Fabrication of Long Range Surface Plasmon Polariton Bragg Waveguide Biosensors on Cytop and Multilayer Substrates

This thesis documents the micro-fabrication of a Long Range Surface Plasmon Polariton (LRSPP) biosensor device design that incorporates Bragg grating waveguides. The majority of the work involved the fine tuning of the bi-layer lithography, ultra-violet (UV) exposure and metal deposition micro-fabrication procedures. The goal was to resolve very fine features, accurately produce thin metallization and achieve a high quality metal surface. Repeatable resolution of Bragg gratings having a step-in-width from 8µm to 2µm, a 50% duty cycle and a period of 1690nm to 1800nm, was achieved with bi-layer lithography and UV exposure. A gold thickness of 35nm±5% and surface roughness of better than 2nm rms and average was achieved using thermal vacuum chamber deposition. The fabrication was performed on two different substrates; Cytop and a prefabricated Ta2O5/SiO2 multilayer stack.