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The availability of large, single crystals of cadmium zinc telluride (CZT) with uniform properties is key to
improving the performance of gamma radiation detectors fabricated from them. Towards this goal, we discuss
results obtained by computational models that provide a deeper understanding of crystal growth processes and
how the growth of CZT can be improved. In particular, we discuss methods that may be implemented to lessen the
deleterious interactions between the ampoule wall and the growing crystal via engineering a convex solidification
interface. For vertical Bridgman growth, a novel, bell-curve furnace temperature profile is predicted to achieve
macroscopically convex solid-liquid interface shapes during melt growth of CZT in a multiple-zone furnace. This
approach represents a significant advance over traditional gradient-freeze profiles, which always yield concave
interface shapes, and static heat transfer designs, such as pedestal design, that achieve convex interfaces over only
a small portion of the growth run. Importantly, this strategy may be applied to any Bridgman configuration
that utilizes multiple, controllable heating zones. Realizing a convex solidification interface via this adaptive
bell-curve furnace profile is postulated to result in better crystallinity and higher yields than conventional CZT
growth techniques.
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