Simulation and numerical modeling of high‐efficiency CZTS solar cells with a BSF layer

The present paper deals with the photovoltaic performance‐based numerical evaluation of copper–zinc–tin–sulfur (CZTS) solar cells embedded with CZTSe as a back surface field (BSF) layer. CZTS has been considered a leading candidate for the fabrication of solar devices owing to its availability and absence of toxicity. Adding a BSF layer to a solar device is a novel way to boost efficiency. It reduces the recombination of the carriers at the back surface, thus increasing the overall current output of the solar cells. SCAPS 1D simulator is used to study the impact of several parameters on electrical properties like temperature, the thickness of the CZTS layer, acceptor doping concentration, and the impact of series and shunt resistances. Considering the optimized parameters in each layer of the solar cells, this work delivers 24.7% efficiency with the BSF layer, which is 8% more than that without the BSF layer. The results of this modeling will facilitate researchers to fabricate a highly efficient CZTS solar cell.