中国物理B ›› 2011, Vol. 20 ›› Issue (4): 42901-042901.doi: 10.1088/1674-1056/20/4/042901
雷耀虎, 刘鑫, 郭金川, 赵志刚, 牛憨笨
Lei Yao-Hu(雷耀虎), Liu Xin(刘鑫), Guo Jin-Chuan(郭金川), Zhao Zhi-Gang(赵志刚), and Niu Han-Ben(牛憨笨)†
摘要: In order to push the grating-based phase contrast imaging system to be used in hospital and laboratories, this paper designs and develops a novel structure of x-ray scintillator functioning also as an analyser grating, which has been proposed for grating-based x-ray differential phase contrast imaging. According to this design, the scintillator should have a periodical structure in one dimension with the pitch equaling the period of self-image of the phase grating at the Talbot distance, where one half of the pitch is pixellated and is made of x-ray sensitive fluorescent material, such as CsI(Tl), and the remaining part of the pitch is made of x-ray insensitive material, such as silicon. To realize the design, a deep pore array with a high aspect ratio and specially designed grating pattern are successfully manufactured on 5 inch silicon wafer by the photo-assisted electrochemical etching method. The related other problems, such as oxidation-caused geometrical distortion, the filling of CsI(Tl) into deep pores and the removal of inside bubbles, have been overcome. Its pixel size, depth and grating pitch are 3 μm×7.5 μm, 150 μm and 3 μm, respectively. The microstructure of the scintillator has been examined microscopically and macroscopically by scanning electron microscope and x-ray resolution chart testing, respectively. The preliminary measurements have shown that the proposed scintillator, also functioning as an analyser grating, has been successfully designed and developed.
中图分类号: (Scintillation detectors)