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 increases toward zero, and the transconductance decreases. These results are consistent with increased trapping in the donor layer and increased scattering in the channel layer. Radiation-induced increases in the threshold voltage occur three to nine times more slowly here than in GaAs/AlGaAs HEMTs, indicating high radiation tolerance. (C) 2001 American Institute of Physics.