Precursor aging effect on the properties of CdZnS films

Abstract

Nanostructured ternary Zn-doped CdS (CdZnS) thin films were fabricated from fresh and aged (1, 2, 3 and 4 days) starting solutions by the spray pyrolysis technique using a perfume atomizer. X-ray diffraction studies showed that the films are polycrystalline in nature exhibiting hexagonal crystal structure with a (0 0 2) preferential orientation. SEM images showed that the film prepared from 1 day aged solution possesses randomly oriented CdS crystallites of elongated needle shape. The optical band gap values exhibit a red shift with aging time of the precursor solution. A minimum resistivity of 3.94 × 10⁻³ Ω cm is obtained for the film prepared from 1 day aged solution. The obtained results infer that the CdZnS film prepared from 1 day aged solution exhibits better physical properties.

Keywords:

• Thin films
• X-ray diffraction
• Optical band gap
• Electrical resistivity

Acknowledgements

The authors are thankful to Head and Mr Karthik, Alagappa University for the XRD measurements.