Diminished Angular Dependency of Crystalline Silicon Microwire Solar Cells Through Broadband Antireflection Using Transparent Spheres

Efficiently capturing incident light while minimizing surface reflection is the first step to ensuring high power conversion efficiency (PCE) in solar cells. However, since the position of the sun changes depending on the season and time of day, the light absorption of the solar cell is not constant. The amount of light absorbed by a solar cell decreases as the angle of incidence of light increases. Therefore, it is necessary to minimize the light absorption loss induced by the increase in the angle of light incidence to maximize solar power generation. In this study, we employed microwire structures not only to maximize light absorption but also to minimize light absorption loss according to the angle of light incidence. Additionally, we added transparent light-scattering silica beads between the microwires to further minimize light absorption loss according to the angle of incidence of light. As a result, we confirmed that the PCE of the solar cell without the structure decreased by over 55% when the incident angle of light changed from 0 to 60°, whereas the PCE of the solar cells with microwires and silica beads in between decreased by less than 35%. This work provides a novel strategy to reduce the angular dependence of PCE degradation of the solar cells.