Optimizing layer configuration and material selection to enhance CIGS solar cell performance through computational simulation

Abstract

The increasing demand for renewable energy has driven research into advanced photovoltaic (PV) technologies for solar cells (SCs). Copper indium gallium selenide (CIGS) SCs present numerous benefits, such as high absorption efficiency, compatibility with flexible substrates, and potential for cost-effective production. This study utilizes SCAPS-1D software to optimize a CIGS-based SC structure featuring a novel Al/ZnO/ZnMnO/CIGS/Cu₂O/Ni configuration. We systematically optimized key parameters, including material selection, layer thickness, doping concentrations, series and shunt resistances, and temperature, to enhance device performance. Our results demonstrate that an optimal configuration with a 3000 nm thick CIGS absorber layer, a 50 nm thick zinc oxide (ZnO) window layer, zinc manganese oxide (ZnMnO) buffer layers, and a 10 nm thick cuprous oxide (Cu₂O) electron-reflecting hole transport layer (ER-HTL) achieves an impressive open-circuit voltage (V_OC) of 1.0112 V, a short-circuit current density (J_SC) of 38.80 mA/cm², a fill factor (FF) of 81.13 %, and a power conversion efficiency (PCE) of 31.84 % under AM1.5G solar spectra. By minimizing series resistance and maximizing shunt resistance, we reduced resistive losses, voltage drop, and current leakage, thus enhancing overall device performance. Additionally, the device exhibited a remarkable quantum efficiency (QE) of approximately 95.54 % within the visible wavelength range. These findings contribute to a deeper understanding of CIGS solar cells and guide future research aimed at optimizing materials and designs to improve efficiency and stability, ultimately advancing affordable solar energy solutions.