(Invited) Failure Mechanisms in AlGaN/GaN HEMTs Irradiated with 2MeV Protons

Abstract

GaN high electron mobility transistors (HEMTs) have shown the potential to be extremely tolerant of the space radiation environment. AlGaN/GaN HEMT structures on three different substrates were exposed to proton irradiation at fluences up to 6x1014 cm-2, which resulted in a 30% reduction in mobility and saturation current density. Dynamic ON-resistance measurements demonstrated increased degradation by a factor of 10 under off-state quiescent voltage stress conditions. High resolution transmission electron microscopy revealed a radiation-induced void under the gate metallization, indicative of a Kirkendall effect.