Influence of melt motion on the shape of molten zone in the FZ crystal growth process

K. Dadzis¹ - A. Muiżnieks¹ - A. Rudeviċs¹ - H. Riemann² - A. Lüdge²

¹ Faculty of Physics and Mathematics, University of Latvia, 8 Zellu str., LV-1002 Riga, Latvia
² Institute of Crystal Growth, Max-Born Str. 2, D-12489 Berlin, Germany

Abstract
In numerical simulations of the floating-zone crystal growth process, the shape of phase boundaries is unknown beforehand and must be obtained as a part of the solution. One of the factors, which may influence the shape of phase boundaries significantly, is convective heat transfer in the molten zone. The present paper offers an analysis based on mathematical modelling of the influence of the melt motion on the shape of phase boundaries by investigating a specific 2'' floating zone growth system and compares the modelling results with experiment. A needle-eye inductor is used in the growth system leading to curved boundaries of the molten zone and to strong high-frequency electromagnetic forces in the melt. The influence of the melt motion on the crystallization interface is also estimated analytically. Figs 12, Refs 8.