Neutron degradation of the I-V characteristics of AlGaAs/GaAs modulation-doped field-effect transistors

AlGaAs/GaAs MODFETs have been neutron-irradiated to fluences approaching 10¹⁵ cm^-2. The source-drain current and the transconductance degrade about 30% over this range of fluences. The source-drain resistance increases by 60% and the end resistance increases by 30% at fluences near 10¹⁵ cm^-2. A triangular-well one-subband depletion layer model which applies over the range of I-V characteristics from subthreshold to saturation has been developed. The model has been extended to describe neutron degradation of source-drain current and transconductance. Both the source-drain current and the transconductance exhibit a nonlinear dependence on neutron fluence, which is reflected in the theoretical results