An analytical model for a-Si:H transistors based on TFT device characteristics

The authors present a simple analytical model which is targeted for the design of AMLCD driver circuits. The model achieves excellent agreement with experimental data by modeling the TFT current as the summation of two components: a surface and a bulk component. The equations that describe this current-voltage behavior are presented. In order to model the transistor in the saturation region, a simple expression for channel length modulation is utilised. The model uses four device parameters that are obtained from direct measurements of the a-Si:H TFT characteristics: the mobility, the threshold voltage and two physically based parameters to account for bulk conduction and channel length modulation. These parameters are used for quick calibration of the model to any TFT fabrication process