Abstract
The (100) and (001) thin films of β-Sn (99.999% purity) were partially melted and regrown in a transmission electron microscope at an average cooling rate of 8.3×10^<-3> to 2.7×10^<-1>K/s in order to observe the melt growth process in-situ. The growing interface was somewhat concave toward the melt and it showed the similar curvature irrespective of the film orientation and cooling rate. The average velocity of the interface first increased rapidly and then slowly as the cooling rate was raised. During the melt growth, only lineage defects, which might be composed of a dislocation array, were introduced in the grown (100) films. Most of them were formed in the solid part near the depression of solid-liquid interface and they were propagated into the newly grown crystals, while a few of them were generated in the last solidified part of a liquid pool which was left behind solid crystal. The average length of the lineage defects formed amounted to the order of 10^5 m/m^2 at any cooling rates. On the other hand, none of defects was observed in the (001) films.
