Solar cells have high potential as an alternative energy technology for fulfilling the energy needs. It has the additional advantage being environmentally friendly. Solar photovoltaic cells based on single crystalline Si are prohibitively expensive. Hence, researchers are looking for solar cell materials which are cheap and abundant. Successful thin film solar cells based on CuInGaSe2 uses costly and non-abundant elements like In & Ga, CdTe uses toxic material Cd. To overcome these associated difficulties, we have chosen Cu2ZnSnSe4 thin films which contain elements which are relatively cheap, abundant and less toxic. In this book a brief review of the solar cell absorber layers were presented along with their successes and present market values. Focus is mainly concentrated on the qualities and suitability of Cu2ZnSnSe4 thin films as absorber layers. Preparation (using co-evaporation)and characterization details of this materials are highlighted. Parameters like optimum deposition conditions and ratio between elements re given. Brief description of window preparation and characterization is also presented along with the scope for future work to encourage the readers.