Insight about electrical properties of low-temperature solution-processed Al-doped ZnO nanoparticle based layers for TFT applications

Aluminium-doped zinc oxide nanoparticles (NPs) with controlled Al doping contents (AZO(X) with x = 0-0.8 at% of Al) were explored as new oxide semiconductor materials to study the impact of doping on both solution and solid states. Polycrystalline AZOX thin films were produced by spin-coating the dispersions following by a thermal post-treatment at low-temperature (80 degrees C or 150 degrees C). The coated AZO(X) films were employed as active layer in thin-film transistors. Morphology and microstructure were studied by scanning electron microscopy and X-ray diffraction. The impact on the device performances (mobility, conductivity, charge carrier density) of Al-doping content together with the solution state was examined. Spin-coated films delivered an electron mobility up to 3 x 10(-2) cm(2)/Vs for the highest Al-doping ratio AZO(0.8). Despite highly different morphologies, extrinsic doping with aluminium significantly increases the conductivity of low temperature solution-processed AZO(X) NPs series based layers by several orders of magnitude from AZO(0) to AZO(0.8). (C) 2016 Elsevier B.V. All rights reserved.