We report on the low-voltage-driven organic thin-film transistors (OTFTs) with various organic films [pentacene, tetracene, and copper-phthalocyanine (CuPc)] for the semiconductor channel on a thin poly-4-vinylphenol (PVP)/aluminum oxide (AlOx) bilayer gate dielectric. Quite a large capacitance of 31 nF cm2 and a high dielectric strength of ∼4 MVcm were achieved from the 45 nm thin polymer100 nm thick A1 Ox bilayer dielectric. All the organic channel layers deposited on the bilayer exhibited good crystalline quality as characterized by both X-ray diffraction (XRD) and atomic force microscopy (AFM) surface imaging because the bilayer had a smoothened and hydrophobic PVP surface on top. Our OTFTs with the bilayer dielectric exhibited good field-effect mobilities of 0.55, 0.07, and 0.004 cm2 V s for pentacene, tetracene, and CuPc channels, respectively, at a low operating voltage of less than -8 V.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Surfaces, Coatings and Films
- Materials Chemistry