φ100 mm级Ca∶Ce∶LYSO闪烁晶体生长及闪烁性能研究

人工晶体学报 ›› 2021, Vol. 50 ›› Issue (10): 1946-1950.

φ100 mm级Ca∶Ce∶LYSO闪烁晶体生长及闪烁性能研究

王佳, 岑伟, 丁雨憧, 王强, 张泽涛

中国电子科技集团公司第二十六研究所,重庆 400060

收稿日期:2021-08-30 出版日期:2021-10-15 发布日期:2021-11-24
作者简介:王佳(1981—),女,黑龙江省人,高级工程师。E-mail:jiawang1224@163.com。王佳(1981—),女,硕士,中国电子科技集团公司第二十六研究所高级工程师。主要研究方向为晶体生长技术,承担总装备部、国防科工局、工信部、国资委、重庆市以及企事业单位等科技项目。开展了铌酸锂、硅酸铋、锗酸铋、蓝宝石、钇铝石榴石、掺钛蓝宝石、掺铈硅酸钇镥等晶体生长,以及晶体关键性能辅助提升技术开发等工作。曾获重庆市科技进步三等奖(3)、中国电子科技集团公司科技进步奖三等奖(1)等,制定国家和行业标准多项。

Growth and Scintillation Properties of φ100 mm Ca:Ce:LYSO Crystal

WANG Jia, CEN Wei, DING Yuchong, WANG Qiang, ZHANG Zetao

The 26th Insititute of China Electronics Technology Group Corporation, Chongqing 400060, China

Received:2021-08-30 Online:2021-10-15 Published:2021-11-24

摘要/Abstract

摘要： 为了满足具有飞行时间技术特点的正电子发射断层扫描仪(TOF-PET)对光输出高、衰减时间短以及上升时间快的Ce∶LYSO闪烁晶体的需要,本文采用中频感应提拉法生长φ100 mm×100 mm级Ca∶Ce∶LYSO闪烁晶体。晶体整体无色透明、无包裹体。经过紫外可见分光光度计测试,晶体透过率接近理论值,质量较好。将晶体切割研磨抛光后,分别进行脉冲高度谱、衰减时间能谱等测试。在¹³⁷Cs放射源激发下,Ca∶Ce∶LYSO晶体的光输出达到33 962 ph/MeV,能量分辨率为8.6%,衰减时间达到36.70 ns,均优于Ce∶LYSO晶体。通过对晶体轴向及尾部径向取样,相对光输出和能量分辨率不均匀性分别为±2.4%、±9.4%及±1.18%、±6.8%,证明晶体具有较好的均匀性。

关键词: Ca∶Ce∶LYSO, 闪烁晶体, 提拉法, 晶体生长, 闪烁性能, 不均匀性

Abstract: In order to satisfy the requirement of the time-of-flight positron emission tomography (TOF-PET), the Ce:LYSO scintillator should have higher light output, shorter decay time and faster rise time. The transparent and inclusions-free Ca:Ce:LYSO scintillation crystal with size of φ100 mm×100 mm was successfully grown by frequency induction Czochralski method. The transmittance of the prepared crystal tested by UV-Vis spectrophotometer is close to the theoretical value, indicating its excellent quality. After cutting, grinding and polishing, the pulse height spectrum and decay time of the Ca:Ce:LYSO scintillation crystal were tested respectively. The measured light output, energy resolution and decay time are 33 962 ph/MeV, 8.6%, 36.70 ns, respectively,which shows its superior scintillation properties than Ce:LYSO. The inhomogeneity of relative light output and energy resolution of axial sampling are ±2.4% and ±9.4%, and those of the tail-radial sampling are ±1.18% and ±6.8% respectively, which proves the crystal has good uniformity.

Key words: Ca:Ce:LYSO, scintillation crystal, Czochralski method, crystal growth, scintillation property, inhomogeneity

中图分类号:

O734

王佳, 岑伟, 丁雨憧, 王强, 张泽涛. φ100 mm级Ca∶Ce∶LYSO闪烁晶体生长及闪烁性能研究[J]. 人工晶体学报, 2021, 50(10): 1946-1950.

WANG Jia, CEN Wei, DING Yuchong, WANG Qiang, ZHANG Zetao. Growth and Scintillation Properties of φ100 mm Ca:Ce:LYSO Crystal[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2021, 50(10): 1946-1950.

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