Effect of Concentration on the Optical and Solid State Properties of ZnO Thin Films Deposited by Aqueous Chemical Growth (ACG) Method

S. L. Mammah, F. E. Opara, F. B. Sigalo, S. C. Ezugwu, F. I. Ezema

Department of Physics and Astronomy, University of Nigeria, Nsukka, Nigeria.
Department of Physics, Faculty of Science, Rivers State University of Science and Technology, Port Harcourt, Nigeria.
Department of Science Laboratory Technology, School of Applied Sciences, Rivers State Polytechnic, Bori, Nigeria.

DOI: 10.4236/jmp.2012.39124                

Abstract

Thin films of Zinc Oxide (ZnO) having different concentrations were deposited using the Aqueous Chemical Growth (ACG) method. The films were characterized using Rutherford Back Scattering (RBS) spectroscopy for chemical composition and thickness, X-Ray Diffraction (XRD) for crystallographic structure, a UV-VIS spectrophotometer for the analysis of the optical and solid state properties which include spectral absorbance, transmittance, reflectance, refractive index, direct band gap, real and imaginary dielectric constants, absorption and extinction coefficients and a photomicroscope for photomicrographs. The average deposited film thickness was 100 nm. The results indicate that the values of all the optical and solid state properties investigated vary directly with concentration except transmittance which is the reverse. Thus, the optical and solid state properties of ZnO thin film deposited by the Acqueous Chemical Growth method can be tuned by deliberately controlling the concentration of the precursors for various optoelectronic applications including its application as absorber layer in solar cells.

Keywords

Component; Formatting; Style; Styling; Insert

Conflicts of Interest

The authors declare no conflicts of interest.

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