In this study, we proposed a Cd-free Cu (In,Ga)Se2 (CIGS)-based solar cell with low-cost and high performance. This is achieved by using lead sulfide (PbS) as an electron back reflector and zinc sulfide (ZnS) as a buffer layer instead of cadmium sulfide (CdS) layer. 1D-solar cell capacitance simulator (SCAPS) was employed to optimize our proposed structure of Al-ZnO/ZnS/CIGS/PbS/Mo by investigating the effect of varying thicknesses and doping concentrations of CIGS absorber layer and ZnS buffer layer. Moreover, the effect of operating temperature on the performance of this structure was investigated. The results of the simulation of J-V characteristics showed that the efficiency of the proposed structure at 300 K is 25.5% with a 0.9 μm thickness and acceptor concentration of 1017 cm-3 for CIGS layer and 0.03 μm thickness and donor concentration of 3×1017 cm-3 ZnS layers, respectively. The proposed work improves the efficiency; in addition, the thickness of CIGS layer decreases significantly. |
