Cu₂BaSnS₄/Cu₂FeSnS₄ combination for a good light absorption in thin-film solar cells—a numerical model

This research paper consists of a numerical simulation, where we studied the performance of a solar cell with a double-absorber layer. The materials used in this work are similar kesterites based on Cu₂FeSnS₄ (CFTS) and Cu₂BaSnS₄ (CBTS), where CFTS is the main absorber with E_g = 1.5 eV, and CBTS is the extra absorber with E_g = 1.9 eV. The use of both materials to absorb light in the proposed solar cell was very beneficial for photovoltaic performance. The study was mainly done on the different parameters and properties of the solar cell, such as thicknesses, concentrations of doping, and resistances. As a result, the proposed structure has great outputs. It offers 1.48 V, 28.26 mA/cm², 82.68, and 34.65% for V_oc, J_sc, FF, and ƞ, respectively.