Organic thin-film transistor bias-dependent capacitance compact model in accumulation regime

The authors present an analytical and continuous model for the total charges at the gate, drain and source electrodes for organic thin-film transistors (OTFTs), from which analytical expressions of the total capacitances are obtained. Under the quasi-static approximation, the model parameters are extracted using the previously developed unified model and parameter extraction method (UMEM). The capacitance model is valid above threshold voltage. It guarantees continuity of the expressions for the capacitance at the transition between linear and saturation regimes, as well as takes into account the overlap capacitance. Comparisons between modelled and experimental C_GG values are shown.