Alternative approaches to random texturing to improve light coupling into solar cells are plentiful, and the understanding of dedicated photonic structures for this purpose deepens continuously. However, only few of the proposed designs are adopted by the PV industry due to lack of scalability. Here, we propose a disordered, nanophotonic ARC design based on cylinder-shaped scattering elements made of titanium dioxide that can be applied to practically any device, irrespective of its material or surface topography. Fabrication is based on a scalable bottom-up technique using colloidal self-assembly and industrial type heterojunction silicon solar cells of multiple square centimeter area are used as a platform to demonstrate feasibility. We experimentally show a broadband reduction of reflectance leading to a 5.1 %rel improvement of short-circuit compared to a reference cell with an optimized flat ARC (80 nm ITO). We use a theoretical model based on Born's first approximation to link the current increase to the arrangement of disks that is characterized by the structure factor S(q) of the disk array. The performance of our metasurface is also discussed within the framework of helicity preservation, which can be achieved at specific wavelengths for an isolated disk for illumination along the symmetry axis by tuning its dimensions, and in comparison to a simulated periodic metasurface.
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