Optical properties of highly oriented nanostructured CuI (111) thin films

Transparent nanostructured copper(I) iodide (CuI) thin films of varying thicknesses were deposited by thermal evaporation of pre-melt quenched CuI powders and their structural and optical properties are reported. X-ray diffraction characterization identifies y-CuI and suggests that the films are monocrystalline in nature showing high crystallographic orientation along CuI (111). SEM studies reveal spherical granules growing in size with increasing film thickness. Thinner films were characterised by high dislocation densities. Optical studies revealed a red shift in the absorption edge and decreased optical band gap energies with film thickness.