Kinetic analysis of C49-TiSi2 and C54-TiSi2 formation at rapid thermal annealing rates

Abstract
We have used in situ resistance versus temperature measurements to demonstrate that a 60 nm titanium thin film on polycrystalline silicon heated at rates up to 3000 °C/min always forms high‐resistivity base‐centered orthorhombic C49‐TiSi2 before the low‐resistivity face‐centered orthorhombic C54‐TiSi2 phase. Kinetic analysis of the shift in transformation temperatures with heating rate indicates that the activation energies for the formation of C49‐TiSi2 and C54‐TiSi2 are 2.1±0.2 and 3.8±0.5 eV, respectively, when formed during the same annealing cycle. The higher activation energy of formation of C54‐TiSi2 as compared to C49‐TiSi2 suggests that under very high heating rates and annealing temperatures, the formation of C49‐TiSi2 before C54‐TiSi2 might be completely or partially bypassed.