Influence of Deposition Time on the Microstructure and Transport Properties of CdO Thin Films Prepared by Chemical Bath Deposition

P. Perumal, A. Gowri Manohari, Santiyagu Valanarasu, Adaikalam Kathalingam, Jin-Koo Rhee, Narayanan Soundaram, Rathinam Chandramohan

Millimeter-Wave Innovation Technology Research Center (MINT), Dongguk University, Seoul, Korea (South).
Physics Department, Alagappa Government Arts College, Karaikudi, India.
Physics Department, Sree Sevugan Annamalai College, Devakottai, India..

DOI: 10.4236/jsemat.2012.22013                

Abstract

Transparent thin films of CdO has been deposited on to glass substrates employing chemical bath deposition. The prepared films are reproducible, adherent to the substrate, pinhole free and uniform. Amongst the different process parameters, the deposition time plays a significant role in obtaining device quality transparent CdO thin films. X-ray powder diffraction (XRD) studies indicated that the thin films are polycrystalline in nature with cubic phase with a cell constant of a = 4.638 ?. The surface morphology of the prepared CdO thin films was examined by scanning electron microscopy. The films deposited at 24 hrs exhibited highest optical transmittivity (>80%) and the direct band gap energy was found to vary from 2.50 to 2.91 eV with a rise deposition time from 6 to 30 hrs. The electrical resitivity variations of these films were measured in the temperature range between 30?C and 150?C by four-probe technique.

Keywords

Cadmium Oxide; Chemical Bath Deposition; Transparent Electrode

Conflicts of Interest

The authors declare no conflicts of interest.

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