Analytical modelling of floating zone crystal growth

An analytical model for predicting the outer shape evolution of a crystal grown by the floating zone technique is developed. The analysis is axisymmetric and linear in the departure from a cylindrical evolution, thus it only applies to crystal growth under negligible external force fields (e.g. under microgravity), when the seed and feed sizes do not differ too much, and when radial deformations are not pronounced. In spite of these limitations, the analytical model clearly shows that, depending on the slenderness of the molten bridge, the processing may give rise to steady growth (after some transients) or just to a breakage by capillary forces. (C) 2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.