High temperature N annealing induced interstitial oxygen (Oi) precipitation was investigated in Si epitaxial layers (epilayers) grown on heavily arsenic-doped Czochralski Si wafers. Both transmission electron microscopy and secondary ion mass spectrometry data indicated a strong Oi precipitation and/or segregation in the subsurface of epilayers annealed in N2 at 1200C. The Oi precipitates had needle-like morphology with {111} habit planes along <110> directions. This precipitation was facilitated by thermal nitridation-produced vacancies or nitrogen-vacancy complexes and was sensitive to annealing conditions. Annealing in Ar or in N2 at temperature <1125C results in no epilayer subsurface Oi precipitation.

High-Temperature Nitrogen Annealing Induced Interstitial Oxygen Precipitation in Silicon Epitaxial Layer on Heavily Arsenic-Doped Silicon Wafer. Q.Wang, M.Daggubati, R.Yu, X.F.Zhang: Applied Physics Letters, 2006, 88[24], 242112 (3pp)