The diffusivity of O in Czochralski-type crystals at 400 to 750C (table 11) was deduced from the macroscopic O precipitation behavior during heat treatment (800C, 4h or 1000C, 16h) by using nucleation theory. The measured O diffusivities at 450 to 650C ranged from 2 x 10-14 to 4 x 10-14cm2/s. These values were considerably higher than the generally accepted normal diffusivities, which were described by:

D (cm2/s) = 0.13 exp[-2.53(eV)/kT]

The diffusivity at 450C was found to be roughly proportional to the interstitial O concentration. It was suggested that this dependence of O diffusivity upon interstitial O concentration could be explained in terms of fast-diffusing O molecules.

Diffusivity of Oxygen in Czochralski Silicon at 400-750C H.Takeno, Y.Hayamizu, K.Miki: Journal of Applied Physics, 1998, 84[6], 3113-7

Table 11

Diffusivity of O in Si