Preparation of periodically arranged metallic nanostructures using nanoimprint lithography

We present a process chain to generate periodically arranged metallic nanostructures supporting plasmons for the use in solar cells. As proof-of-concept, platinum and silver nanoparticles with a period of 1 m and a diameter of 600 nm were fabricated. For the platinum particles, an absorption enhancement for light with a wavelength of 3.6 m was observed in silicon. By decreasing structure sizes the active spectral region can be shifted to wavelength relevant for solar cell applications. Therefore, in a second step a silver grating with a smaller period and also smaller diameter of approximately 200 nm was realized