X-ray photoemission spectroscopy study of silicidation of Ti on BF2 +-implanted polysilicon

Abstract

Fluorine reactions between Ti and Si at the interface during Ti silicidation at temperatures ranging from 500 to 700 °C were studied. The types of fluorosilyl moieties formed during this interaction were identified. The binding energy shifts observed in the F 1s XPS spectra during silicidation may result from Ti-F, Si-F, and Si-F-O bond formation. A further increase in the annealing temperature beyond 550°C led to significant out-diffusion of fluorine containing species from the reaction layer.