Experimental Study of the Optimal Metal Film for Surface Plasmon Resonance

摘要

Surface plasmon resonance (SPR) is an optical sensing technique which is highly sensitive to a slight change of refractive index and is widely used in physical, chemical and biological researches. However, sensitivity of the most commonly used SPR sensors which are based on Kretschmann module, seriously depends on the types and the thicknesses of the metal film in the SPR module. And there is not much experimental research on the relation between the properties of a metal film and the performance of a SPR sensor. In this paper, we prepare metal films with different types and thicknesses using magnetron sputtering method. SPR sensors based on angle interrogation and wavelength interrogation are built and used to estimate the SPR property of the metal films. Also the experimental SPR angular and spectral curves are compared with theoretical simulation results. We finally conclude with the optimal metal film type and thickness and the corresponding optimal parameters for magnetron sputtering to produce the film. These results are valuable for SPR studies.