Optical and Structural Properties of ZnO Thin Films Fabricated by Sol-Gel Method

Abstract

Highly oriented and transparent ZnO thin films have been fabricated on ultrasonically cleaned quartz substrates by the sol-gel technique. X-ray diffraction, UV-VIS, FTIR, photoluminescence and SEM are used to characterize ZnO thin films. X-ray diffraction study show that all the films prepared in this work have hexagonal wurtzite structure, with lattice constants a = b = 3.260 Å, c = 5.214 Å. The optical band gap energy of the thin films is found to be direct allowed transition ~3.24 eV. The FTIR spectrum of the film has the characteristics ZnO absorption band at 482 cm^?1. The photoluminescence spectrum of the samples has an UV emission peak centred at 383 nm with broad band visible emission centred in the range of 500 - 600 nm.