Properties of semiconductor scintillator ZnSe : O

Abstract

Zinc selenide (ZnSe:O) single crystals doped with 2wt% of oxygen were grown by Bridgman-Stockbarger technique and annealed under excess Zn conditions. The lattice constants of the ZnSe single crystals were obtained from X-ray diffractometer (XRD) data. It is found that. after annealing at 1290 K under excess Zn conditions, the lattice constant decreases but it increases with oxygen impurity. From the absorption spectra, the band gap energies of the ZnSe single crystals were calculated by a linear fitting process. Under excess Zn conditions, the band gap energy of the ZnSe:O single crystals decreases from 2.60 to 2.58 eV with annealing but that of ZnSe single crvstals does not chanee. The maximum emission wavelength of the radio luminescence of the annealed ZnSe:O scintillator excited by X-rays was 595nm. The afterglow level of the annealed ZnSe:O scintillator after 5ms was 0.012%. The relative light output of the annealed ZnSe:O was 1.277 times higher than for CsI:Tl. The energy resolution of the annealed ZnSe:O scintillator in a size of 10x 10x 1 mm(3) was 7.4%, when it was exposed to (CS)-C-137 gamma-ray. The annealed ZnSe:O scintillator can detect charged particles and lowenergy -gamma rays.