The interaction of intrinsic oxygen in Czhochralski silicon with implantation damage induced by 2.0 MeV Si+ions has been investigated as a function of annealing temperature and time. Four distinct regions of oxygen localization are revealed by secondary ion mass spectrometry following sample annealing. The different regions are correlated with either a near surface vacancy‐rich region or the buried layer of extended defects near the projected range. The relative concentration of oxygen in each region depends on the competition between oxygen gettering in each region and out‐diffusion to the surface. It has been established, using quasikinematical and dynamical contrast transmission electron microscopy imaging techniques, that the oxygen in regions containing extended dislocations is in the form of fine precipitates. The precipitates decorate both the dislocations and, for faulted loops, the stacking fault planes. ©1996 American Institute of Physics.