Size and Microstructure Effect of Silica Nanosphere Assemblies on Antireflective Capability of Typical Solar Cells

This work addresses the problem of broadband optical scattering by micro-assemblies of submicron silica spherical particles functioning as an antireflective (AR) coating applied to the outer layer of a typical solar cell. Using full-wave electromagnetic simulations based on the finite element method, we conduct numerical investigations of the near-field spatial distribution in the vicinity of such micro-assemblies with different internal microstructures. The assemblies can be either fully ordered or possess a disordered nanotexture formed by the random packing of multiple silica nanospheres (NSs). The primary objective of our research is to evaluate the efficiency of light transmission through the surface layer of a solar cell depending on the structural design of the NS-based AR coating. We show that the minimization of unwanted optical reflection of incident radiation is achieved across the entire spectral range of solar radiation at various angles of incidence by using AR coatings composed of essentially subwavelength NSs arranged in a specific number of ordered (densely packed) or disordered (sparsely packed) consecutive layers, which depends on the substrate optical properties.