Solution-processible high-permittivity nanocomposite gate insulators for organic field-effect transistors

We report on solution-processible high permittivity nanocomposite gate insulators based on BaTiO(3) nanoparticles, surface-modified with a phosphonic acid, in poly (4-vinylphenol) for organic field-effect transistors. The use of surface-modified BaTiO(3) nanoparticles affords high quality nanocomposite thin films at large nanoparticle volume fractions (up to 37 vol %) with a large capacitance density and a low leakage current (10(-8) A/cm(2)). The fabricated pentacene field-effect transistors using these nanocomposites show a large on/off current ratio (I(on/off) 10(4)-10(6)) due to the high capacitance density and small leakage current of the gate insulator. (C) 2008 American Institute of Physics.