Journal of Computational Electronics | 2021
A novel design of CTZS/Si tandem solar cell: a numerical approach
Abstract
Multijunction or tandem solar cells can split the solar spectrum over several subcells with different bandgaps to convert sunlight into electricity more effectively than single-junction solar cells. The monolithic tandem design of third\xa0generation silicon solar energy materials is auspicious for photovoltaics. In this paper, the simulation-based studies of copper zinc tin sulfide/silicon (CZTS/Si) tandem cells based on CZTS as an upper subcell and silicon as a lower subcell absorber layer have been performed using SCAPS-1D. This study aims to evaluate the CZTS tandem cells’ performance based on the fact that both subcells are simulated to produce the best efficiency recorded at its bandgap. The simulation and optimization of the single-junction CZTS and Si solar cells were initially performed to fit the state-of-the-art records efficiency of 11.65% and 18.7%, respectively. Further, both the upper and lower cells have been evaluated at different thicknesses for tandem configuration after validation. Also, to obtain the same current for tandem structure, the upper subcell s performance is investigated at different thicknesses ranged from 0.1~1\xa0µm while keeping the lower subcell thickness at 80\xa0µm. Thus, at optimized upper absorber thickness of 0.191\xa0µm and lower subcell 80\xa0µm at transmitted spectrum the same current was obtained and gave an efficiency of 10.6% and 11.9%, respectively. The maximum efficiency of ~\u200923 is obtained for tandem design with enhancing open\xa0circuit voltage 1.4\xa0V.