Maintaining convex interface shapes during electrodynamic gradient freeze growth of cadmium zinc telluride using a dynamic, bell-curve furnace profile

A novel, bell-curve furnace temperature profile is presented and predicted to achieve macroscopically convex solid–liquid interface shapes during melt growth of CZT in an EDG furnace. A strategy is also presented to dynamically adapt this furnace profile so that uniform, convex interface shapes are maintained through an entire growth run. 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.

► A bell-curve furnace profile is tested in a model for EDG CZT growth.
► A macroscopically convex solid–liquid interface shape is attained via this profile.
► A dynamic profile is needed to maintain convex interface shapes during growth.