基于ZnO:In纳米棒阵列的X射线闪烁转换屏制备与性能研究  

Preparation and properties for X-ray scintillation screen based on ZnO:In nanorod arrays

作　　者：李乾利 胡亚华[2] 马逸凡 孙志祥 王敏[1] 刘小林[3] 赵景泰[1] 张志军[1] Li Qian-Li;Hu Ya-Hua;Ma Yi-Fan;Sun Zhi-Xiang;Wang Min;Liu Xiao-Lin;Zhao Jing-Tai;Zhang Zhi-Jun(School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China;College of Nanhu,Jiaxing University,Jiaxing 314001,China;School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]上海大学材料科学与工程学院,上海200444 [2]嘉兴学院南湖学院,嘉兴314001 [3]同济大学物理科学与工程学院,上海200092

出　　处：《物理学报》2020年第10期89-97,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11905122,51772185,51402184,U1832159);中国博士后科学基金(批准号:2019M651469);嘉兴市科技计划项目(批准号:2017AY13015)资助的课题.

摘　　要：为了满足高能物理和核物理领域在探究一些超快物理事件时,对兼顾高时间和高空间分辨的X射线闪烁转换屏的迫切需求,本文利用磁控溅射和水热反应法制备了ZnO:In纳米棒阵列X射线闪烁转换屏,并对其进行氢气氛下的等离子处理优化其闪烁发光性能.X射线激发发射谱显示ZnO:In纳米棒阵列具有395 nm的紫外发光和450-750 nm的可见发光两个发光峰,同时表明氢气氛等离子体处理可显著增强ZnO:In纳米棒阵列的紫外发光,抑制其可见发光.发光衰减时间测量表明,ZnO:In纳米棒阵列紫外发光衰减时间在亚纳秒级,其可见发光衰减时间在纳秒级,两者均可满足高时间分辨的X射线探测需求.在上海同步辐射光源的X射线空间分辨率测试表明,在能量为20 keV的X射线光束辐照下,厚度为12μm的ZnO:In纳米棒阵列作为X射线闪烁转换屏可达到1.5μm的系统空间分辨率.本研究表明利用ZnO:In纳米棒阵列作为X射线闪烁转换屏是实现兼顾高时间和高空间分辨的X射线探测与成像的一种可行方案.X-ray scintillation screens as the core component of X-ray imaging detectors have widespread applications in the medical imaging,security inspection,high energy physics,radiochemistry,and so on.For a long time,the development of X-ray scintillation screen mainly focuses on improving the light yield in order to enhance its detection efficiency.However,a novel tendency has recently emerged for ultrafast time performance of the X-ray imaging detector.The indium doping zinc oxide(ZnO:In) with high radiation hardness,higher light yield(>10000 photons/MeV) and subnanosecond decay time is a promising scintillation material for ultrafast detections.In order to satisfy the requirements of X-ray scintillation screens with ultrafast and high-spatialresolution in the existing and upcoming high energy physics experiments,the ZnO:In nanorod arrays have been prepared on a 100-nm-thick ZnO-seeded substrate by hydrothermal reaction method and then treated by hydrogen plasma in present work.The results of SEM demonstrate the average diameter and length of the ZnO:In nanorods are about 0.5 and 12μm,respectively.The XRD shows the ZnO:In nanorods are highly aligned perpendicular to the substrate along c-axis direction.The X-ray excited luminescence spectra show that two luminescence bands are observed,i.e.an ultraviolet emission peak located at about 395 nm and a visible emission band at 450-750 nm.It is particularly important to point out that hydrogen plasma treatment can enhance the ultraviolet emission of ZnO:In nanorod arrays and suppress its visible emission.The reason is attributed to the formation of shallow donors through hydrogen entering the ZnO and the combination of V_O and O_i.In addition,the fluorescence decay times of the ultraviolet and visible emissions for the ZnO:In nanorod arrays are subnanosecond and nanosecond,respectively,satisfying the demand of the fast X-ray imaging.The spatial resolution of ZnO:In nanorod arrays has been characterized in X-ray imaging beamline at the Shanghai Synchrotron Radiation Facilit

关 键 词：X射线闪烁转换屏 ZnO:In纳米棒阵列 超快衰减时间 高空间分辨率 

分 类 号：TL816.1[核科学技术—核技术及应用]