The properties of isolated O, C, N and H were considered with respect to O precipitation above and below 500C. Thermal donors formed at the lower temperatures. In order to generate O clusters that contained up to some 10 atoms at 450C, it was necessary to take the dissociation of smaller O clusters into account and to assume the rapid diffusion of O2 dimers. It was demonstrated that as-grown Czochralski crystals could contain H which enhanced the diffusion of single O atoms. These impurities were also incorporated into certain O clusters which acted as shallow donors. It was suggested that dimer interaction with Oi atoms led to an enhancement of the O diffusivity.

R.C.Newman: Materials Science and Engineering B, 1996, 36[1-3], 1-12