Hybrid Design Architecture and Sensitivity Analysis of Cu Based Surface Plasmon Resonance Sensors

Abstract

Surface plasmon resonance (SPR) based optical biosensors have wide-ranging potential for rapid detection in the areas of healthcare, environment, food industry, and biotechnology. Gold and silver are traditionally used for SPR sensors but their drawbacks have led to investigations into alternate plasmonic materials. Our work seeks for an innovative design using SPR-based biosensor design using layers of copper along with other materials like ZnO and graphene for an encapsulating layer, and ZnO and Cr for an interface layer deposited on the glass substrate. We have evaluated various thicknesses and combinations of these layers to identify an optimum design architecture that yields superior performance, which is assessed using a novel performance parameter. Our results show that a 55 nm thick copper sensing layer with a 20 nm thick ZnO interface layer on BK-7 glass substrate, encapsulated with a 5 nm thick ZnO layer leads to the best sensing performance.