FWHM and Sensitivity Study of Bimetallic SPR Sensor Chip

A study of surface plasmon resonance (SPR) using bimetallic sensor chips with the help of a custom made and low cost portable device is presented in this paper. Pulsed DC magnetron sputtered bimetallic films of gold over silver were used in the construction of SPR sensor chip. The measurements of the deposited metal film thicknesses were done using X-Ray Reflectivity (XRR) method. The performance characteristics of the silver, gold and bimetallic sensor chips were investigated emphasizing on parameters such as improved full width at half maxima (FWHM) and sensitivity against standard solutions of known refractive index. The bimetallic film with the thickness of silver 35nm and gold 15nm accounted for a stable, sensitive and accurate sensing of Surface Plasmon Resonance.