In the present study we report the electrodeposition and characterization of CIS and CIGS thin films and a post-deposition thermal processing in vacuum to improve the film stoichiometry by incorporating additional In, Ga and Se. Different kinds of analyses showed that CIS as well as CIGS possess a very thin In-rich surface n-layer. The formation and characterization of solar cell structures from the electrodeposited precursor with the configuratio n glass/Cr/Mo/CIS(CIGS)/CdS/ZnO/MgF2 is also reported. The optoelectronic properties such as Voc, Isc, FF, eta etc, of the cells are presented.