CoFeB/MgO不连续多层纳米软磁薄膜微波电磁特性  

Electromagnetic and microwave properties of discontinuous CoFeB/MgO soft magnetic multilayer films

作　　者：马强[1] 江建军[1] 别少伟[1] 杜刚[1] 冯则坤[1] 何华辉[1] 

机构地区：[1]华中科技大学电子科学与技术系,武汉430074

出　　处：《物理学报》2008年第10期6577-6581,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50771047和50371029);新世纪优秀人才支持计划(批准号:NCET20420702);湖北省杰出青年基金计划(批准号:2005ABB002)资助的课题~~

摘　　要：采用直流/射频磁控溅射方法和不连续多层交替沉积工艺,制备了CoFeB/MgO系列纳米不连续多层薄膜,研究了微波频段下的电磁性能.结果表明,通过调整CoFeB合金相和MgO介质相的相对含量可有效调控薄膜的微结构和电磁性能,且在[Co64Fe24B12(0.7 nm)/MgO(0.4 nm)]40薄膜中获得了优良的微波软磁性能和高电阻率,其饱和磁化强度1.3 T,难轴矫顽力130 A/m,电阻率3.4 mΩ.cm,且共振频率高达2.1 GHz,磁导率实部μ′和虚部μ″在1.59 GHz处均高于240,并且在0.9—2 GHz宽频带范围同时大于100.该薄膜可用于微波吸收材料和电磁兼容的设计中.A series of discontinuous muhilayers of CoFeB-MgO was fabricated by using DC/RF magnetron sputtering, and the electromagnetic and microwave properties were investigated. The results show that the mierostructure and electromagnetic properties of the CoFeB-MgO discontinuous muhilayer films can be altered by varying the relative content of the magnetic CoFeB phase and the insulating MgO phase. High performance microwave soft magnetic properties along with high resistivity are achievedin the discontinuous [Co64 Fe24 B12 （0.7 nm）/MgO（0.4 nm）]40 multilayer film. This film has the saturation magnetization of 1.3 T, hard axis coercivity of 130 A/m, and resistivity of 3.4 mΩ·cm. Moreover, the resonance frequency is about 2.1 GHz for this film. Both the real part μ′ and the imaginary part μ″ of the measured permeability are larger than 240 at 1.59 GHz and are both larger than 100 from 0.9 GHz to 2 GHz. So this film has potential for serving as the microwave absorbers and electromagnetic compatibility materials in the GHz frequency range.

关 键 词：纳米磁性颗粒膜 磁导率频谱 电磁性能 吸波材料 

分 类 号：O484.4[理学—固体物理]