Structural, optical and electrical properties of Mg-doped CuCrO2 thin films by sol-gel processing

CuCr(1-x)MgxO(2) (x = 0, 0.03, 0.05, 0.07) thin films were prepared on sapphire substrates by sol-gel processing. The effect of Mg concentrations on the structural, morphological, electrical and optical properties was investigated. Highly transparent >= 70% Mg-doped CuCrO2 thin films with p-type conduction and semiconductor behavior were obtained. The microstructure of the systems was characterized by scanning electron microscopy and the roughness increased as the content of Mg increased. The photoluminescence spectra results indicated that it had a green luminescent emission peak at the 530 nm. In this paper, CuCr0.95Mg0.05O2 film has the lowest resistivity of 7.34 Omega cm with direct band gap of 3.11 eV. In order to investigate the conduction mechanism, the energy band of the CuCrO2 films is constructed based on the grain-boundary scattering. (C) 2011 Elsevier B.V. All rights reserved.