Relevance of organic field effect transistor models: Simulation vs. experiment

Abstract

Some specifics of OFETs are not understood at present as e.g. a large subthreshold slope or a non-quadratic gate voltage dependence of the saturation current. We present a simulation study of OFET models with different types of gap states: (i) shallow acceptor doping, (ii) deep discrete traps, (iii) electron and hole traps distributed exponentially near the conduction and valence bands (equivalent to the a-Si thin film transistor). Comparison of the models with our experiments leads to conditions to evaluate the relevance of the models. Furthermore, effects are discussed which are related to the transistor design.