Influence of organic gate dielectrics on the performance of pentacene thin film transistors

The electronic transport of polycrystalline pentacene thin film transistors is investigated. The thermally evaporated pentacene films prepared on organic dielectrics like benzocyclobutane exhibit mobilities comparable with inorganic dielectrics like thermal oxide and plasma enhanced chemical vapor deposited silicon nitride. To gain insights in the electronic transport behavior of the organic thin film transistors (TFTs) the I/V characteristics were simulated by a one-dimensional density-of-states transistor model. The experimental data can be described by using a broad distribution of acceptor-like states deep in the bandgap and a narrow distribution of donor-like states close to the valance band. The influence of the different dielectrics on the defect distribution and the electronic transport will be discussed.