Acceleration of ordering transformation of a new Fe2(Mn,Cr)Si Heusler-alloy film by very high frequency plasma irradiation process during radio frequency sputter deposition
Acceleration of ordering transformation of a new Fe2(Mn,Cr)Si Heusler-alloy film by very high frequency plasma irradiation process during radio frequency sputter deposition
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DOI：
10.1063/1.3562198
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发表时间：
2011-04-01
影响因子：
3.2
通讯作者：
Ishida, S.
中科院分区：
文献类型：
--
作者：
Yoshimura, S.;Kobayashi, H.;Ishida, S.
提出了一种新的赫斯勒合金Fe - 2(Mn, Cr)Si，它可能具有高自旋极化率（P）和高阻尼常数（α），以便在具有电流垂直于平面（CPP）巨磁电阻（GMR）多层膜的磁读头中获得高磁阻比和低自旋扭矩噪声。研究了在射频（RF）溅射沉积过程中的甚高频（VHF）等离子体辐照工艺，以在较低的热处理温度下形成赫斯勒合金薄膜的高度有序结构。主要结果如下：（1）根据态密度（DOS）计算，具有L2(1)结构的Fe - 2(Mn0.5Cr0.5)Si的P和磁矩分别估计为0.99和2.49 μB/原子单位（f.u.），并且与Co2MnSi的情况相比，α也估计更大。（2）通过使用优化条件的VHF等离子体辐照工艺，Fe - 2(Mn0.6Cr0.4)Si薄膜的有序化（至少B2结构）温度从500℃降低到300℃。（3）通过使用VHF等离子体辐照工艺，Fe - 2(Mn0.6Cr0.4)Si薄膜的表面粗糙度也从1.7nm降低到0.5nm。发现Fe - 2(Mn, Cr)Si赫斯勒合金以及优化条件的VHF等离子体辐照工艺似乎可应用于制造具有CPP - GMR器件的高性能磁读头。（C）2011美国物理学会。[doi: 10.1063/1.3562198]
A new Heusler alloy, Fe-2(Mn, Cr) Si, that is likely to have high spin polarization (P) and high damping constant (alpha) was proposed to obtain high magneto-resistance ratio and low spin torque noise in a magnetic read head with a current-perpendicular-to-plane (CPP) giant magneto-resistance (GMR) multilayer. A very high frequency (VHF) plasma irradiation process during radio frequency (RF) sputter deposition was investigated to form the highly ordered structure of the Heusler alloy film with low thermal treatment temperature. The main results are as follows: (1) P and magnetic moment of Fe-2(Mn0.5Cr0.5) Si with an L2(1) structure were estimated at 0.99 and 2.49 mu B/f.u., respectively, and alpha was also estimated to be larger compared with the case of Co2MnSi, according to density of states (DOS) calculations. (2) The ordering (at least B2 structure) temperature of Fe-2(Mn0.6Cr0.4) Si film decreased from 500 to 300 degrees C by using the VHF plasma irradiation process with optimized condition. (3) The surface roughness of Fe-2(Mn0.6Cr0.4) Si film also reduced from 1.7 to 0.5 nm by using the VHF plasma irradiation process. It is found that the Fe-2(Mn, Cr) Si Heusler alloy and the VHF plasma irradiation process with optimized condition seems to be applicable for fabrication of high-performance magnetic read head with CPP-GMR device. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3562198]