TCAD analysis of single-event burnout caused by heavy ions for a GaN HEMT

Abstract

Based on simulation, this work introduces the single-event burnout (SEB) results of P-GaN gate AlGaN/GaN high electron mobility transistors (HEMTs) and proposes a hardened structure with a PN junction connected to the drain in the buffer layer. The simulation results indicate that the SEB mechanism of P-GaN gate AlGaN/GaN-HEMTs is mainly related to the charge enhancement and the impact ionization process dominated by the high-field region near the drain. Electrons in the high-field region between the gate and drain can gain sufficient energy and generate electron–hole pairs in the high-field region near the drain during the collection process. The avalanche ionization process triggered by these electrons leads to a rapid increase in the electric field, ultimately causing the peak electric field at the drain side to exceed the critical electric field of the material, resulting in SEB. The proposed hardened structure (H-HEMT) effectively improves the SEB threshold voltage by improving the electric field distribution near the drain. Under the condition of linear energy transfer (LET) of 0.6\(pC/\mu m\) with heavy ion normal incidence, the SEB threshold voltage of the conventional structure (C-HEMT) is 230 V, while the H-HEMT can reach 420 V, showing better SEB resilience.