Properties of spray deposited Zn, Mg incorporated CdO thin films

Undoped CdO film and CdO films which are alloyed with Zn and Mg (ZMCO) at different concentrations were prepared by spray pyrolysis technique using perfume atomizer on glass substrates kept at 400 °C. The effect of Zn, Mg incorporation on the structural, morphological, optical and electrical properties of the CdO films were investigated using X-ray diffraction (XRD), scanning electron microscopy, UV–Vis spectroscopy and dc electrical measurements respectively. XRD analysis showed that all the alloyed films exhibit polycrystalline nature having cubic crystal structure with a (1 1 1) preferential orientation similar to that of the undoped sample. All the Zn, Mg incorporated CdO films have good transparency in the visible region. Optical band gap is blue shifted with increasing Zn, Mg concentration. Electrical studies showed that the ZMCO film coated with 6 at.% Zn, Mg concentration exhibit a minimum resistivity of 0.724 × 10⁻⁴ Ω-cm. The high transparency, widened band gap energy and improved electrical properties obtained infer that ZMCO thin films find applications in optoelectronic devices, especially in solar cells.