The mobility-lifetime product of hole in CdZnTeSe depending on Se contents

The charge collection efficiency (CCE) of a radiation detector greatly depends on the ratio of the electron to hole mobility-lifetime product. In order to improve the energy resolution of the detector, it is crucial to minimize the effects of hole tailing effect and the polarization effect. A recent study has shown that the addition of Se to CdZnTe (CZT) detectors can improve the mobility-lifetime product of holes by reducing the density of Ec-1.1-eV traps (hole traps) [1]. To determine the optimal amount of Se, the mobility-lifetime product of holes in CdZnTeSe (CZTS) detectors was evaluated with Se contents ranging from 1% to 10%. The Zn content was adjusted accordingly to compensate for the decrease in bandgap at higher Se contents. The detector performance and mobility-lifetime products of holes at different Se contents will be presented.