The influence of donor neutralization on the transfer characteristics of MODFET's at 77 K: Theory and experiment

Calculations and experiments on GaAs/AlGaAs MODFET's at 77 K show that due to neutralization of the relatively deep donors an increase in gate voltage will neither increase the two-dimensional electron concentration nor introduce free electrons into the AlGaAs for some range of gate voltages. The corresponding leveling off of drain saturation current is more pronounced in depletion- than in enhancement-mode devices.