Atomistic study of sulfur diffusion and S2 formation in silicon during low-temperature rapid thermal annealing

Theoretical analyses predict that large Schottky barrier reduction by sulfur doping at NiSi/Si junction is induced by S2 formation. The S2 formation may have occurred in silicidation process, even under low temperature rapid thermal annealing. We have demonstrated that implanted sulfur into silicon forms S2 configuration under low temperature rapid thermal annealing, based on first principles calculations and kinetic Monte Carlo (KMC) simulations.