CoFeB/MgO界面垂直磁各向异性的影响因素研究

Study of the factors influencing the perpendicular magnetic anisotropy at CoFeB/MgO interface

回顾了近年来国际上关于提高CoFeB/MgO界面垂直磁各向异性的研究,从非磁/CoFeB/MgO多层膜结构(各层膜的厚度、堆积次序、周期数、铁磁/氧化物界面粗糙度和铁磁层,氧化物层及缓冲层的结晶状态)、成分(铁磁层的成分、缓冲层的材料、保护层的材料)及材料工艺(热处理温度、外加电场和外加应力)等方面考察了CoFeB/MgO异质结中界面垂直磁各向异性的影响因素。理解CoFeB/MgO界面垂直磁各向异性的影响因素有助于更好地理解非磁/CoFeB/MgO磁性多层膜中垂直磁各向异性来源的深层物理机制以及通过优化材料结构和工艺进而优化非磁/CoFeB/MgO磁性多层膜的垂直磁各向异性。

In this paper,the reports about improving the perpendicular magnetic anisotropy at the CoFeB/MgO interface in recent years were reviewed.The influence factors of the perpendicular magnetic anisotropy at the CoFeB/MgO interface were summarized from the aspects of multilayer structure（thickness of each layer,stack sequence,periodic numbers,interfacial roughness,and the degree of crystallization in the buffer,layer,ferromagnetic layer,or oxide layer）,multilayer composition（composition of the ferromagnetic layer,and material types of the buffer layer and capping layer）,and material process（annealing process,applied electric field and applied strain）.Understanding the influence factors of the perpendicular magnetic anisotropy at the CoFeB/MgO interface is helpful to better understand the source of perpendicular magnetic anisotropy in the nonmagnetic metal/CoFeB/MgO multilayers in the deep physical mechanism and optimize the perpendicular magnetic anisotropy by using proper structure and technology.