C49–C54 phase transition in nanometric titanium disilicide nanograins

The first order C49–C54 phase transition was studied in single TiSi 2 grains embedded in a Si matrix by transmission electron microscopy and X-ray diffraction. The fraction of material transformed into C54 was determined at different times during the annealing in the 700–1100 °C temperature range. The fraction of C54 increases with temperature and the steady state value is reached in times of ∼60 s. The data are interpreted in terms of heterogeneous nucleation at the silicide–silicon interface.