The applicability of  in situ  X-ray diffraction to the study of reactions which typify silicide thin film formation was considered. It was shown that the technique was useful for the purpose of studying kinetics and phase relationships. The only phase which was detected by  in situ  X-ray diffraction studies of Co-Si specimens which had been annealed at 400 to 450C was CoSi. The coexistence of CoSi and CoSi2 was clearly seen in samples which were annealed at 500 to 550C. At temperatures above 600C,  in situ  X-ray diffraction revealed only CoSi2. From the diffraction data, an activation energy of 1.2eV was deduced for the diffusion-controlled growth of CoSi2. It was assumed that this value was associated with grain boundary diffusion.

S.Zalkind, J.Pellag, L.Zevin, B.M.Ditchek: Thin Solid Films, 1994, 249[2], 187-94

Figure 11

Diffusivity of Co and Nb in Co2Nb

(a: 57Co in Co71Nb29, b: 57Co in Co69Nb31 c: 95Nb in Co69Nb31)