High-Performance, Large-Volume THM CdZnTe Detectors for Medical Imaging and Homeland Security Applications

High-quality large single crystals of Cd0.9Zn0.1Te (> 7 inch3) have been consistently produced by the THM (solution growth) method. Various large-volume X-ray and gamma-ray detector configurations fabricated from this THM CZT material have produced detectors with excellent performance. A room-temperature mean energy resolution of 4.3% for a Co-57 source (122 keV) and uniform pixel-to-pixel response have been demonstrated on monolithic 20times20times5 mm3 pixellated detectors useful for imaging applications. In addition, energy resolution of <1% FWHM @ Cs-137 (662 keV) has been measured on virtual Frisch-Grid 4times4times11 mm3 devices useful for homeland security applications. Additional characterization techniques such as mu-tau measurements, infrared microscopy, X-ray topography and ODLTS have demonstrated the superior quality of this THM CZT. The results of material characterization measurements and detector tests will be presented.

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