Experimental and theoretical study of electrodeposited CuInS2 thin films for solar cell applications

Abstract

Absorbent CuInS2 layers were successfully prepared using an electrodeposition technique on ITO-coated glass, followed by a sulfidation process. The effects of sulfurization time on the structural, morphological and optical properties of samples were examined. The structure, morphology, and composition of synthesized films were characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS), while the optical properties were examined by UV-VIS-NIR spectrophotometry. The experimental results show that the resulting films (CIS) are polycrystalline with a chalcopyrite structure with a preferential orientation along the (112) plane and show that Cu atoms separate near the grain boundaries and a wide bandgap value of 1.52 eV. The SEM study showed that the surface of the CIS films was dense and uniform. Theoretical calculations carried out by TB-mBJ showed a wide bandgap of 1.15 eV, a high refractive index, and absorption coefficient in the visible region which is consistent with the experimental results found.