Some physical properties of Sn-doped CdO thin films prepared by chemical bath deposition

Undoped and Sn-doped CdO thin films were prepared by the chemical bath deposition method by means of a procedure that improves the deposition efficiency. All as-grown films were crystallized in the cubic structure of cadmium peroxide (CdO2) and transformed into CdO with a cubic structure after an annealing process. The as-grown films have a high resistivity (> 10(6) Omega cm) and an optical bandgap around 3.6 eV Undoped CdO displays an optical bandgap around 2.32-2.54 eV and has an electrical conductivity of g x 10(-4) Omega cm. The Sn incorporation into CdO produces a blue shift in the optical bandgap (from 2.55 to 2.84 eV) and a decrease in the electrical conductivity. The deposition procedure described here gives colloid-free surface thin films as indicated by the surface morphology analysis. (c) 2006 Elsevier B.V. All rights reserved.