) device was taken as test sample. Then, ⁶⁰Co γ-ray source with different irradiation doses of 0.3 Mrad (Si), 0.6 Mrad (Si), and 1.0 Mrad (Si), respectively, was employed to conduct total dose irradiation experiments under different bias (ON-state, OFF-state, and GND-state) conditions and annealing tests at different temperatures for enhanced AlGaN/GaN HEMT devices. Finally, the response law between the electrical performance of the device and the bias condition and annealing environment were analyzed to reveal the degradation mechanism of device sensitive parameters.

The results indicate that as the γ-ray irradiation dose increases, the device's threshold voltage exhibits a negative drift, and the transconductance peak, saturation leakage current, and reverse gate leakage current gradually increase. Simultaneously, the electrical characteristics of the device deteriorate more rapidly under the ON-state bias condition. Furthermore, annealing at high temperatures leads to a more apparent recovery of the electrical properties of devices. The analysis demonstrates that the higher the γ-ray irradiation dose, the more radiation defects are generated. The gate bias reduces the initial recombination rate of electron-hole pairs caused by irradiation, increases the number of holes escaping the initial recombination, and further increase the concentration of defect charge. The high-temperature environment causes tunneling annealing or thermal excitation annealing, which is conducive to the recovery of device performance.

The radiation damage process and mechanism of gallium nitride power devices of this study provides data support for evaluating and verifying its application in a space environment.