Characterization of indirect X-ray imaging detector based on nanocrystalline gadolinium oxide scintillators for high-resolution imaging application

摘要

Nanocrystalline Gd_2O_3:Eu scintillating powders were successfully synthesized through a co-precipitation process for X-ray imaging detector applications. In this work, as-synthesized sample was further calcinated at different temperature, time with 1-10 h and doped-Eu~(3+) concentration with 1-10 mol% in the electrical furnace. The characterization such as the crystal structures and microstructure of Gd_2O_3:Eu scintillator were measured by XRD and SEM experiment. The phase transition from cubic to monoclinic structure was observed at 1300℃ calcination temperature. Dominant emission peak of sample with cubic structure was appeared at 611 nm under 266 nm UV light excitation. After scintillation properties of synthesized Gd_2O_3:Eu scintillator were investigated, Gd_2O_3:Eu scintillating films with different thickness was fabricated onto glass substrate by a screen printing method. And then X-ray imaging performance in terms of the light response to X-ray exposure dose, signal-to-noise ratio (SNR) and spatial resolution were measured by combining the fabricated Gd_2O_3:Eu screen films with a lens-coupled CCD imaging detector under radiographic system conditions.