Preparation and Characterization of CuInS2 Thin Films by Sulfurization Process

Abstract

AbstractI–III–VI2 groups of ternary chalcopyrite semiconductors have attracted much interest in recent years because of their potential applications in the field of light-emitting diodes, photovoltaic detectors, non-linear optics1 and solar cells. Ternary compound CuInS2 semiconductor is one of these compounds, due to a superior band-gap of about 1.5eV, matching almost ideally to the solar spectrum, CuInS2 has in principle the highest conversion efficiency among the Cu-chalcopyrite-based solar cells. The Cu-In precursors were grown by magnetron impulse sputtering process. Polycrystalline CuInS2 (CIS) films were prepared by sulfurization of the Cu-In precursors in sulfur atmosphere. The influence of S source temperature and substrate temperature on the film properties was studied respectively. The morphology, microstructure and composition of the films were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). The results explicitly reveal that substrate temperature plays a critical role on the property of the CuInS2 films during the sulfurization process. As the increasing of the temperature, the performance of the films improve gradually, when sulfurization temperature at 550°C and S source temperature at 350°C, the performance of the film is the best.KeywordsCuInS2 thin films chalcopyrite Sulfurization Solar Cell