Effect of proton irradiation on thermal resistance and breakdown voltage of InAlN/GaN high electron mobility transistors.

InAlN/GaN high electron mobility transistors were irradiated from the front side with 340keV protons to a dose of 5 × 10¹³ cm^-2. Raman thermography showed that the irradiated devices had higher channel temperatures than unirradiated control devices, but only by ~10% under typical biasing conditions. Accordingly, the irradiated devices have higher thermal resistance (400°C/W) compared to reference devices (350°C/W), based on the slope of the power versus channel temperature line. However, increases of 42% in off-state drain breakdown voltage (V_BR) and of >92% in critical voltage (V_cri) were observed for the proton irradiated HEMT. This is ascribed to the reduction of the peak electric field at the gate edges by ~50% through the introduction of negative trap charges created from vacancies generated by the proton irradiation. [ABSTRACT FROM AUTHOR]