Compositional analysis of atom beam co-sputtered metal-silica nanocomposites by Rutherford backscattering spectrometry

Metal:SiO2 (metal: Ni, Ag, Au) nanocomposite films of different compositions have been prepared by atom beam co-sputtering. The estimation of composition of films is done theoretically using sputtering yield and relative area of metal and SiO2. The sputtering yields used for estimation of composition are calculated by three theoretical methods: Monte Carlo simulations (SRIM code), Sigmund's theory and Sigmund's theory modified by Anderson and Bay. Rutherford backscattering spectrometry (RBS) is also used to analyze the composition of the nanocomposite films. RUMP simulations of RBS data are performed. The errors in theoretical calculations and RBS results are estimated. It is found that SRIM is more appropriate for Ni:SiO2, nanocomposite films, while modified Sigmund's theory based method is better for Ag:SiO2 and Au:SiO2 nanocomposite films. The possible sources of errors in theoretical methods with respect to experimental (RBS) results are also discussed. (C) 2008 Elsevier B.V. All rights reserved.