Effect of rare-earth elements on luminescence properties of ZnSe-based Chalcogenide scintillators

Afterglow in two types of semiconductor scintillators, ZnSe(Te) and ZnSe(O,Al), after pulsed X-ray excitation is studied. It is demonstrated that the afterglow can be significantly reduced by annealing in a zinc-rich atmosphere and co-doping by rare-earth elements. The co-doping also decreases the light yield of the ZnSe(Te) crystal, but has a minor influence on the light yield of annealed ZnSe(O,Al). The influence of the co-doping on carrier trapping is discussed.