Vacancy-based micro-defects in Czochralski-type material, such as voids and oxide particles, were nucleated simultaneously during cooling. The nucleation rate attained a sharp peak at some nucleation temperature, because vacancy loss to the growing micro-defects suppressed further nucleation.. The species which was mainly responsible for the loss was normally voids. A quantitative model of void formation was considered which predicted the nucleation temperature, density and size of voids as a function of the initial vacancy concentration and cooling rate. A decrease in the initial vacancy concentration resulted in a change of the dominant species from voids to particles. It was recalled that Si crystals often consisted of 2 two neighboring zones (vacancy and interstitial), and the vacancy zone could be further sub-divided into an inner void region and a marginal particle band. Vacancy properties, such as the diffusivity and equilibrium concentration, could be deduced from data on grown-in voids.

Vacancy-type microdefect formation in Czochralski silicon V.V.Voronkov, R.Falster: Journal of Crystal Growth, 1998, 194[1], 76-88