Nano-Photonic Structures for Light Trapping in Ultra-Thin Crystalline Silicon Solar Cells
AbstractThick wafer-silicon is the dominant solar cell technology. It is of great interest to develop ultra-thin solar cells that can reduce materials usage, but still achieve acceptable performance and high solar absorption. Accordingly, we developed a highly absorbing ultra-thin crystalline Si based solar cell architecture using periodically patterned front and rear dielectric nanocone arrays which provide enhanced light trapping. The rear nanocones are embedded in a silver back reflector. In contrast to previous approaches, we utilize dielectric photonic crystals with a completely flat silicon absorber layer, providing expected high electronic quality and low carrier recombination. This architecture creates a dense mesh of wave-guided modes at near-infrared wavelengths in the absorber layer, generating enhanced absorption. For thin silicon (<2 μm) and 750 nm pitch arrays, scattering matrix simulations predict enhancements exceeding 90%. Absorption approaches the Lambertian limit at small thicknesses (<10 μm) and is slightly lower (by ~5%) at wafer-scale thicknesses. Parasitic losses are ~25% for ultra-thin (2 μm) silicon and just 1%–2% for thicker (>100 μm) cells. There is potential for 20 μm thick cells to provide 30 mA/cm2 photo-current and >20% efficiency. This architecture has great promise for ultra-thin silicon solar panels with reduced material utilization and enhanced light-trapping. View Full-Text
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Pathi, P.; Peer, A.; Biswas, R. Nano-Photonic Structures for Light Trapping in Ultra-Thin Crystalline Silicon Solar Cells. Nanomaterials 2017, 7, 17.
Pathi P, Peer A, Biswas R. Nano-Photonic Structures for Light Trapping in Ultra-Thin Crystalline Silicon Solar Cells. Nanomaterials. 2017; 7(1):17.Chicago/Turabian Style
Pathi, Prathap; Peer, Akshit; Biswas, Rana. 2017. "Nano-Photonic Structures for Light Trapping in Ultra-Thin Crystalline Silicon Solar Cells." Nanomaterials 7, no. 1: 17.
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