1.4-kV Irradiation-Hardened β-Ga₂O₃ Heterojunction Barrier Schottky Diode Under 10⁷ ions/cm² Fluence and 82.1 MeV⋅cm²/mg LET Environments

Single event burnout (SEB) caused by heavy ion irradiation in space environments poses a significant threat to aerospace power electronic devices. This work demonstrates irradiation-hardened $\beta $ -Ga2O3 heterojunction barrier Schottky (HJBS) diodes with exceptional SEB capability. The device design incorporates micron-scale deep trenches filled by p-type nickel oxide (NiO) and high-k BaTiO3 field-plate (FP) edge termination. This architecture efficiently extracts radiation-induced positive charges (holes) during single-event irradiation through the trenched-embedded Ni/p-NiO with low Ohmic contact resistance, significantly alleviating charge aggregation while minimizing non-uniform field distributions through strategically engineered charge drainage pathways. As a result, the HJBS device achieves a SEB voltage exceeding 1.4 kV and a SEB degradation rate of only 9.6%. This is the first demonstration of kilovolt-class radiation-hardened diodes, and its performance metrics are the best reported among SiC, GaN, Ga2O3 and Si power diodes to date. This work underscores the great potential of Ga2O3 power diodes for irradiation power applications.