Thin film science has received tremendous attention in last five-six decades especially after the World war II, because of numerous and widespread applications of thin films in electronic industries, micro-electronics and hybrid circuits, optical devices, sensors, superconductivity and recently high memory computer elements etc. Due to the potential applications, thin films of Indium doped CuSe have been extensively studied by doping N or P-type semiconducting material, so that they may be used in various solid state devices. From the present studies it is seen that there are great potentiality to prepare solar cell and barrier junctions with Cu1-xInxSe by thermal evaporation method by improving their diode quality after proper doping, annealing, reduction of interfacial layer and passivation of surface states etc. As the world moves towards realization of high efficiency photovoltaic cells, the race for intermediate defect band materials is on. Doping and nano technology are in the race to establish them as key to manufacturing such materials.