From out-diffusion profiles of oxygen in Czochralski silicon at 500C, measured using secondary ion mass spectrometry, oxygen diffusivities of 2.5 x 10−14 to 4.0 x 10−14cm2/s were deduced. These were enhanced by nearly four orders of magnitude, relative to the normal diffusivity. The diffusion of implanted 18O in float‐zone silicon at 400 to 525C yielded profiles which consisted of an exponential decay of the oxygen concentration. Exponential profiles of 18O above the background (1014/cm3), as deep as 4 to 16μm, also revealed direct evidence of enhanced long‐range oxygen diffusion. The results of enhanced oxygen diffusion could be explained in terms of a fast‐diffusing species which was in dynamic equilibrium with interstitial oxygen.

Enhanced Oxygen Diffusion in Silicon at Thermal Donor Formation Temperature. S.T.Lee, P.Fellinger: Applied Physics Letters, 1986, 49, 1793