Analytical models of ion-implanted GaAs FET's

This paper describes analytical models for the calculation of the current-voltage characteristics of ion-implanted GaAs FET's. The models, which take into account backgating, capping, the source and drain series resistances, and the output conductance, provide simple analytical expressions for the current-voltage characteristics and are quite suitable for the parameter acquisition and computer-aided design of GaAs FET's and IC's. In particular, the effective implanted charge and, hence, the activation efficiency may be deduced from the measured pinchoff voltage. The theory may be also used for optimization of doping profiles of GaAs FET's. The results of the calculation are in good agreement with experimental data.