A Comparative Numerical Modeling of High‐Efficient CBTS Solar Cell Using SCAPS‐1D

ABSTRACT

Copper barium tin sulfide (CBTS), a quaternary semiconductor compound, have attracted immense research interests presently for the fabrication of high efficient and low‐cost thin film solar cell due to its non‐toxic, easily available in earth's crust constituents and unique optical and electrical features. In this work, solar cell capacitance simulator (SCAPS‐1D) has been employed to numerically model, optimize and compare CBTS‐based solar cell with heterojunctions CBTS/CdS, CBTS/SnS ₂ and CBTS/Cd _0.1 Zn _0.9 S with a view to obtain a suitable substitute for toxic cadmium sulfide (CdS). The impact of thickness, bulk and interface defect density of the absorber and buffer layer, temperature, resistance and back contact work function on the electrical parameters of CBTS based solar cell is analyzed with three different buffer materials such as CdS, tin sulfide (SnS ₂ ) and cadmium zinc sulfide (Cd _0.1 Zn _0.9 S). The optimum absorber and buffer layer thickness obtained is 2.5 and 0.1 µm, respectively. The highest efficiency achieved is 18.42%, 21.51%, and 21.6% for optimized CBTS/CdS/FTO, CBTS/SnS ₂ /FTO, and CBTS/Cd _0.1 Zn _0.9 S/FTO solar cell, respectively. The results prove that low‐toxic Cd _0.1 Zn _0.9 S buffer layer provides best performance among all three buffer layers and non‐toxic SnS ₂ buffer layer also shows promising results.