Oxygen plasma treatment and postaging of pentacene field-effect transistors for improved mobility

Abstract

The authors fabricated pentacene transistors with high mobilities by controlling the morphology of pentacene film through adjustments to the surface energy of the gate dielectrics with oxygen plasma treatment, and then by improving the interfacial properties through postaging. The increased surface energy of poly(methylmethacrylate) dielectric that results from the oxygen plasma treatment improves the interconnections between grains and enlarges the grain size. The postaging of transistors is presumed to rearrange the interface functional groups and as a result decrease the polar functionality without changing pentacene film morphology, which reduces the number of trap states and increases the mobility to 0.73 cm(2)/V s. (C) 2007 American Institute of Physics.