Organic thin-film transistor compact model with accurate charge carrier mobility

A physical compact charge carrier mobility model for undoped-body organic thin-film transistors (OTFTs) based on an analysis of the bias-dependent Fermi-energy movement in the band gap is reported. Mobility in localized- and extended-energy states predicts the current transport in week- and strong-inversion regimes, respectively. A hopping mobility model as a function of surface potential is developed to describe the carrier transport through localized trap states located in the band gap. The Poole-Frenkel field effect mechanism is considered to interpret the band-like carrier transport mechanism in extended energy states. Modeled results are compared with the measured DNTT-based high-performance OTFTs data to verify the model.