Irradiation effects in InGaAs/InAlAs high electron mobility transistors

The radiation tolerance of high electron mobility transistors (HEMTs) based on InGaAs/InAlAs lattice matched to InP has been studied. At low fluences of 3 MeV He+ ions, the only effect is a reduction in the leakage currents. At higher fluences, the drain current decreases, the threshold voltage incr eases toward zero, and the transconductance decreases. These results are co nsistent with increased trapping in the donor layer and increased scatterin g in the channel layer. Radiation-induced increases in the threshold voltag e occur three to nine times more slowly here than in GaAs/AlGaAs HEMTs, ind icating high radiation tolerance. (C) 2001 American Institute of Physics.