Tb/FeCo多层膜的垂直交换偏置效应  

Perpendicular Exchange Bias Effect in Tb/FeCo Multilayer Films

作　　者：童六牛[1] 李晗飞[1] 卜立一 高成[1] 李婷婷[1] 邓鹏[1] TONG Liuniu LI Hanfei BU Liyi GAO Cheng LI Tingting DENG Peng(School of Materials Science and Engineering, Anhui University ofTechnology,Ma＇anshan 243032,Chin)

机构地区：[1]安徽工业大学材料科学与工程学院,安徽马鞍山243032

出　　处：《安徽工业大学学报（自然科学版）》2017年第1期28-32,共5页Journal of Anhui University of Technology（Natural Science）

基　　金：安徽省教育厅重点项目(KJ2011A052);国家自然科学基金项目(51671001)

摘　　要：采用磁控溅射方法,制备结构为Glass/Cu(60 nm)/[Tb(tTb=1.5,3.0 nm)/FeCo(1.5 nm)]5/Ta(10 nm)的两种不同Tb子层厚度的多层膜。采用X射线衍射分析仪、原子力和磁力显微镜、振动样品磁强计对样品的晶体结构、磁畴结构和室温磁性质进行表征,研究该多层膜系统的垂直磁各向异性和垂直交换偏置效应。X射线衍射分析表明,多层膜中Tb/FeCo界面主要呈非晶或纳米晶态。磁力显微镜结果显示,制备态薄膜均呈现迷宫状条纹磁畴结构。室温磁性测量表明,薄膜的易磁化方向都垂直膜面,垂直矫顽力分别为122和351 kA/m。在由这两种多层膜组合而成的Glass/Cu(60 nm)/[Tb(1.5 nm)/FeCo(1.5 nm)]2/[Tb(3.0 nm)/FeCo(1.5 nm)]5/Ta(10 nm)软磁/硬磁型多层膜中发现交换偏置场为20 kA/m的垂直交换偏置效应,这一效应的发现对Tb/FeCo多层膜在现代超快磁存储器中的应用具有重要意义。Two kinds of Glass/ Cu（60 nm）/[ Tb（？ Th = 1.5, 3.0 nm）/ FeCo（1.5 nm）] s/ Ta（10 nm） multilayer films were fabricated by magnetron sputtering method. The crystal structure, magnetic domain structure and room tempera-ture （ RT） magnetic properties of the samples were characterized with X-ray diffraction, atomic force and magnetic force microscopy, and vibrating sample magne-mtoeter. The perpendicular magnetic anisotropy and perpendicular exchange bias effects of the multilayer films were studied. X-ray diffraction analysis show that the Tb/FeCo inter-faces in the multilayer films are mainly in amorphous or nanocrystalline structure. The magnetic force microscope images exhibit a disordered labyrinthine stripe domain structure for all of the as- deposited films. The magnetic measurements at RT show that all the samples exhibit out-of-plane anisotropy with the perpendicular coercive fields of 122 and 351 kA/m for the Glass/ Cu（60 nm）/[ Tb（ trb ）/ FeCo（1.5 nm）]5/ Ta（10 nm） multilayers with tTb = 1.5 and 3.0 nm, respectively. A robust perpendicular exchange bias （ P-EB） effect with an exchange bias field of 20 kA/m is observed in a prototypical soft/hard exchange coupled spin valve structure consisting of Glass/ Cu（60 nm）/[ Tb（1.5 nm）/ FeCo（1.5 nm）] 2/[ Tb（3.0 nm）/ FeCo（1.5 nm）] 5 / Ta（10 nm） multilayers. Such a robust P-EB effect obtained in Tb/FeCo based multilayer films may be of crucial importance for applications in modern ultra-fast storage media.

关 键 词：Tb/FeCo多层膜 条纹磁畴 垂直交换偏置效应 

分 类 号：TM271[一般工业技术—材料科学与工程]