Fabrication of long-range surface plasmon-polariton Bragg gratings with microfluidic channels in Cytop claddings

The fabrication of a novel plasmonic Bragg grating, consisting of a gold stripe lithographically stepped in width to form a waveguide Bragg grating, embedded in Cytop claddings, with an etched fluidic channel is described. The structure is designed and fabricated to be used as a compact biosensor excited via butt-coupling to an optical fibre carrying TM-polarized light. Fabrication includes Cytop bottom and top claddings, a stepped-in-width gold stripe defined by optical contact lithography, metal evaporation and lift-off, and fluidic channels etched into the top cladding via an anisotropic radical ion beam. Completed devices are presented along with preliminary optical measurements. (C) 2015 Elsevier B.V. All rights reserved.