Investigation of β-Ga₂O₃ Power Diodes with Failure Voltage of 300 V Under LET of 82 MeV·cm²/mg

This work demonstrates the single-event effects (SEE) hardness of β -Ga₂ O₃ power diodes featuring p-type NiO junction termination extension (JTE). The introducing of JTE relocated the sensitive position to decrease peak electric field under SEE and protect device from single-event burnout (SEB) early. The Schottky contact still suffered severe single-event leakage current (SELC) degradation during heavy-ion irradiation. Meanwhile, the numerous damage sites under Schottky contact were observed by scanning electron microscopy (SEM). Compared with the Schottky barrier diodes (SBDs), the NiO/ β -Ga₂ O₃ heterojunction diodes (HJDs) only exhibited negligible leakage current degradation till the SEB failure at reverse bias of 300 V under tantalum-ion irradiation with linear energy transfer (LET) of 82 MeV·cm²/mg. According to the electro-thermal coupling model, the heat spike on the surface of epitaxial layer generated by high electric field and current density resulted in SELC thermal damage of SBDs. For HJDs, the p-type region effectively relieved the hole accumulation in the epitaxial layer to alleviate electric field crowding, which enhanced the SELC tolerance. This work gives new insights on SEE mechanism and hardening method of β -Ga₂ O₃ power diodes.