Structural and optical properties of chemically synthesized monodispersed CdCr2S4 films

Abstract

Alkaline chemical synthesis of amorphous CdCr2S4 (CCS) thin films of different thicknesses using cadmium chloride, chromic acid, disodium salt of ethylenediaminetetra acetic acid and thiourea precursors is reported, and the structural and surface morphological properties of CCS using X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM) techniques are discussed. Films of aggregated grains with some void spaces are obtained. Change in band gap energy and electrical resistivity of CCS films are discussed as a function of film thickness. n-type conductivity is confirmed from the sign of thermally generated voltage across the cold and hot junctions. (C) 2008 Elsevier Ltd. All rights reserved.