Analytical models of GaAs FET's

Abstract

We consider two analytical models for the calculation of the current-voltage characteristics of GaAs FET's. The first which we call a square law model provides an accurate description of GaAs FETs with low pinchoff voltages (less than 2 V or so for GaAs devices with a 1-µm gate) and an approximate description of GaAs FETs with higher pinchoff voltages, The second which we call a complete velocity saturation accurately describes high pinchoff voltage devices (higher than 3 V or so for GaAs FETs with a 1-µm gate), but cosiderably overestimates the drain-to-source current in low pinchoff voltage FET's.