Abstract
The C49-to-C54 phase transformation of TiSi2 has been studied by in situ observation using a transmission electron microscope (TEM) and by thermal desorption spectroscopy (TDS). In situ TEM observation reveals that the interface of the transformation moves parallel to the Si substrate. The results indicate that the transition is a diffusional transformation that occurs via the short-distance diffusion of atoms, and is not a diffusionless shear transformation. Through TDS study, H2 is found to be desorbed during the transformation. The activation energy for the transformation is calculated to be 4.1 eV from the relationship between the desorption temperature and the heating rate of TDS. The phase transformation is thought to occur via lateral and massive growth, and is not simply limited by the growth rate.