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Copper Indium diselenide and disulphide (CIS) and their alloys with Ga based thin film solar cells have achieved efficiencies approaching 20%. The best results were obtained with chemical bath deposition CdS buffer layers. However, cadmium is harmful for health and environmentally unfriendly. Then, the replacement of toxic CdS buffer layer is a challenge in photovoltaic research development. A variety of alternative Cd-free buffer layers were studied. The most efficient were Zn- and In –based compounds. In this paper, we present some results concerned with high absorbing layers and high transmitting buffer layers prepared by cheap and simple methods. Good quality CIS and CIGS absorber layers prepared by one step electrodeposition. The films were polycristalline and exhibited an optical band gap varying between 1.01 to 1.26 eV by increasing the Ga content in the films. The absorption coefficient is higher than 10⁵ cm^-1. In₂S₃ buffer layers were obtained by flash evaporation. The films exhibited high transmission coefficient, 80-90% and a gap varying between 2.5 and 2.65 eV depending on the thickness and the heat treatments. Finally, In₂S₃/(CIS,CIGS)/Mo/Glass heterostructures has been successfully obtained and has shown a rectifying effect and could be used to low energy production.