Licensed Under Creative Commons Attribution CC BY Effect of Zinc Doping on Cdo Thin Films Prepared

Abstract: Pure (undoped) and Zinc doped CdO thin films were prepared using spray pyrolysis technique with various dopant concentrations of Zn such as 3, 5, 7, 10 and 15 % on glass substrates. Influence of Zn doping on the structural, optical and electrical properties of CdO thin films is reported. XRD analysis reveals that as prepared pure and Zn doped CdO films show polycrystalline nature with face centered cubic structure. Also, Zn doping significantly increases the crystallinity and changes the crystallite size. SEM images shows grains which are uniform and agglomerated grain size increasing with increase in dopant concentration. The transmittance of the prepared CdO films recorded in the UV visible spectra show 50 to 70 % in the visible region. However, the higher dopant concentration of Zn (10 and 15%) in CdO diminishes the transmittance value. The estimated optical bandgap varies from 2.59 to 2.65 eV for various dopant concentrations. Hall measurement shows that the films are n-type semiconductor. Also, it is observed that when the doping level is increased, the electrical resistivity also increases in the spray pyrolysed CdO thin film