Abstract
Hydrogenated amorphous Si ( α-Si:H) is a promising material for photovoltaic applications due to its low cost, high abundance, long lifetime, and non-toxicity. We demonstrate a device designed to investigate the effect of nanostructured back reflectors on quantum efficiency in photovoltaic devices. We adopt a superstrate configuration so that we may use conventional industrial light trapping strategies for thin film solar cells as a reference for comparison. We controlled the nanostructure parameters via a wafer-scale self-assembly technique and systematically studied the relation between nanostructure size and photocurrent generation. The gain/loss transition at short wavelengths showed red-shifts with decreasing nanostructure scale. In the infrared region the nanostructured back reflector shows large photocurrent enhancement with a modified feature scale. This device geometry is a useful archetype for investigating absorption enhancement by nanostructures.
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Hsu, C., Burkhard, G.F., McGehee, M.D. et al. Effects of nanostructured back reflectors on the external quantum efficiency in thin film solar cells. Nano Res. 4, 153–158 (2011). https://doi.org/10.1007/s12274-010-0064-y
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DOI: https://doi.org/10.1007/s12274-010-0064-y