Preparation of Au/SiO2 nano-composite multilayers by helicon plasma sputtering and their optical properties

Au/SiO2 nano-composite multilayers were prepared by helicon plasma sputtering. The An particles dispersed in the SiO2 matrix grew with increasing deposition time in the initial time less than 10s, then changed from network-like to film-like microstructure with increasing deposition time. The optimum deposition time for preparing the An particles was 8s, and the size of An particles was about 6 to 8 nm. The absorption peak due to the surface plasmon resonance of An particles was observed at the wavelength of 560nm in the optical absorption spectra for the as-deposited Au/SiO2 thin films containing 3.3 to 10.3 vol%Au. The intensity of the absorption peak increased with increasing An content, and the optimum An content was about 10.3 vol%.