Arbitrary density of states in an organic thin-film field-effect transistor model and application to pentacene devices

We present a modular numerical model for organic thin-film field-effect transistors (OTFTs) that allows for an arbitrary density of states to be independently defined for the semiconductor bulk and the semiconductor surface next to the gate insulator. We can derive the surface charge density dependence on the interface field as well as the space-charge-limited current characteristics. Together with a model of the contacts, we arrive at a physical model that is applied to a series of OTFTs in staggered inverted (top contact) geometry with various gate insulator treatments.