MORPHOLOGICAL CHARACTERIZATION AND XPS STUDIES OF AgInS2 THIN FILMS FOR SOLAR CELLS APPLICATIONS

This work presents results related to the morphological characterization, the phase identification and study of the oxidation states of AgInS2 thin films grown using a procedure based on the sequential evaporation of metallic precursors in presence of elemental sulphur, in a two stage process. Effects of the substrate temperature and evaporated mass of Ag to evaporated mass of In (m(Ag)/m(In)) ratio on the phase, crystalline structure and homogeneity in the chemical composition were studied through Atomic Force Microscope (AFM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements. It was found that the deposition conditions affect the morphology and the homogeneity of the chemical composition of the AgInS2 films, as well as the phase in which these films grow. Moreover, conditions were found to prepare thin films containing only the AgInS2 phase, grown with tetragonal chalcopyrite type structure and good homogeneity of chemical composition in the whole volume. The deposited AgInS2 films demonstrated to have good properties for its use as absorber layers in thin film solar cells.