Impact of doping concentration, thickness, and band-gap on individual layer efficiency of CIGS solar cell

An investigation with the individual layer physical property of the CIGS solar cells is a significant parameter to design and fabricate highly efficient devices. Therefore, this work demonstrates the thickness and carrier concentrations doping dependence simulations using SCAPS 1D software. The optimized CIGS solar cells different layer properties such as short-circuit current density (Jsc), open-circuit voltage (Voc), Fill Factor (FF) and conversion efficiency with varying thickness and doped concentration are presented. This optimized layer by layer simulation work would be useful to build a suitable CIGS solar cell structure. This simulation investigation showed that an optimal CIGS device structure can be fabricated possessing the configuration of a window layer ZnO: Al thickness 0.02 μm, ZnO layer thickness 0.01 μ m with ND = 1021 cm-3 and ND = 1019 cm-3, a CdS buffer layer thickness 0.01 μm with ND = 1019 cm-3 and absorber layer CIGS in the thickness range of 1-4 μm with the doping level range NA = 1013-1016 cm-3, along with the optimal CIGS energy bandgap range of 1.3-1.45 eV. According to optimized simulation results, a CIGS solar cell device can possess electric efficiency 26.61%, FF 82.96%, current density of 38.21 mA/cm2 with the open circuit voltage 0.7977 eV. Hence, these optimized simulation findings could be helpful to provide a path to design and fabricate highly efficient CIGS solar cells devices.