Anisotropic small-angle neutron scattering from oxide precipitates in silicon single crystals

Anisotropic small-angle neutron scattering has been observed from Czochralski-grown silicon single crystals annealed for different times at 750 degrees C. This scattering has been attributed to oxide platelet precipitates lying on the (100) planes. The precipitate size, number density and oxygen concentration in the matrix are obtained from the analysis of this scattering. The oxygen diffusion coefficient has been calculated from the increase in the size of the precipitates with anneal time and it is found to be in agreement with the value obtained from mass transport experiments. The loss of solute oxygen from the matrix follows the equation derived by Ham (1958).