A new CdZnTe detector system for low-energy gamma-ray measurement

The major problems with CdTe-based radiation detectors have been excess noise and operation instabilities due to poor charge-collection efficiency. New fabrication methods have removed these problems and made CdZnTe detectors attractive in applications where compact room-temperature detectors with high stopping efficiency are required. The improvements in this detector technology are demonstrated. The noise performance of these detectors is comparable with that of silicon detectors. Gamma-ray densitometry and tomography are typical applications where fast and compact detector systems are required. A system based on a delay-line shaping amplifier circuit has been developed for this purpose, but is also applicable in other high-count-rate applications. The principle of operation and the test results of this system are presented.