Abstract
In this work, the characteristics of 5 wt% Cu doped ZnO thin films deposited by sol gel on glass substrates were studied. The objective of the present work is to study the influence of different annealing temperatures on the structural, morphological and optical properties of 5 wt% Cu doped ZnO thin films. For this purpose we have used XRD, AFM and UV-visible spectroscopy for films characterization. Structural analysis showed that all films are polycrystalline with hexagonal wurtzite structure and preferred orientation (002) which gradually improves with increasing the annealing temperature. The grain size is calculated by the Scherrer method ranges from 21.65 nm to 36.47 nm. The AFM study showed an increase in surface roughness with increasing annealing temperature. Optical characterization in the visible range from 300 to 1100 nm showed that the deposited layers have a high transmission factor (>78%). The calculated gaps vary between 3.28 and 3.36 eV in the whole investigated annealing temperature range. (C) 2014 Elsevier Ltd. All rights reserved.