Photoluminescence enhancement towards high efficiency plasmonic solar cells

We demonstrate enhanced absorption in silicon wafers when plasmonic nanoparticles are added to a conventional rear contact structure. A rear side light trapping with plasmonic nanoparticles and various thicknesses of Si₃N₄ layer is studied and compared to a structure with combined plasmonics and diffused paint. Photoluminescence is applied to extract the absorptivity in order to exclude free carrier and parasitic absorption. Modeling shows that the absorption within a cell structure with plasmonic nanoparticles and optimum capping layer is expected to be enhanced by 53% of value for an ideal Lambertian reflector.