The influence mechanism of melt flow instability on the temperature fluctuation on the crystal/melt interface during Czochralski silicon crystal growth

摘要

The temperature fluctuation on the crystal melt interface during Czochralski silicon crystal growth is firstly investigated with LES method based on the relationship between kinetic undercooling and growth rate. The effects of crystal and crucible rotation on the temperature fluctuation are analyzed. The results show that when crystal counter-rotates with crucible, the temperature fluctuations on the interface and that in the melt close to crystal are more intense compared with co-rotation. The characteristic frequencies of temperature fluctuations on the interface and that in the melt are identical for counter-rotation. However, this consistency of the characteristic frequencies is not obvious for co-rotation. In particular, the temperature fluctuations on the interface are about 0.4 K and 0.7 K for co-rotation and counter rotation, respectively. Importantly, the influence mechanism of melt flow instability on temperature fluctuation is clarified by the analyses of cross-correlation and local convective heat transport. (C) 2019 Elsevier Ltd. All rights reserved.