Ion beam photography in sol-gel NiO-SiO2 films

Composite oxide films (NiO-SiO2) were deposited on silicon wafers using the sol-gel dip coating technique. The average stoichiometry [NiO]/[SiO2], adjusted from the molar ratio of the two starting precursors, was typically 10%. Single and multilayer coatings were used to obtain film thicknesses from 70 to 400 nm. The samples were then irradiated at room temperature with MeV ions in the 10(12)-10(14) cm(-2) fluence range and further annealed at low temperature in argon atmosphere. Our first cross-sectional transmission electron microscopy studies show that such a treatment induces the nucleation and growth of pure Ni clusters. Some information is obtained on the specific features due to the sol-gel fabrication process. (C) 2002 Elsevier B.V. All rights reserved.