Annealing of heavily arsenic-doped silicon: Electrical deactivation and a new defect complex

Ab initio total-energy calculations indicate that the formation of a new defect complex, a vacancy surrounded by four arsenic atoms, is responsible for electrical deactivation and for structural changes seen in measurements of extended x-ray-absorption fine structure when heavily arsenic-doped silicon is annealed. The v-As4 complex is energetically favored over both substitutional, isolated As in Si and substitutional Si-As4 configurations, and it is neutral and electrically inactive. The formation of such defects may be a widespread occurrence in silicon and in other semiconductors. © 1988 The American Physical Society.