This study investigates the effects of co-doping ZnO thin films with aluminum (Al) and boron (B) on their optical properties for enhanced solar cell efficiency. Using the Sol-gel synthesis process, we deposited ZnO thin films with varying Al and B precursor concentrations (1-4 wt%) on glass substrate via dip-coating. UV-visible and photoluminescence (PL) spectroscopy characterized the films' optical characteristics. The results show that co-doped ZnO films exhibit high transparency (up to 91%) and tunable band gaps (3.1-3.48 eV). Notably, the PL intensity (1.094) is significantly enhanced compared to singly doped ZnO:Al and ZnO:B, indicating optimized charge carrier dynamics. These findings demonstrate the potential of Al and B co-doped ZnO thin films for improved solar cell performance.

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