Novel hybrid PVA–InZnO transparent thin films and sandwich capacitor structure by dip coating method: preparation and characterizations

Abstract

Novel hybrid poly(vinyl alcohol)–indium zinc oxide (PVA–InZnO) thin films were prepared by a simple and cost effective dip coating method and Al/PVA–InZnO/Al sandwich capacitor structure was prepared by using thermal evaporation and dip coating methods. Fourier transform infrared spectra showed the characteristic peaks correspond to metal–oxide bonds present in the films. The X-ray diffraction patterns revealed the existence of mixed phase cubic In₂O₃ and hexagonal wurtzite ZnO with polycrystalline structure. The scanning electron microscope images showed uniform distribution of In₂O₃ and ZnO nanoparticles over the entire film surface. High transmittance (50 to 80%), low absorbance, wide band gap energy (4.1 to 3.75 eV) and low α and k were obtained from an optical study. High dielectric constant, low dielectric loss and low activation energy were obtained from Al/PVA–InZnO/Al. The obtained results suggested that these prepared hybrid thin films could be used as hybrid gate dielectric layer in transparent organic thin film transistors (T-OTFT's) and in opto-electronic devices in the near future.