Investigation of the defect structures in CZ silicon crystals annealed in either oxygen or nitrogen atmosphere

The defect features in the OSF-ring of CZ Si annealed in either an O2 or N2 atmosphere were investigated by MC-IR-LST, TEM and EBIC. Though oxygen precipitation still occurs, annealing in N2 results in the elimination of the stacking faults very likely due to the introduction of vacancies from the N2 atmosphere. Tiny loop-like microdefects are however observed. The EBIC contrast at the oxygen precipitates is detectable at all temperatures in the O2 annealed sample but only at low temperatures in the N2 annealed one. This suggests a smaller contamination with deep traps in the N2 annealed sample.