Prediction of parameter variation in Schottky barrier field effect transistors on GaAs

Abstract

It is shown that for Schottky-barrier field-effect transistors based on three-layer GaAs structures (film – buffer layer – substrate), the parameter spread caused by the nonuniform distribution of deep centers across the wafer can be characterized by a single quantity: the effective concentration of unoccupied deep centers at the film – buffer layer interface. This parameter reflects the integral influence of deep centers in both the buffer layer and the substrate on current transport in the film and can be determined from the low-frequency capacitance–voltage characteristic.