It was recalled that Si(100) and (111) oriented Si wafers were used as substrates for metallic bilayer deposition of Cu and Au. Cu/Au/Si structures were obtained by thermal evaporation and then heated below 400C in vacuum. These solid-state reactions occurred in the samples were studied using X-ray diffraction, Rutherford back-scattering spectroscopy, scanning electronic microscopy and X-ray dispersive energy analyzer. The study showed that heat treatment at 200C of the multi-layered Cu/Au/Si structure leads to the formation and the co-existence of both Cu3Si and Cu4Si Cu rich-silicides with the expansion of their respective cells, independently of the orientation of the substrate. Increasing the annealing temperature to 400C led to the growth of well-oriented crystallites corresponding to Cu3Si and Cu4Si silicides on Si(111) but only Cu4Si crystallites with square and rectangular shapes on Si(100). The thermal stability of formed Cu silicides after heat treatment (400C, 0.5h) for both Cu/Au/Si(100) and Cu/Au/Si(111) systems was analyzed.

Atomic Diffusion at the Cu–Au–Si Multilayers Interface. S.Iaiche, N.Benouattas, A.Bouabellou, L.Osmani, L.Salik: Microelectronic Engineering, 2005, 81[2-4], 349-52