LaBr_(3):Ce,Sr闪烁晶体的生长及性能研究  

Growth and Properties Study of LaBr_(3)∶Ce,Sr Scintillation Crystal

作　　者：王海丽[1,2] 周南浩 许婉芬 张微 李焕英[3] 韩加红 陈建荣[1,2] WANG Haili;ZHOU Nanhao;XU Wanfen;ZHANG Wei;LI Huanying;HAN Jiahong;CHEN Jianrong(Beijing Sinoma Synthetic Crystals Co.,Ltd.,Beijing 100018,China;Sinoma Synthetic Crystals Co.,Ltd.,Beijing 100018,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 201899,China)

机构地区：[1]北京中材人工晶体研究院有限公司,北京100018 [2]中材人工晶体研究院有限公司,北京100018 [3]中国科学院上海硅酸盐研究所,上海201899

出　　处：《人工晶体学报》2023年第12期2161-2166,共6页Journal of Synthetic Crystals

基　　金：国家重点研发计划(2022YFB3503600)。

摘　　要：采用自发成核坩埚下降法生长了直径25 mm的铈、锶共掺溴化镧(LaBr_(3)∶5%Ce,x%Sr,简称LaBr_(3)∶Ce,Sr,其中x=0.1、0.3、0.5,摩尔分数)闪烁晶体,测试对比了晶体的X射线激发发射光谱、透过光谱和脉冲高度谱等。结果表明,不同Sr^(2+)掺杂浓度的LaBr_(3)∶Ce,Sr晶体在X射线激发下的发射光谱波形基本一致,但相比未掺杂Sr^(2+)的样品,发射峰的峰位发生了明显的红移,随着Sr^(2+)掺杂浓度的增大,发射峰红移程度增大。不同Sr^(2+)掺杂浓度的LaBr_(3)∶Ce,Sr晶体在350~800 nm不存在明显的吸收峰,0.3%和0.5%Sr^(2+)掺杂晶体的透过率有所降低。随着Sr^(2+)掺杂浓度的增大,能量分辨率逐步提高,Sr^(2+)掺杂浓度为0.5%时,LaBr_(3)∶Ce,Sr晶体的能量分辨率最高,达2.99%@662 keV。对尺寸φ25 mm×25 mm的LaBr3∶Ce,0.5%Sr晶体进行了防潮封装,所得晶体封装件的能量分辨率为2.93%@662 keV。In this paper,ϕ25 mm lanthanum bromide scintillation crystals with 5%Ce^(3+)and different Sr^(2+)doping concentrations(0.1%,0.3%,0.5% in molar ratio)were successfully grown by spontaneous nucleation vertical Bridgman method.X-ray excited emission spectra,transmission spectra and pulse height spectra of these crystals were measured.Results show that,the emission spectra waveform of LaBr_(3)∶Ce crystals with different Sr^(2+)doping concentrations is basically consistent under X-ray excitation,and the emission peak shows a significant red shift compared with that of sample without Sr^(2+)doping.With the increase of Sr^(2+)doping concentration,the emission peak of LaBr_(3)∶Ce,Sr crystal shows a slight red shift.There is no obvious absorption peak range from 350 to 800 nm of LaBr_(3)∶Ce,Sr crystals with different Sr^(2+)doping concentrations.Compared with LaBr_(3)∶Ce crystals,transmittance of 0.3%and 0.5%Sr^(2+)doped LaBr_(3)∶Ce crystals decrease.In addition,with the increase of Sr^(2+)doping concentration,the energy resolution of the crystal increases correspondingly.LaBr_(3)∶Ce,0.5%Sr crystal has the highest energy resolution of 2.99%@662 keV.The energy resolution of the encapsulated LaBr_(3)∶Ce,0.5%Sr crystal with size of ϕ25 mm×25 mm is 2.93%@662 keV.

关 键 词：闪烁晶体 LaBr_(3)∶Ce SR 坩埚下降法 X射线激发发射光谱 能量分辨率 封装 

分 类 号：O78[理学—晶体学]