中国物理B ›› 2011, Vol. 20 ›› Issue (4): 42901-042901.doi: 10.1088/1674-1056/20/4/042901

• NUCLEAR PHYSICS • 上一篇    下一篇

Development of x-ray scintillator functioning also as an analyser grating used in grating-based x-ray differential phase contrast imaging

雷耀虎, 刘鑫, 郭金川, 赵志刚, 牛憨笨   

  1. Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education, Institute of Optoelectronics, Shenzhen University, Shenzhen 518060, China
  • 收稿日期:2010-08-11 修回日期:2010-10-09 出版日期:2011-04-15 发布日期:2011-04-15
  • 基金资助:
    Project supported by the Major Program of the National Natural Science Foundation of China (Grant No. 60532090).

Development of x-ray scintillator functioning also as an analyser grating used in grating-based x-ray differential phase contrast imaging

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)   

  1. Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education, Institute of Optoelectronics, Shenzhen University, Shenzhen 518060, China
  • Received:2010-08-11 Revised:2010-10-09 Online:2011-04-15 Published:2011-04-15
  • Supported by:
    Project supported by the Major Program of the National Natural Science Foundation of China (Grant No. 60532090).

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.

Abstract: 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.

Key words: scintillator screen, pore arrays, oxidation, CsI(Tl), analyser grating

中图分类号:  (Scintillation detectors)

  • 29.40.Mc
07.85.Fv (X- and γ-ray sources, mirrors, gratings, and detectors) 87.57.cf (Spatial resolution)