Investigation on C54 nucleation and growth by micro-Raman imaging

The processes of nucleation and growth of the C54 TiSi2 phase into the C49 phase in thin films have been studied by electrical measurements and micro-Raman spectroscopy. The Raman spectra have been acquired scanning large silicide areas (100x50 um2) in step of 0.5 um. Images showing the evolution of the C54 grains during the transition have been obtained for temperatures between 680 and 720 °C and the transformed fraction, the density and the size distribution of the C54 grains have been measured as a function of the temperature and the annealing time. The activation energies for the nucleation rate and the growth velocity have been determined obtaining values of 4.9± 0.7 eV and 4.5± 0.9 eV, respectively.