Sulfurization growth of single-phase chalcopyrite CuInS2 (CIS) thin films was demonstrated using less hazardous liquid metal-organic ditertiarybutylsulfide [( t-C4H9)(2)S: DTBS]. The effect of sulfurization temperature and DTBS flow rate on the structural and optical properties of CIS was analyzed by scanning electron microscope, X-ray diffraction, energy dispersive X-ray spectroscopy, and photoluminescence spectra. The measurement results indicated that the CIS film formed by this method was suitable as a photo-absorbing layer for CIS-based solar cells. (C) 2014 Elsevier B. V. All rights reserved.