[01] U. S. Mbamara, Department of Physics, Federal University of Technology, Owerri, Nigeria. [02] B. Olofinjana, Department of Physics, Obafemi Awolowo University, Ile-Ife, Nigeria. [03] C. Lorenzo-Martin, Tribology Section, Argonne National Laboratory, Argonne, IL, USA. [04] O. O. Ajayi, Tribology Section, Argonne National Laboratory, Argonne, IL, USA. [05] E. I. Obiajunwa, Centre for Energy Research and Development, Obafemi Awolowo University, Ile-Ife, Nigeria. [06] E. O. B. Ajayi, Department of Physics, Obafemi Awolowo University, Ile-Ife, Nigeria.

The surface statistical properties of ZnO:N thin films deposited by metalorganic chemical vapour deposition (MOCVD) with different precursor dopant mixtures were investigated. The precursor was of single solid-sources, consisting of physical mixtures of zinc acetate and ammonium acetate in four separate ratios of 9:1, 8:2, 7:3 and 6:4 respectively. The examination of the thin films was carried out by Rutherford Backscattering Spectroscopy (RBS), Optical Microscopy and Optical Profilometry techniques. The thin film compositions gave a consistent Zn:O:N stoichiometry of 5:4:1, despite the varied precursor compositions used in preparing them. Their surfaces exhibited properties which are likely to support visible light attenuation in fibre optics, photoconductivity, electron transport, gas sensing and load-bearing capabilities. The key statistical parameters, Ra, Rq, Rt, Rz, Sq/Sa, Ssk and Sku, showed trends with respect to the precursor dopant concentrations. The fractal dimensions calculated also exhibited some trend. The values of Rq/Ra and Sq/Sa closely depicted Gaussian distribution of asperities on the surfaces, with the values also predicting useful applications in tribology.

MOCVD, Zinc Acetate-Ammonium Acetate Precursors, Nitrogen-Doped Zinc Oxide Thin Films, Surface Colours, Surface Topographies

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