Comparative simulation analysis of µc Si:H and SnS BSF layers in CIGS solar cells

Abstract

In this paper, we presented Cu(In1-xGax)Se2 (CIGS) based solar cells in which hydrogenated microcrystalline silicon (µc Si:H) and tin sulfide (SnS) are used as back surface field (BSF) layer. The drawback of CIGS lies in its incorporation of indium (In) and gallium (Ga), both are scarce and expensive materials. Optimizing absorber thickness offers a means to diminish the usage of these materials in the CIGS cells. Integrating a heavily doped layer between the absorber layer and the back surface layer, known as BSF layer, is a successful strategy for minimizing the thickness of the absorber layer. The suggested configuration utilizes µc-Si:H and SnS as the BSF layer. The buffer layer in this configuration employs less harmful InP instead of the typically utilized CdS layer, which contains highly toxic cadmium. All the simulation work is performed using SCAP-1D simulation tool. The utilization of µc Si:H and SnS BSF layers yields optimized efficiencies of 31.51% and 31.01%, respectively. This simulation work demonstrates that use of a proper BSF layer is very effective not only in performance enhancement but also in reducing absorber material thickness.