Thirteen ingots of undoped InSb, Te-doped InSb and Se-doped InSb were directionally solidified in a gradient freeze furnace mounted at the end of the 18 m arm of a centrifuge in the USSR. Each ingot was subjected to a different acceleration level during growth. One Se-doped InSb ingot was solidified in a centrifuge in France with an arm length of 5.5 m. An undoped InSb ingot grown at 9 g (g = 9.81 m/s{dollar}sp2{dollar}) consisted primarily of a single grain containing a number of twins. The microstructure of the ingots depended on the acceleration and on the doping. Te-doped InSb grown at 9 g had the fewest grain and twin boundaries, while Se-doped InSb grown at 9 g had the most grain boundaries. For undoped ingots, InSb grown at 7 g had the fewest twin boundaries. Reproducibility experiments on grain and twin boundary counts showed that differences in microstructure seen in the ingots solidified in the centrifuges were statistically significant. No dopant striations were observed in any of the ingots, indicating that the freezing rate did not fluctuate. With doping, microcracks sometimes occurred, but never without doping. Centrifuge processing almost completely eliminated the bubbles normally present on the outer surface of InSb ingots. Undoped InSb ingots were either n or p-type, while Te and Se-doped ingots were n-type. The axial hole concentration in undoped InSb grown at 9 g was constant. Polycrystallinity of the InSb ingots caused a lot of scatter in resistivity and mobility data.; HIRB (High Inertia Rotating Behemoth) is a novel modification of a variable speed, 62 inch King boring mill. The arm radius for experiments is 1.524 m. The maximum rotation rate attainable is 90 rpm, which corresponds to a maximum acceleration of {dollar}approx{dollar}15 g. The centrifuge was instrumented with equipment for performing crystal growth experiments at high gravity.; Ten ingots of Te-doped InSb were directionally solidified in a gradient freeze furnace mounted at the end of the arm of HIRB at various acceleration levels. All ingots were polycrystalline. Ingots grown at 2 g had the fewest grains compared to the ingots grown at other acceleration levels. Growth of InSb at high acceleration reduced the bubbles present on the outer surface of the ingots. No distinct trend in the resistivity with acceleration was observed in either the axial or radial directions. Ten ingots of doped InSb were grown to try to produce interface demarcations by using incremental quenching, complete quenching and melt-back and regrowth techniques. No striations were obtained. Furnace power consumption decreased from 1 g to 2 g. Between 2 g and 8 g the furnace power consumption was almost constant. Acceleration and vibration analysis on HIRB revealed a 17 Hz low frequency vibration component in the direction of rotation of the centrifuge. (Abstract shortened by UMI.)
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