Irradiation Hardened p-GaN HEMTs Enabling 558 V Single-Event Hardness at 75.7 MeV⋅cm2/mg and 95% Conversion Efficiency at 300 W/500 kHz

This work demonstrates the robust single-event irradiation hardness in 650-V E-mode p-GaN HEMTs with source-connected buried metal structure. Such device design notably contributes to the removal of irradiation-induced holes accumulated in the reverse-biased p-GaN/ AlGaN/GaN (p-i-n) junction region, thereby improving irradiation robustness against single-event burnout (SEB). The resulting device exhibits significantly improved SEB voltages of 558 and 467 V under heavy ion linear energy transfer (
$LET_{\text {ion}}$
) conditions of 75.7 and 86.3 MeV
$\cdot $
cm2/mg, respectively, setting a new performance record for GaN-based power devices. Moreover, based on pulsed laser equivalent heavy ion irradiation system configured with a power switching circuit, a high power conversion efficiency of 95% is demonstrated under 77.6 LET PL, 300 W/500 kHz conditions. This work thus makes a significant step toward reaching the promise of GaN devices for radiation applications.