SILICIDE FORMATION

The physical mechanisms responsible for silicide formation are reviewed. The analysis includes phase formation, impurity effects, alloy crystallization, oxidation, impurity distribution and electrical properties. The data are presented referring, when possible, to the Ti-Si system. TiSi2 has two different crystalline structures: one orthorhombic base-centred C49 structure, which forms at low temperatures (around 400°C), and another, orthorhombic face-centred C54 structure, which forms around 700°C. Once the face-centred phase is formed it is stable irrespective of the annealing processes subsequently performed.