The C49ÞC54 TiSi polymorphic transformation has been investigated trying to elucidate the relative role played by 2 nucleation and growth in silicide formation. Samples having an amorphous layer and C54 seeds have been made by heat treatment of a Ti / Si bi-layer structure and subsequent suitable Ar ion implantation. In situ resistance measurements performed during heat treatments in controlled and purified atmosphere at constant heating rates and ex situ X-ray diffraction, MeV 4He+ backscattering spectrometry and cross-section transmission electron microscopy have been used to characterize the samples. The results show that in a sample with C49 the C54 nucleation occurs at 800°C; when C54 seeds are present the growth is appreciable already at temperatures as low as 400–500°C. It has also been shown that nucleation and growth of the C49 phase is a process competitive to the growth of the C54 phase.
Investigation of C49-C54 TiSi2 Transformation kinetics
Giubertoni, Damiano;
2000-01-01
Abstract
The C49ÞC54 TiSi polymorphic transformation has been investigated trying to elucidate the relative role played by 2 nucleation and growth in silicide formation. Samples having an amorphous layer and C54 seeds have been made by heat treatment of a Ti / Si bi-layer structure and subsequent suitable Ar ion implantation. In situ resistance measurements performed during heat treatments in controlled and purified atmosphere at constant heating rates and ex situ X-ray diffraction, MeV 4He+ backscattering spectrometry and cross-section transmission electron microscopy have been used to characterize the samples. The results show that in a sample with C49 the C54 nucleation occurs at 800°C; when C54 seeds are present the growth is appreciable already at temperatures as low as 400–500°C. It has also been shown that nucleation and growth of the C49 phase is a process competitive to the growth of the C54 phase.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
