STRUCTURAL AND OPTICAL PROPERTIES OF UNDOPED AND Co DOPED ZnO NANOSTRUCTURED THIN FILMS
Keywords:
Zinc oxide, sol-gel, dip coating, thin filmAbstract
In this study ZnO:Co nano structured thin films doped with cobalt at different concentrations were deposited on glass substrates by the sol-gel dip coating method. Characterization techniques of XRD, SEM with EDAX, and UV-Visible spectra measurements were done to investigate the effects of the Co doping concentration on the optical and structural properties of the ZnO:Co nanostructured thin films. The XRD patterns of all nano structured films show the crystalline behavior and are of a hexagonal wurtzite structure. Our results reveal that, with a high percent of cobalt, not only the degree of the crystalline behavior but also a broadening of the peak occurs. The compositional analysis was carried out by energy dispersive X-ray (EDX) measurement. The optical studies show that the band gap of ZnO:Co decreases the d electron of the Co atom and bandcarriers of the host material. This unique property of ZnCoO films can be used to fabricate transparent electrodes in flat panel displays and metal-insulator-semiconductor diodes.
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