Conference Paper

Surface Plasmon Enhancement of Optical Absorption of Thin Film a-Si:H Solar Cells with Metallic Nanoparticles

DOI: 10.1109/PVSC.2009.5411623 Conference: 34th IEEE PVSC Proceedings

ABSTRACT We design and fabricate a-Si:H solar cells with plasmonic crystal back reflectors demonstrating enhanced absorption of near infrared photons. Rigorous simulations predict plasmonic nanoparticles on ITO can increase absorption in the near infrared. Rigorous simulations also predict plasmonic crystal back reflectors with a pitch of ~750 nm to optimize the enhanced absorption. Such periodic back reflectors have been fabricated with photo-lithography and a-Si:H solar cells have been grown on them by PECVD. The solar cells display ~9% improvement in short circuit current and external quantum efficiency and a absorption enhancement factor exceeding 8 above 650 nm.

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