CdTe and CdZnTe materials have been studied for more than forty and twenty years, respectively, for producing room-temperature gamma ray detectors for Nuclear Physics research. Despite measurable success in the application of the detectors, detector production yield has been low and detector performance has been below the theoretical prediction. The major handicap in advancing CdZnTe technology is a lack in understanding the material properties. In recent research, a comprehensive theoretical model was developed to interpret defect dynamics in CdZnTe, leading to an innovative technique for reducing Cd vacancies, one of the major defects that degrade the detector properties. In this project, this defect reduction technique will be fully developed to drastically reduce the density of all CdZnTe defects. In Phase I, the Cd vacancy reduction technique will be advanced. In addition, CdZnTe growth parameters will be significantly modified to reduce Te antisites, the other major defect in CdZnTe. Detectors will be fabricated with the advanced materials and tested.
Commercial Applications and Other Benefits as described by the awardee: Improved CdZnTe detectors and imaging systems should have application to crystallography, astronomy, security inspection, industrial process control, and medical imaging. The annual market for x-ray and gamma ray equipment is in the billions of dollars
