Crystal growth at the interface between silica glass and molten silicon was
investigated to clarify the formation process of a ring structure at the s
urface of Czochralski crucibles. A cluster of faceted cristobalite at the i
nterface was found to grow laterally and then transform into a ring with di
sappearance of the faceted crystals at the, central region. The production
of the cristobalite cluster is explained by dissolution of silica glass int
o molten silicon and deposition of crystalline cristobalite at a nucleation
site. Redissolution of the crystal at the central area of the cluster resu
lted in the formation of a ring structure. It is deduced that the nucleatio
n site of cristobalite clusters is provided by the devitrification of silic
a glass. (C) 2000 The Electrochemical Society. S0013-4651(98)11-099-6. All
rights reserved.