Stability Evaluation of Insulated Gate AlGaN/GaN Power Switching Devices Under Heavy-Ion Irradiation

Depletion mode insulated gate AlGaN/GaN power switching HEMTs were evaluated for stability under heavy-ion irradation. Experiments were performed for different types of heavy-ion species, values of gate bias, drain bias, and device geometry. For the insulated gate AlGaN/GaN devices, an as-of-yet unobserved single-event occurred, which we have termed single-event switching (SES). These SES events occurred next to previously observed single-event gate rupture (SEGR) events. It was found that the SES events were gate leakage dependent and stopped occurring above a certain threshold value of gate leakage. Statistical analysis showed that the cross section for single SES events exhibited a lognormal distribution with a median value close to the gate area, and the capture cross section exhibited a slight voltage dependence. The gate leakage after irradiation, on the other hand, was exponentially distributed and was strongly voltage and geometry dependent, indicating an electric field dependency.