Effect of 5 MeV proton radiation on DC performance and reliability of circular-shaped AlGaN/GaN high electron mobility transistors

Abstract

The authors report an investigation of the effect of different doses of 5 MeV proton irradiation on circular-shaped AlGaN/GaN high electron mobility transistors. The degradation of saturation drain current (I-DSS) was minimal up to an irradiation dose of 2 x 10 13 cm(-2). By comparison, a dose of 2 x 10 14 cm(-2) dose produced a 12.5% reduction of IDSS and 9.2% increase of sheet resistance. In addition, the threshold voltage showed larger positive shifts for 2 x 10 14 cm(-2) dose compared to 2 x 10 13 cm(-2), and both of these doses produced showed larger shifts for smaller gate to drain distances. Increases of 39.8% and 47.1%, respectively, in the breakdown voltage for 6 and 10 mu m drain to gate distances (L-GD) was observed and was attributed to the creation of a virtual gate at the AlGaN/GaN interface due to the irradiation, which reduced the peak electric field at the drain side of the gate edge. (C) 2014 American Vacuum Society.