Organic thin-film transistor based on dibenzothiophene

Abstract

New channel material for organic thin film transistors using dibenzothiophene as the core and alkylbithiophene as side chains is synthesized by Suzuki coupling reaction of hexylbithiophene borate and dibromobenzothiophene. The obtained oligomer was characterized by FT-IR, mass and elemental analysis, UV-visible spectroscopy, cyclovoltammetry, differencial scanning calorimeter, and thermogravimetric analysis. Vacuum-evaporated film was characterized by X-ray diffraction and atomic force microscopy (AFM). It forms highly ordered polycrystalline vacuum-evaporated film. OTFTs using channel semiconductor of this nature exhibited excellent field-effect property, with mobility as high as 0.08 cm(2)/V, current on/off ratio to 10(5), and sub-threshold slope to 0.4 V/dec. The device exhibited very low subthreshold swing with less hysteresis. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.