Oxygen-doped ZnTe phosphors for synchrotron X-ray imaging detectors

Autor: Zhitao Kang, Y. Diawara, Brent K. Wagner, G. Mednikova, T. Thorson, Christopher J. Summers, Roger D. Durst, Hisham Menkara
Rok vydání: 2006
Předmět:
Zdroj: Journal of Electronic Materials. 35:1262-1266
ISSN: 1543-186X
0361-5235
DOI: 10.1007/s11664-006-0252-4
Popis: ZnTe:O powder phosphors were successfully prepared by a dry synthesis process using gaseous doping and etching media. It was found that dry doping by O2 through ball-milling was an effective way to synthesize ZnTe:O powder phosphors and produced a red emission centered at 680 nm with a decay time of 1.1 µs. The emission intensity of dry O2-doped samples was three times more intense than from ZnO-doped samples, possibly due to a more uniform distribution of oxygen substitution on tellurium sites. The samples annealed in a 95% N2/5% H2 forming gas atmosphere exhibited a x-ray luminescent efficiency five times higher than did powders annealed in vacuum or N2 atmosphere. This enhancement was attributed to the removal of surface tellurium oxides. ZnTe:O phosphor screens were prepared with x-ray luminescence efficiencies equivalent to 56% of ZnSe:Cu,Ce,Cl and 76% of Gd2O2S:Tb screens under 17-keV radiation. An x-ray imaging resolution of 2.5 lines/mm was resolved, the same as that measured for commercial ZnSe:Cu,Ce,Cl and Gd2O2S:Tb screens. These results indicate that ZnTe:O is a promising phosphor candidate for synchrotron x-ray imaging applications.
Databáze: OpenAIRE
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