Study of single event effect failure mechanism in P-GaN HEMTs based on experimental and TCAD simulation

Abstract

This study systematically investigates the Single Event Burnout (SEB) mechanism of p-GaN gate AlGaN/GaN HEMTs. The experiment used 500 MeV Kr ions to vertically irradiate the device surface, with the 3 × 10³ cm⁻²/s flux and total radiation fluence of 1 × 10⁶ cm⁻². during which a significant increase in both drain current and gate current was observed. As the drain bias increased, devices failed in two scenarios: irreversible drain leakage and catastrophic burnout. Potential burnout mechanisms were explored through Technology Computer-Aided Design (TCAD) simulations. The study suggests that when heavy ions strike the device, electron-hole pairs are generated. Electrons move under a high transverse electric field and are quickly extracted by the drain, causing a significant rise in drain temperature, which leads to permanent damage. Additionally, charge accumulation at the drain edge induces a localized transient high electric field, exceeding the intrinsic breakdown fields of GaN and AlGaN. Although this localized high electric field lasts for only a short duration, it inevitably damages the device. The burnout locations observed under a scanning electron microscope are consistent with the proposed Single-event burnout (SEB) mechanism. This study provides important theoretical and experimental support for assessing the reliability of GaN power devices against high-energy single-event burnout in space applications.