Fe离子注入ZnO生成超顺磁纳米颗粒  

Superparamagnetic nanoparticles formed in Fe-implanted ZnO

作　　者：潘峰[1,2] 丁斌峰[1,3] 法涛[1] 成枫锋[1] 周生强[1] 姚淑德[1] 

机构地区：[1]北京大学核物理与核技术国家重点实验室,北京100871 [2]陕西理工学院物理系,汉中723001 [3]廊坊师范学院物理与电子信息学院,廊坊065000

出　　处：《物理学报》2011年第10期736-741,共6页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2010CB832904);国家自然科学基金(批准号:10875007;11005005)资助的课题~~

摘　　要：过渡族元素掺杂ZnO生成稀磁半导体,成为近期国际材料科学研究的热点.在本文中,研究Fe离子注入ZnO单晶的结构和磁性变化,目标是建立磁性和结构的对应关系,澄清铁磁性的来源.采用卢瑟福背散射/沟道技术(RBS/Channelling)、同步辐射X射线衍射(SR-XRD)和超导量子干涉仪(SQUID),研究注入温度和退火对样品的晶格损伤、结构及磁性的影响.研究表明:样品注入区损伤随注入温度升高而降低;低温253K注入样品中,SR-XRD未检测到新相,Fe离子分布于Zn位,ZnO(0002)峰右侧肩峰可能属于Zn1-xFexO,5K下测试样品不具有铁磁性;623K注入和823K真空退火(253K注入)样品中形成α和γ相金属Fe,5K下样品具有明显的剩磁和矫顽力,零场冷却和场冷却(ZFC/FC)曲线和300K下的磁滞回线显示纳米Fe颗粒具有超顺磁性.Fe离子注入ZnO的磁性源于第二相α-Fe和γ-Fe.Due to its potential application to diluted magnetic oxides,transition metal doped ZnO has been under intensive investigation.We present a correlation between the structural and the magnetic properties of Fe implanted ZnO bulk crystals.Crystalline damage recovery,structural and magnetic properties are studied by Rutherford backscattering spectrometry and channelling（RBS/C）,synchrotron radiation X-ray diffraction（SR-XRD）,and superconducting quantum interference device magnetometer（SQUID）,respectively.The 623 K Fe ion implantation and the high vacuum annealing at 823 K lead to the formation of secondary phase α-Fe and γ-Fe nanoparticles.The discrepancy between the zero-field cooling and the field cooling curves further indicates that Fe-implanted ZnO is superparamagnetic and the observed ferromagnetism originates from the Fe nanoparticles.

关 键 词：离子注入 ZNO 同步辐射X射线衍射 超顺磁性 

分 类 号：TB383.1[一般工业技术—材料科学与工程]