The Theoretical Electrical Characteristics of Organic Thin Film Transistors Based on Capacitance Modulation

An electrical characteristic model of organic thin film transistors (OTFTs) is presented. The model is based on the capacitance modulation principle, i.e. the accumulated charges in the conductive channel are induced by the gate capacitance under an electric field. The current-voltage characteristics of the presented model are compared with the experimental data. According to the electrical characteristics of the model, it is explained that the operating process of OTFTs is actually modulated by the capacitance. The gate capacitance, the contact resistance, the contact barrier, and the field-effect mobility have a significant effect on the performance of OTFTs.