薄膜高频磁阻抗效应及其应用

本文介绍了Ｆｅ－Ｎｉ软磁薄膜高频磁阻抗效应及在磁传感技术中的应用，分析了讨论了获得高灵敏度磁传感的途径，磁性薄膜厚度的一般控制在４００ｎｍ以上抑制Ｎｅｅｌ壁的出现，为了提高电压输出变化灵敏度，需要沿被测场方向加向Ｏｅ的偏磁场并使高频磁场形成闭合回路，感生各向异性通过在溅射薄膜过程中加几百Ｏｅ平行于膜的直流磁场获得，与各向异性磁阻效应和巨磁阻效应相比，高频磁阻抗效应传感技术灵敏度高，无巴克豪森噪声，

High Frequency Magnetic Impedance Effect in Film and its Applications

A novel high freguency magnetic impedance (HFMI) effect in soft thin film is introduced,with its applications.It is discussed how to obtain high sensitivity.The thickness of magnetic film should be thicker than 400nm in order to surpress Neel walls.Several Oe bias magnetic field needs to be applied along detected field to get high output voltage change and a closure magnetic circuit for high freguency field is needed.An uniaxial anisotropic magnetic field is induced by applying a constant magnetic field of several hundred Oe to the film surface during sputtering.Compared with anisotropic magnetoresistance effect and giant magnetoresistance effect,the sensitivity using HFMI technique is much higher at room temperature and in low magnetic field.