TCAD Simulation of the Effect of Buffer Layer Parameters on Single Event Burn-Out in p-GaN Gate HEMTs

The single event burn-out (SEB) performances of p-GaN gate high electron mobility transistors (HEMTs) were investigated in this article, considering different buffer electron mobilities and incident depths. The output, transfer, and breakdown curves of p-GaN gate HEMTs are not affected by the buffer electron mobility. However, a decrease in buffer electron mobility from 1350 to 265 cm (2)/(V center dot s) leads to an increase in SEB voltage from 340 to 460 V. After heavy ion impact, a significant number of electron-hole pairs are generated within the device. Gate breakdown occurs when the electric field at the gate exceeds the critical breakdown strength. Subsequently, an increase in device current is observed, leading to local temperature in HEMT up to 2000 K. The localized high temperature induces the occurrence of SEB. Heavy ion strikes into the buffer layer significantly deteriorate the SEB characteristics. As the incident depth of heavy ion increases, the transient current and device temperature increase correspondingly. Simulation results indicate that the buffer layer has a great effect on SEB characteristics of p-GaN gate HEMTs.