“…This material possesses several advantages over CuInSe 2 , namely a band gap energy (1.5 eV) that closely matches the visible part of the solar spectrum, a higher absorption coefficient (10 5 cm À1 ) and a lower toxicity. CuInS 2 thin films had been studied intensively by physical and chemical methods, such as co-evaporation [6], molecular beam deposition [7], ion plating [8], chemical vapour deposition [9], spray pyrolysis [10], chemical bath deposition [11], electro-deposition [12]. However, these methods are usually complex and expensive due to rigorous synthetic conditions such as the need for a high vacuum and temperature.…”