In this work, the influence of palladium addition on phase transition, surface morphology, structural, vibrational, and
electrical properties of nickel silicide is investigated at various temperatures. For Ni(Pd)Si films micro-Raman
measurements have yielded Raman phonon peaks belonging to NiSi phase, although redshifted, on par with new peaks at
322 and 434 cm-1, not determined before, which we assign to the compositional disorder, introduced by Pd. The results
have shown that Ni(Pd)Si films are thermally stable up to 900 °C, which is 100-150 °C more than that for pure NiSi
films. Applying Miedema's model we have calculated the heat of formation for Ni(Pd)Si and found it to be more
negative than that for pure NiSi, revealing a key role of Pd in the retardation of NiSi2 phase formation. AFM results have
shown that the presence of Pd favorably influences the surface morphology of NiSi, resulting in a smoother surface.
Furthermore, we have discussed the impact of annealing conditions on peculiarities of Pd diffusion, element distribution
and electrical properties of Ni(Pd)Si and NiSi films.
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