Behavior of CdTe and CdZnTe detectors following electron irradiation

When exposed to an intense radiation field, the spectroscopic capabilities of room temperature CdTe and CdZnTe detectors can be strongly altered by the remarkable injection of energy in the material structure due to the absorption of ionizing, particles. Up to date few experimental data are available about the behavior of II-VI compound detectors to various types of radiation. For this reason we are carrying out an extended study using a large variety of particles for irradiation. In this work we report on the effects of electron irradiation both on CdTe and CdZnTe detectors. We have studied the detector response to electron irradiation through dark current measurements and by spectroscopic analyses at low and medium energies. The deep traps present in the material have been characterized by means of PICTS (photo-induced current transient spectroscopy) analyses, which allow for the determination of the trap apparent activation energy and capture cross section. The evolution of the trap parameters with increasing irradiation doses has been monitored and compared with the results already obtained by using other radiation sources