Evaluation of THM-Grown CdZnTe Material for Large-Volume Gamma-Ray Detector Applications

Abstract

Over 25 1-cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> CdZnTe crystals produced using the Traveling Heater Method at Redlen Technologies have been characterized. The charge carrier mobility and lifetime, and charge carrier transport uniformity of each crystal were measured using alpha particles. Some of the crystals were made into coplanar-grid detectors and their performance characterized using 662 keV gamma rays. The average electron mobility-lifetime product for these crystals was found to be a factor of about five times greater than that measured from crystals obtained over the last decade from two other commercial crystal growers. The coplanar-grid detectors produced from the material typically achieved an energy resolution at 662 keV near 2% FWHM when operated at room temperature. This is comparable to the best coplanar-grid detectors commercially produced today.