Cadmium sulphide polycrystalline thin films were deposited under potentiostatic control on indium tin oxide (ITO) coated glass substrate from an acidic solution containing cadmium chloride and sodium thiosulphate. Voltammograms were recorded to determine the optimal potential region for the co-deposition of CdS. The deposition was carried out for various cathodic potentials and bath temperatures. The structural, morphological, compositional, and optical properties of the films have been investigated. XRD patterns show that the films deposited at room bath temperature are amorphous, whereas those deposited at higher temperature are crystallized in the hexagonal structure. The thermal annealing of the deposits at T = 400 °C for 10 min in air improves the crystallinity and decreases the band gap value from 2.52 to 2.4 eV. EDAX analysis of CdS films deposited at E = -640 mV vs. SCE reveals a ratio of Cd/S close to unity. Different stages of CdS growth on ITO substrates were observed ex-situ by atomic force microscopy (AFM). The electrodeposition of CdS films has been observed to occur in two stages: laterally along the substrate plane, then perpendicularly in the normal plane. Complete conformal coverage was observed at low thickness values.
|Number of pages||11|
|Journal||Physica Status Solidi (A) Applied Research|
|Publication status||Published - Mar 1999|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics