Optimizing ZnO/CdS/CdTe bilayer structures for enhanced CdTe solar cell efficiency: A machine learning approach

In the pursuit of enhancing solar cell efficiency, optimizing multiple parameters remains a significant challenge. Our simulation-based study aimed to identify the optimal thickness combination for ZnO/CdS/CdTe solar cells. Through meticulous analysis of experimental optical absorbance data and electrical properties, we discovered that thicker CdS layers, despite being a compatible partner for CdTe, led to efficiency reduction due to high optical absorbance. In contrast, a ZnO/CdS bilayer window with a 250 nm/50 nm thickness combination demonstrated superior efficiency owing to ZnO’s higher bandgap and lower absorbance. Moreover, our investigation concluded that a 2.5 \(\mu\) $\mu$ m thick CdTe absorber layer is sufficient for effective conversion, yielding a remarkable 17.66% efficiency with a 73.7% fill factor. These findings offer valuable insights into optimizing solar cell components, paving the way for improved designs with enhanced conversion efficiencies.