A reduced complexity process for organic thin film transistors

A simplified device structure for depletion-mode organic thin film transistors is described in which the gate electrode and the source/drain contacts are prepared in the same process step, thus reducing the number of material depositions and photolithography steps. Based on the simplified device structure and using the small-molecule aromatic hydrocarbon pentacene as the active material, organic thin film transistors were fabricated on glass substrates with carrier mobility of 0.6 cm2/V s, on/off current ratio of 105, and subthreshold slope of 0.5 V/decade.