Structural and optical studies of zinc oxide thin films prepared via sol-gel spin coating method

Abstract

Zinc oxide (ZnO), a wide bandgap (3.37 eV) semiconductor with high exciton binding energy (60 meV), has a wide range of applications in solar cells, sensors, optoelectronic devices, and surface acoustic waveguides, etc. We have used sol-gel spin coating method to prepare ZnO films on glass plate and report the optical and structural properties of the prepared films. ZnO sol was synthesized by dissolving zinc acetatedehydrate in isopropanol alcohol, and then adding diethanolamine. The films coated glass substrate were preheated at 1000C for 10 min and annealed at 4000C for 1 h in air ambience and X-ray diffraction (XRD) analysis reveals hexagonal wurtzite crystal structure. The grain size of the films was calculated using the Scherrer formula. Optical band gap were obtained from uv-visible absorption spectroscopy.