Degradation induced by 2-MeV alpha particles on AlGaN/GaN High Electron Mobility Transistors

We studied the degradation of AlGaN/GaN High Electron Mobility Transistors (HEMT) after 2-MeV alpha irradiation for two different fluences, namely 1013 a/cm2 and 1014 a/cm2. After the exposure and depending on the irradiation fluence, we observed a drop both in drain current and transconductance, and a reduction in the leakage current of the gate diode. We attributed these effects to bulk damage, radiation-induced formation of deep-level trap sites in the channel layer, and doping compensation/removal in the barrier layer.