Oxidation induced precipitation in Al implanted epitaxial silicon

The behavior of Al implanted in silicon has been investigated during therma l oxidation. It has been found that precipitation of Al into Al-O-defect co mplexes depends on the implant energy, i.e., on the distance of the dopant from the surface. It occurs at 650 keV, but it does not at 2.0 MeV or highe r energies. This phenomenon has been explained taking into account the diff usivity of self-interstitials introduced during oxidation, the oxygen prese nt in the Si, the Al concentration, and the annealing out of defects. (C) 2 000 American Institute of Physics. [S0021-8979(00)06120-X].