Optical properties of extended inverted pyramid arrays enhancing silicon solar cells light absorption, simulated using Comsol Multiphysics®

Surface texturization plays a pivotal role in enhancing the efficiency of silicon solar cells by optimizing light absorption. Macroporous silicon has a versatile manufacturing process, enabling the formation of closely packed pores with surface blades, as reported in previous research. By tweaking etching parameters, tapered pores featuring surface blades can achieve higher aspect ratios, with a geometry similar to that of an extended inverted pyramid. To the best of our knowledge, this specific texturization has not been priorly documented, in the literature. In this study, we employed 3D finite element simulations via the Comsol Multiphysics® Ray Optics module to investigate the optical characteristics of extended inverted pyramids texturization in silicon. Through systematic variations in pore depth, we identified a 35 µm deep pore combined with a surface blade top angle of 9° as optimal for enhanced light absorption, achieving over 95% absorptance across a broad spectrum in the range of 300 nm to 1100 nm for a normal angle of incidence, while maintaining a consistently high absorptance for angles of incidence varying from 0° to 60°. Comparative simulations revealed that the extended inverted pyramid design outperformed other texturizations, showcasing unique light-trapping capabilities and potential to enhance silicon solar cells efficiency, especially in real-world conditions, where light incidence is rarely normal to the surface.