Plasmonic Nanoparticle Films for Solar Cell Applications Fabricated by Size-selective Aerosol Deposition

A soft deposition method for incorporating surface plasmon resonant metal nanoparticles within photovoltaic devices was studied. This self-assembly method provides excellent control over both nanoparticle size and surface coverage. Films of spherical Ag nanoparticles with diameter of ∼100 nm were fabricated by depositing size-selected aerosols on various substrates using electrophoresis. This novel deposition method opens the route to embed plasmonic nanoparticles in the intermediate reflector of a micromorph silicon tandem PV cell. We have for the first time fabricated working tandem cells of this type. Compared to a flat reference device the Ag particles enhanced the short-circuit current density due to improved light trapping. The enhancement is, however, limited by the sulfidation on the surface of Ag nanoparticles and a further optimization of the cell fabrication method is required to prevent a reduction of open-circuit voltage and fill factor.