Modeling of ambipolar a-Si:H thin-film transistors

Ambipolar hydrogenated amorphous silicon thin-film transistors are capable of both n- and p-channel device operation. Essential to the fabrication of such devices are ohmic source-drain contact regions and a high-quality low fixed charge gate insulator. A simple model has been developed to describe the output drain current versus drain voltage characteristics of these ambipolar devices, The model involves only the numerical integration of an interpolated sheet conductance function. By using the appropriate flat-band voltage, the model accurately predicts the experimental output drain current characteristics for both n- and p-type operation.