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Large Volume Detectors from New CdZnTe Growth Process--Radiation Monitoring Devices, Inc., 44 Hunt Street, Watertown, MA 02172-4624; 617-926-1167
Dr. Michael R. Squillante, Principal Investigator
Dr. Gerald Entine, Business Official
DOE Grant No. DE-FG02-99ER82865
Amount: $100,000
During the past decade, revolutionary new x- and g -ray detector designs have been proposed based upon the semiconductor cadmium zine talluride (CdZnTe). While their demonstrated promise has been very good, their real future requires a consistent and cost effective supply of high quality, large volume substrates needed for detector fabrication. Current CdZnTe fabrication suffers from significant material defects, electrical nonuniformities, and prices exceeding $1000/cm3. Detector grade CdZnTe has previously been grown by largely one method. This project will develop an alternative crystal growth technique that has been used with great success in the fabrication of IR detector substrates. While known to yield exceptional physical properties, this technique must be extended to achieve the stringent electrical properties needed for g -ray detection. In Phase I, the crystal growth will be tested under varying inert and Cd vapor pressures, and with addition of an additive dopant. Several electrical criteria will be evaluated to determine whether the growth technique can achieve the necessary detector properties.
Commercial Applications and Other Benefits as described by the awardee: More available, lower cost CdZnTe substrates should allow new detector designs to become feasible. In nuclear physics, high densities of less cumbersome detectors would lead to faster and more complete data. Other applications include nuclear medicine imaging, nonproliferation monitoring capabilities, and industrial non-destructive evaluation.