Tin-incorporated nanostructured copper indium oxide delafossite thin films: Structural, electrical and optical analysis

Single phase polycrystalline Sn-doped CuInO2 thin films are prepared by the oxygen plasma enhanced reactive evaporation method. X-ray diffraction indicates a preferential orientation of crystallites along the (006) plane on doping while energy dispersive analysis of X-rays and atomic force microscopy are employed to appraise the composition and morphology of the films, respectively. Remarkably, about 2-3 orders of magnitude enhancement in their electrical conductivity than that reported till date is observed. Further, the Sn-doped thin films possess 2-3 orders of magnitude higher carrier concentration (10(18)-10(19)/cm(3)) than undoped films that is associated with a drastic reduction in mobility. Moreover, different conduction mechanisms possible at different temperature regions ranging from around 55 Ke450 K are studied in detail. While the transparency of the films is increased from 43% to 85% on doping, the optical band gap decreases from 3.83 eV to 3.5 eV. (c) 2018 Elsevier B.V. All rights reserved.