Low temperature synthesis and optical and electrical characterization of ZnO thin films

Zinc oxide (ZnO) thin films were synthesized by the sol-gel dip coating method using zinc sulphate as the precursor material of ZnO and Sodium Lauryl sulphate as a surfactant. The films were annealed at 450 degrees C and subjected to structural, optical and electrical characterization. X-ray diffraction (XRD) spectra confirmed the hexagonal wurtzite phase of ZnO. The crystallite size was estimated by the Scherrer's method. The optical transmittance was measured using UV-Visible spectrophotometer and the optical band gap energy was estimated by the Tauc's method and found to be 3.3 eV. Photoluminescence (PL) spectra of ZnO films was studied using spectroflurometer and a weak UV and a broad visible emission bands were observed. The variation in the DC conductivity of the ZnO film with temperature was studied and confirmed the semiconducting behavior of the ZnO film. (C) 2018 Elsevier Ltd. All rights reserved.