Rummukainen M, Makkonen I, Ranki V, Puska M J, Saarinen K, Gossmann H-J L
Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT, Finland.
Phys Rev Lett. 2005 Apr 29;94(16):165501. doi: 10.1103/PhysRevLett.94.165501. Epub 2005 Apr 25.
Positron annihilation measurements, supported by first-principles electron-structure calculations, identify vacancies and vacancy clusters decorated by 1-2 dopant impurities in highly Sb-doped Si. The concentration of vacancy defects increases with Sb doping and contributes significantly to the electrical compensation. Annealings at low temperatures of 400-500 K convert the defects to larger complexes where the open volume is neighbored by 2-3 Sb atoms. This behavior is attributed to the migration of vacancy-Sb pairs and demonstrates at atomic level the metastability of the material grown by epitaxy at low temperature.
