Atom beam sputtering setup for growth of metal particles in silica

A fast atom source has been installed for the synthesis of metal particles in insulating matrix. The source delivers current density of 30 μA/cm2 on the target placed at a distance of 10 cm and with variable energy ranging from 0.8 to 2.0 keV. The area of the beam is approximately 50 mm diameter. Using the setup, particles of Ag and Cu have been grown in silica matrix. The sputtered species were deposited on quartz and silicon substrate. These composite films were also prepared by co-evaporation of SiO2 and metal. The samples were annealed at different temperatures and growth of metal particles in silica matrix was investigated by the optical absorption spectrometry. Distinct surface plasma resonance peaks have been observed both from Ag and Cu particles. Mie’s theory is used to estimate the particle size. Rutherford backscattering spectrometry was used to quantify the concentration of metal fraction in the silica matrix of the composite thin films.