Effect of Zinc Ion Concentration on Structure, Electrical and Optical Properties of ZnO Prepared by CBD

Abstract

Effect of zinc ion concentration of ZnO thin films, prepared by using
chemical bath deposition technique, is discussed. ZnO films were characterized
using different techniques such as X-ray diffraction (XRD), electrical resistivity
measurement, and optical absorption and transmission. The XRD analysis
showed that all the films had a preferred (002) orientation. The ZnO films
showed, on average 20% reflectance, the transmittance range between 35% and
45% for different morality before annealing. Optical band gap decreases with
increasing zinc ion concentration. Linear increase in resistivity with increasing
in molarities was shown. The films were annealed at 473 K and showed
decreases in the reflectance of the films, but transmitting increase to 75% - 80%.
Therefore by annealing process the hydroxide phase converted to the oxide
phase. The annealed samples show a relative decrease in band gap with
annealing.