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Silicon nanowires can improve the optical properties of silicon solar cells,but commonly-held concerns about the effects of nanostructuring on device performance have limited their adoption.Here we present experimental results of our design and processing innovations applied to silicon-nanowire solar cells.We confirm not only the excellent anti-reflection and absorption benefits but also demonstrate high minority carrier lifetime and efficiencies >18%.Nanowires enhance the efficiency of crystalline silicon solar cells by reducing reflection over a broad range of incident wavelengths and angles: measured reflection is less than 1% for a weighted average over the solar spectrum.Furthermore,the nanowires increase the optical path length within the device,allowing the absorption of the silicon to approach the Lambertian limit for light trapping.This increased absorption improves efficiency for standard thickness cells (mainly in the infrared),as well as significantly increasing the amount of light absorbed in thin crystalline silicon cells.Our low-cost nanowire fabrication process is independent of crystallographic orientation and overall is especially well-suited for multicrystalline and thin crystalline silicon cells.We will discuss the benefits of integrating nanowires into existing solar cell production lines;nanowires can potentially increase the efficiency by 1% or more absolute and reduce costs by $0.05-0.10/Wp.We will also present how our nanowires enable several manufacturing improvements such as thin wafers,N-type wafers,passivated back contacts and plated front metal contacts to enable further cost and performance advantages with crystalline silicon wafers.