Structural characterization and oxygen concentration profiling of a Co/Si multilayer structure

We report an accurate characterization (by RBS and XRD) of the stoichiometry and the phase formed in a multilayer sample (20 layers), constituted by the repetition of the stack 1.5 nm Co/27 nm Si. The samples were prepared by physical vapor deposition at a pressure of similar to10(-8) Torr. The multilayer structure is amorphous and a limited amount of mixing at the Si/Co interface occurs during deposition. Annealing at 600 degreesC resulted in the formation of a multilayer constituted by CoSi2/Si layers. Resonant backscattering spectrometry using a 3.036 MeV He+ has been used to quantify the oxygen contamination occurring during the deposition process.