Effect of Annealing Temperature on Structural, Photoluminescence and Photoconductivity Properties of ZnO Thin Film Deposited on Glass Substrate by Sol-Gel Spin Coating Method

摘要

In this work, zinc oxide (ZnO) thin films have been deposited on glass substrate using a simple and inexpensive multi-step sol-gel spin coating method at annealing temperatures of 300, 400, 500 and 600 degrees C in an open atmosphere. The influence of annealing on structural, photoluminescence and photoconductivity properties of ZnO thin films has been systematically investigated. X-ray diffraction pattern reveals that all ZnO thin films are polycrystalline with hexagonal wurtzite structure. Scanning electron micrograph depicted the formation of ZnO nanofibrous structure. Photoluminescence properties of ZnO thin films have been investigated by photoluminescence spectroscopy at room temperature. Photoconductivity properties have been investigated in terms of several parameters such as voltage dependence of photocurrent and dark current as well as time-resolved rise and decay of photocurrent. The rise and decay spectra under periodic illumination show reproducible and stable photoresponse. The synthesized ZnO thin film seems to be having potential use in UV-Vis photodetectors.