“…The band gap of the CuIn(S,Se) 2 alloy can be tailored to the optimum band gap value (about 1.4-1.50 eV) for matching the solar spectrum by adjusting the S/(SþSe) ratio. 6 There are a number of film growth technologies to prepare CuIn(S,Se) 2 thin film, such as spray pyrolysis, 7,8 solution growth technique, 9 electrodeposition, [10][11][12] and two-step growth processes. 1,2,6,[13][14][15][16] From the industrial point of view, the two-step sulfurization process may be one of the best methods to prepare CuIn(S,Se) 2 thin films for solar cells.…”