Wj. Yuan et al., THE EFFECT OF VERTICAL VIBRATION OF THE AMPOULE ON THE DIRECTIONAL SOLIDIFICATION OF INSB-GASB ALLOY, Journal of crystal growth, 151(3-4), 1995, pp. 235-242
The effects of vertical vibration of the ampoule on the directional so
lidification of InSb-GaSb alloy in the vertical Bridgman-Stockbarger c
onfiguration were investigated. The microstructure and compositional p
rofile of In0.2Ga0.8Sb grown with and without vibration were studied.
The axial composition profile with and without vibration corresponded
to complete mixing of the melt. No significant radial composition vari
ations were observed. Though twins were slightly increased by the appl
ication of vibration, the number of grain boundaries in the ingots gro
wn with vibration was less than in ingots grown without vibration, esp
ecially in the first-to-freeze parts. With the application of vertical
vibration with 20 Hz frequency/0.5 mm amplitude to the growth ampoule
, the ingots had the fewest grain boundaries. Vibration did not change
the interface shape significantly during the first part of the ingots
. However, the interface became more concave during the last part of t
he solidification when vibration was applied. Twinning mostly initiate
d from the edge of the ingot where they contacted with the ampoule wal
l.