Optimization of absorption layer and back reflection layer thicknesses for enhanced solar cell efficiency

This study investigated the impact of absorption layer thickness and back reflection layer incorporation on (CIGS/TiO2/ZTO/ZnO:Al) solar cell efficiency. Results demonstrated that cell efficiency increases with absorption layer thickness until stabilizing at an optimal balance with other layers. The addition of a back reflection layer enhanced the efficiency while allowing for reduced absorption layer thickness, potentially lowering production costs. MoSe₂ was identified as the optimal back reflection layer material, enabling a reduction in absorption layer thickness to 0.5 µm. Initial results yielded Voc = 0.6865 V, Jsc=40.32 mA/cm², FF = 83.30 %, and η = 23.06 %. Further investigation revealed that back reflection layer thickness also influences cell performance, with efficiency increasing until stabilization. Optimizing this parameter resulted in improved final outcomes: Voc=0.6955 V, Jsc=42.98 mA/cm², FF = 83.10 % and η = 24.84 %. These findings contribute to the ongoing efforts to enhance solar cell efficiency and reduce manufacturing costs.