NUMERICAL SIMULATIONS OF AMORPHOUS-SILICON THIN-FILM TRANSISTORS

In this paper we present results of two-dimensional numerical simulations of low voltage, high voltage, and vertical amorphous silicon transistors. The model input consists of one realistic density of states spectrum for undoped amorphous silicon, and one self-consistent set of model parameters for all devices. Our results are in good agreement with experimental data, and this good fit is based on a new model for the source and drain contacts. Our approach is to treat these contacts as consisting of a fixed resistance in series with a small potential barrier whose height is modulated by current flow. Finally we show that relatively small changes in the density of deep localized states significantly alter the simulated device characteristics.