The Trade-Off Performance of Surface Plasmon Resonance Sensing Utilizing Thin Layer Oxide Under the Metal Layer

An analytical study of oxide material layers under thin-film metal in a surface plasmon resonance sensor is investigated for the trade-off adjustment between the sensitivity or dynamic range performance. Thin layer SiO2, TiO2, and TiO2/SiO2 are investigated as the coupling layer in Kretschmann configuration using monochromatic light at 600 nm of wavelength. Two signal acquisition methods, intensity modulation, and angular interrogation were presented and showed a trade-off between the sensitivity slope and the dynamic range. Finally, the SPR sensing layers of TiO2/SiO2/Au using the angular interrogation method performs the significant enhancement for both dynamic range and sensitivity of the sensing.