Investigation of Titanium Silicon and Germanium Reaction

ABSTRACTIt has been shown that, across the full range of Si-Ge alloy compositions, C54 Ti(Siy Ge1-y)2 will form from the reaction of Ti with Six Gei1-x (0 ≥ x ≥ 1.00). X-ray Absorption Fine Structure (XAFS) and X-Ray Diffraction (XRD) have been used to define consistent labeling of the C54 lattice parameters. In C54 Ti(Siy Ge1-y )2 the Si and Ge atoms occupy sites equivalent to the Si sites in C54 TiSi2. The Si and Ge atoms form shells about the Ti atoms that, within error, have Si and Ge occupancies consistent with the net Si and Ge atomic percents as determine by Auger microprobe depth profiled compositional analysis. There is an increase in the Si/Ge ratio (i.e., y>x) in the Titanium Germanosilicide. This increase may be due, in part, to the relative diffusion rates of Si, Ge, and Ti. The morphologies of the reacted films can be divided into three groups based on their similarity to the morphologies of C54 TiSi2 and C54 TiGe2 formed from similar solid phase reactions. The morphological groupings indicate that the morphology of the final C54 phase (and probably the reaction path) is strongly related to the Si/Ge content of the film.