衬底层对Fe_(65)Co_(35)合金薄膜结构与磁性的影响  

Effects of underlayer on structures and magnetic properties of Fe_(65)Co_(35) alloy films

作　　者：韩泽宇 宋乘吉 周杰 郑富 Han Ze-Yu;Song Cheng-Ji;Zhou Jie;Zheng Fu(School of Physics and Electronic-Electrical Engineering,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学物理与电子电气工程学院,银川750021

出　　处：《物理学报》2022年第15期239-247,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11964027)资助的课题。

摘　　要：采用磁控溅射法制备了具有不同衬底层(Cu,Co和Ni_(80)Fe_(20))的FeFe_(65)Co_(35)双层合金薄膜.研究了不同衬底材料以及NiFe衬底层厚度对FeCo合金薄膜结构与磁性的影响.研究结果表明:衬底层的引入可以增加薄膜的面内单轴各向异性,且薄膜的软磁性能显著提升,获得良好软磁性的原因归结为晶粒的细化、层间的偶极相互作用以及表面粗糙度的降低,并且对于相同厚度的不同衬底层,NiFe衬底层对FeCo薄膜软磁性能的提升最为明显;通过改变NiFe衬底层厚度,实现了对薄膜各向异性的调控,NiFe/FeCo表现出良好的高频响应和低的阻尼系数,同时较小的薄膜厚度能够减小涡流损耗,因此,促进了其在高频微波磁性器件方面的应用.Fe_(100-x) Co_(x)(x = 30–40) alloys have the highest saturation magnetizations,4πM_(s) ≥ 24 kG(1 G = 10^(–4) T).Therefore,FeCo thin flms have been widely used in microwave magnetic devices.However,the as-deposited FeCo film has a large coercivity,which is attributed to the large saturation magnetostriction and high magnetocrystalline anisotropy.On the basis of maintaining high saturation magnetization,adding an appropriate underlayer is a simple and effective method to reduce the coercivity of the film and facilitate the magnetic fieldinduced in-plane uniaxial magnetic anisotropy.Since these kinds of films are used in a high-frequency environment,the eddy current loss in GHz band must be considered.For a certain film material,the thinner the film,the lower the eddy current loss is.However,at present,the thickness of ferromagnetic layer is generally tens of nanometers or even hundreds of nanometers,which will not help to suppress the eddy current loss at high frequency.In the present study,to obtain FeCo films with good soft magnetic properties and excellent high-frequency characteristics,Fe_(65)Co_(35) alloy films with a thickness of 13 nm and different underlayers(Cu,Co and Ni_(80)Fe_(20)) are prepared by magnetron sputtering.The effects of different underlayer materials and different NiFe underlayer thickness values on the structures and magnetic properties of FeCo films are studied.The results show that the introduction of underlayers can increase the in-plane uniaxial magnetic anisotropies of films,and the soft magnetic properties of films are significantly improved.The reason why the good soft magnetic properties can be achieved is attributed to the grain refinement,the dipolar interaction between layers,and the reduction of surface roughness.For different underlayer materials with the same thickness,NiFe underlayer can obviously improve the soft magnetic properties of FeCo films:the covercivity of easy axis is 23 Oe.By changing the thickness of NiFe underlayer,the dynamic magnetic properties of films

关 键 词：FeCo合金薄膜 衬底层 软磁性能 高频特性 

分 类 号：TB383.2[一般工业技术—材料科学与工程]