Silicide formation in thin Co/poly-Si layers capped with Ti during annealing (420 to 510C) was investigated by time-resolved sheet resistance measurements. It was found that CoSi2 nucleation was a fast process while Co diffusion through CoSi2 grain boundaries was a slow process. Simulations of the resistance curves versus time showed that the pre-exponential factor for Co diffusivity was reduced by the presence of Ti contamination at the CoSi2 grain boundaries, as was shown by energy-filtered transmission electron microscopy analysis, while the activation energy did not change with respect to a reference.

Effect of a Ti Cap Layer on the Diffusion of Co Atoms during CoSi2 Reaction. A.Alberti, R.Fronterrè, F.La Via, E.Rimini: Electrochemical and Solid-State Letters, 2005, 8[2], G47-50