2014 Volume 31 Issue 3 Pages 106-
The microgravity experiment mission FACET (Investigation on Mechanism of Faceted Cellular Array Growth) was carried out under long duration microgravity on the International Space Station (ISS) in 2010. FACET aimed to clarify the mechanism of a faceted cellular array growth by precisely observing the phenomena at the solid/liquid interface. Phenyl salicylate / t- butyl alcohol alloy was used as a sample material instead of semiconductors or oxides. The crystal growth processes were visualized in situ using a microscope and an interferometer, especially focusing on changes in temperature and concentration in the sample. The temperature and concentration distributions in the melt during the growth were precisely measured with high spatial resolution. Negative temperature gradient as well as negative concentration gradient ahead of the S/L interface can be expected to be the driving forces of the morphological instability. It is evident that the conventional model based on the frozen temperature approximation is insufficient to explain the growth mechanism of the faceted cellular array
