Enhanced Diffusion of Dopants in Vacancy Supersaturation Produced by MeV Implantation

Abstract

ABSTRACTThe diffusion of Sb and B markers has been studied in vacancy supersaturations produced by MeV Si implantation in float zone (FZ) silicon and bonded etch-back silicon-on-insulator (BESOI) substrates. MeV Si implantation produces a vacancy supersaturated near-surface region and an interstitial-rich region at the projected ion range. Transient enhanced diffusion (TED) of Sb in the near surface layer was observed as a result of a 2 MeV Si+, 1×1016/cm2, implant. A 4× larger TED of Sb was observed in BESOI than in FZ silicon, demonstrating that the vacancy supersaturation persists longer in BESOI than in FZ. B markers in samples with MeV Si implant showed a factor of 10× smaller diffusion relative to markers without the MeV Si+ implant. This data demonstrates that a 2 MeV Si+ implant injects vacancies into the near surface region.