CdZnTe room temperature gamma-ray detectors

Paul Luke
Lawrence Berkeley National Laboratory


Ge detectors provide excellent energy resolution and are routinely used in many gamma-ray spectroscopy applications. However, they require cryogenic (LN) cooling due to the small band-gap of Ge. Because of that, substantial effort has been expended in the past several decades on the search and development of wide-band-gap high-Z semiconductors as room-temperature replacement of Ge detectors. CdZnTe emerged as the most promising material to date. A fortuitous combination of the charge transport properties of this material and the coplanar-grid charge sensing technique permits the production of reasonably large detectors with good energy resolution, and the possibility of achieving performance rivaling that of Ge detectors has been demonstrated. The physics behind the CdZnTe coplanar-grid detectors and some applications will be discussed.