Abstract Deposition of CuInSe 2 thin film on CuGaSe 2 thin film and vice versa has been studied by a low pressure metal–organic chemical vapor deposition technique with three precursors without additional Se. The properties of the resultant films have been examined by scanning electron microscopy, X-ray diffraction, and micro-Raman scattering. Good quality and well demarcated films are obtained only in the case of CuInSe 2 grown on CuGaSe 2 . When CuGaSe 2 was grown on top of CuInSe 2 diffusion of Ga into CuInSe 2 was found to produce an alloy film instead.