Numerical Investigation of Back Surface Field Optimization in Lead‐Free MAFASnBrI 3 Perovskite Solar Cells for Enhanced Efficiency
Md. Faruk Hossain, Md Masum Mia, Mohammed M. Fadhali, Aijaz Rasool Chaudhry, Ahmad Irfan, Md. Ferdous RahmanABSTRACT
The push for sustainable, non‐toxic solar technologies has driven interest in lead‐free perovskite solar cells (PSCs). This study uses SCAPS‐1D simulations to enhance the performance of MAFASnBrI 3 ‐based PSCs through back surface field (BSF) engineering. Three BSF materials‐Spiro‐OMeTAD, Cu 2 NiSnS 4 (CNTS), and indium telluride (InTe)‐are integrated into a Cu/FTO/CdS/MAFASnBrI 3 /BSF/Au structure to compare their effects on device efficiency. These materials, representing both organic and inorganic hole transport layers, are evaluated for their influence on photovoltaic parameters, quantum efficiency, band alignment, and recombination behavior. Additional parametric studies assess the roles of absorber thickness, doping levels, defect densities, and temperature. All BSF layers enhance charge extraction and suppress recombination at the rear interface, with InTe delivering the best results. Its superior energy level alignment, high hole mobility, and effective passivation yield a peak power conversion efficiency ( PCE ) of 27.97% and stable performance under stress. This work highlights BSF engineering–especially with InTe‐as a key strategy for developing high‐efficiency, thermally stable, lead‐free PSCs, offering valuable insights for future experimental and scalable device design.