Numerical simulations on CZTS/CZTSe based solar cell with ZnSe as an alternative buffer layer using SCAPS-1D

Abstract In CZTS based solar cells, there have been intensive research to replace the toxic CdS buffer layer with alternative materials. In this paper, we proposed and simulated structure of CZTS/CZTSe based Solar Cell Al-ZnO/i-ZnO/ZnSe/Absorber/Mo with ZnSe as a buffer layer using SCAPS-1D simulator. Further, we have investigated the same structure employing different absorber layers such as CZTS, CZTSe and stacking of CZTS and CZTSe sequentially. The optimization of solar cell device is carried out and efficiency found to be 16.24%, 19.59% and 21.17% where the thickness of the absorber layer is 1.5 µm, 1 µm, 2.5 µm and 1 µm, respectively, for CZTS, CZTSe and stacking of CZTS and CZTSe. The calculated values of efficiency (η), fill factor (FF), open circuit voltage (Voc) and current density (Jsc) are compared with the data available in literature with CdS as the buffer layer.