Elongated Nanostructured Solar Cells with a Plasmonic Core

In this chapter the effects of the plasmonic response in an elongated nano-scale solar cell with a silver nanoneedle core are explored by measuring photocurrents. The silver nanoneedles formed the support of a conformally grown hydrogenated amorphous silicon (a-Si:H) n-i-p junction around it. A spherical morphology of the solar cell functions as a nano-lens, focusing incoming light directly on the plasmonic silver nanoneedle. We found that plasmonics, geometric optics, and Fresnel reflections affect the nanostructured solar cell performance, depending strongly on light incidence angle and polarization. Besides the plasmonic effects, nano-focusing, and orthogonalization of carrier and photon pathways are simultaneously present at illumination of this structure. In this chapter the photovoltaics characterization techniques and simulations are explained and discussed as well. This work provides valuable insight in solar cell processes in which novel concepts such as plasmonics, elongated nanostructures, and nanolenses are used