磁性多层膜中保护层Ru对磁性层NiFe的影响

The effect of the capping layer Ru to the magnetic layer NiFe in magnetic multilayers

主要研究了不同保护层Ta和Ru对磁性薄膜NiFe的厚度及磁性的影响。通过观察可以看出,NiFe/Ta,NiFe/Ru界面间产生了磁矩为零的部分层即所谓的"死层",其厚度分别为(1.5±0.2)nm,(1.2±0.2)nm(厚度误差在0.2nm范围内)。利用两种保护层时虽然避免不了"死层"现象的出现,但是发现,Ru作为保护层时产生的"死层"厚度比Ta作为保护层时的小。为了进一步证实这一点,我们采用X射线衍射仪及X射线光电子能谱仪对该两种薄膜进行了结构测试和深度剖析,并且运用XPSPeak 4.1拟合软件对获得的Ta4f和Ru3d的高分辨XPS谱进行了计算机拟合分析;结果表明,Ru较Ta更加适合于做保护层,渴望在自旋电子器件上得到应用。

This paper is mainly about the magnetic properties of NiFe thin films when using different cap layers such as Ta,Ru. We observed that there appear dead layers at interface NiFe/Ta and NiFe/Ru. The thickness of dead layers are （1.5±0.2）nm, （1.2±0. 2）nm respectively（experimental error within 0.2nm）. Although it can not be avoided the appearance of the mixing layers namely dead layers while using two kinds of capping layers, but we found that the thickness of dead layer using Ru as capping layer is less than the thickness of dead layer when using Ta as capping layer. For further confirmation of this result, we used X-ray diffraction method, X-ray photo electron spectrum instrument and investigated this two kinds of thin films. Besides we analysed the computer fitting curve of Ta4f and Ru3d high resolution XPS spectrum using XPS Peak 4.1 fitting software. As a result,we confirmed that Ru is good candidate for being capping layer than Ta in spin electron devices.