Enhanced efficiency of Cu(In,Ga)Se2 solar cells by adding Cu2ZnSn(S,Se)4 absorber layer

A new structure of thin film solar cells, with Cu(In,Ga)Se2 (CIGS) and Cu2ZnSn(S,Se)4 (CZTSSe) as absorber layers, CdS as a buffer layer and ZnO as a window layer, has been simulated using SCAPS one-dimensional simulation program. The aim of the present contribution is to investigate the performance of thin film photovoltaic solar cells. The influences of several factors on the photovoltaic cell parameters are estimated. It is found that by adding CZTSSe as an absorber layer in the conventional CIGS solar cell, the efficiency is enhanced from 17. 91% up to 21.84%, bearing in mind that when only CIGS is used, with the same thickness, we get an efficiency of 19.19%. This result may help in overcoming the problem of the high cost and scarcity of some of the materials, such as indium and gallium used in the production of CIGS solar cells.