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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.
In the present paper, the structure and magnetic changes of Fe single-crystal ZnO single crystal have been studied, and the goal is to establish the corresponding relationship between magnetic and structure, to clarify the ferromagnetism The RTS / Channelling, SR-XRD and SQUID were used to study the effects of implantation temperature and annealing on the crystal lattice of samples , Structure and magnetism. The results show that the damage of sample injection zone decreases with the increase of injection temperature. No new phase is detected by SR-XRD, The side shoulders may belong to Zn1-xFexO, and the test samples at 5K do not have ferromagnetism. The α and γ phase metal Fe is formed in the samples annealed at 623K and 823K vacuum annealing (253K injection). The samples at 5K show significant remanence and coercivity , ZFC / FC curve and hysteresis loop at 300K show the superparamagnetism of Fe nanoparticles.The magnetic field of Fe ion-implanted ZnO originates from the second phase α-Fe and γ-Fe.