RESUMO
Microgravity crystal growth experiment for the growth of In0.11Ga0.89Sb was performed at the Chinese recoverable satellite through the space program SJ-10. This experiment is aimed to understand the melt formation and growth kinetics of In x Ga1-x Sb solid solution with higher indium composition, because their segregation coefficient was higher than the crystals with lower indium compositions. The target composition and uniformity were achieved with higher growth rate under microgravity, whereas the uniformity in composition was not achieved under normal gravity. The growth and dissolution were affected mainly by the steady state equilibrium in the melt composition because of the convection under normal gravity. The non-steady state equilibrium in the melt composition under microgravity helped to achieve a higher growth rate and compositional homogeneity at higher indium composition of In x Ga1-x Sb solid solution.
RESUMO
InGaSb ternary alloys were grown from GaSb (111)A and B faces (Ga and Sb faces) under microgravity conditions on board the International Space Station by a vertical gradient freezing method. The dissolution process of the Ga and Sb faces of GaSb and orientation-dependent growth properties of InGaSb were analysed. The dissolution of GaSb(111)B was greater than that of (111)A, which was found from the remaining undissolved seed and feed crystals. The higher dissolution of the Sb face was explained based on the number of atoms at that face, and its bonding with the next atomic layer. The growth interface shape was almost flat in both cases. The indium composition in both InGaSb samples was uniform in the radial direction and it gradually decreased along the growth direction because of segregation. The growth rate of InGaSb from GaSb (111)B was found to be higher than that of GaSb (111)A because of the higher dissolution of GaSb (111)B.