Chemical Bonding Features of Fluorine and Boron in BF2 +-Ion-Implanted Si

Abstract
The chemical bonding configurations of fluorine and boron atoms in a BF2 +-ion-implanted Si network have been studied by using X-ray photoelectron spectroscopy, infrared absorption and Raman scattering measurements. It is concluded that fluorine atoms in as-implanted Si are mainly incorporated as BF bonds. By annealing at 900°C, the BF bonds are thermally decomposed to form four fold-coordinated acceptors as well as thermodynamically stable SiF x bonds (x=2, 3) in the matrix.