Surface Plasmon Resonance and Raman Scattering Activity of the Au/Ag_xO/Ag Multilayer Film

The nanostructured Au/Ag_xO/Ag sandwich multilayer films on quartz substrates are prepared by the magnetron sputtering method. The morphology, plasmon resonance and surface enhanced Raman scattering (SERS) activities of the multilayer films are studied. The resonant absorption wavelength of localized surface plasmon is tuned in a wide range from 618 nm to 993 nm by controlling the density of nanoparticles of Au and Ag. The SERS activity of the Au/Ag_xO/Ag multilayer films are enhanced over ～10 times compared with those of bare Ag and bare Au films. These properties may find a potential application in biosensor and bioimaging.