Light trapping by plasmonic nanoparticles

Abstract

Metallic nanoparticles sustaining localized surface plasmon resonances (LSPR) are of great interest for enhancing light trapping in thin film photovoltaics. In this chapter, we explore the correlation between structural and optical properties of self-assembled silver nanostructures fabricated by a solid-state dewetting process on various substrates relevant for silicon photovoltaics and later integrated into plasmonic back reflectors (PBRs). Our study allows us to optimize the performance of nanostructures by identifying fabrication conditions in which desirable circular and uniformly spaced nanoparticles are obtained. Second, we introduce a novel optoelectronic spectroscopic method which enables the quantification of absorption enhancement and parasitic losses in thin photovoltaic absorber due to plasmonic light trapping. Finally, we discuss an optimization of plasmon-enhanced thin film silicon solar cells resulting in pronounced broadband enhancement of external quantum efficiency and remarkably high short circuit current densities