Fabrication of SERS Active Substrates by Nanoimprint Lithography

摘要

A method for low-cost and high throughput fabrication of SERS substrates based on nanoimprint lithography (NIL) has been developed. The SERS effect for detection of rhodamine 6G (R6G) molecules is demonstrated on two model nanostructures comprising either Au nano-crescents or Ag nano-wells fabricated. Numerical simulations based on discrete dipole approximation (DDA) show that the observed enhancement of the SERS signal for the given geometries originates from hot-spots localized at the tips of the nanocrescent. For the nanowell, the hotspots are mainly localized inside the cavity, on the side of the nanodonut and at the edge of the bottom nanodisc when it is excited by a laser at the wavelength of 785 nm.