FDTD based Plasmonic Light Trapping Analysis in Thin Film Hydrogenated Amorphous Silicon Solar Cells

Abstract

For thin film solar cells, plasmonics is a novel light trapping technique based on light scattering due to metal nanoparticles through excitation of localized surface plasmons. The excited surface plasmon at the interface of a higher dielectric active semiconducting layer and the metal, by channelling incident radiations will trap light within the device for the higher optical path in physically thin structures resulting in enhanced photocurrent. In this paper, through FDTD based electromagnetic simulations, significance of controlled nanopatterning of silver (Ag) on the front side of p-i-n hydrogenated amorphous silicon for light absorption in the devices is analyzed. The analysis includes better control of nanoparticle parameters like size, shape, distribution and spacing for obtaining full benefits of plasmonic effects. It is demonstrated with an attractive strategy of fine tuning the nanostructures, incident light coupling with semiconductor ensures light confinement within the active layer promoting photon absorption across visible and near infrared regions.