Thermal and ion-induced dissociation of NiSi and NiSi2 in contact with nickel

The interaction of nickel with NiSi and NiSi₂ was investigated using backscattering spectrometry and glancing angle X-ray diffraction. With nickel films deposited onto NiSi or NiSi₂, Ni₂Si was formed at the original compound-nickel interface by the dissociation of the compounds on annealing at temperatures of about 300 °C. The dissociation of NiSi and NiSi₂ into Ni₂Si has also been observed when the samples were irradiated with argon ions. We attribute similarities in the two processes to the presence of thermodynamic forces in ion-induced reactions and the dependence of the radiation-enhanced migration on the intrinsic diffusion properties in the system.