EFFECTS OF TELLURIUM PRECIPITATES ON CHARGE COLLECTION IN CZT NUCLEAR RADIATION DETECTORS

摘要

It has been recently demonstrated that individual Tellurium (Te) precipitates identified with infrared (IR) transmission microscopes in radiation detector-grade CdZnTe (CZT) crystals correlate precisely with poor charge collection. This indicates that Te precipitates adversely affect the electron charge collection efficiency and thus the performance of nuclear radiation detectors produced from the crystals. By employing different techniques we investigated how Te precipitates affect different CZT devices. Our measurements indicate that Te precipitates put limits on the sizes, electrode configurations and spectral performance of CZT detectors. These limits can be relaxed by lowering the size and density of Te precipitates in the detectors.