Enhancement of hole injection in pentacene organic thin-film transistor of O-2 plasma-treated Au electrodes

Abstract

The effect of oxygen plasma treatment on enhancement of hole mobility was demonstrated using pentacene organic thin-film transistors (OTFTs) with bottom-contact Au electrodes. Linear field-effect mobility increased from 3.2x10(-2) to 7.4x10(-2) cm(2)/V s as the Au electrodes were treated with O-2 plasma. Secondary electron emission spectra revealed that the work function of oxygen plasma-treated Au is 0.5 eV higher than that of untreated Au. This led to a reduced hole injection barrier at the interface of Au with pentacene, increasing the field-effect mobility of OTFTs. (c) 2006 American Institute of Physics.