Correlation of Microstructure and Giant Magnetoresistance in Electrodeposited Ni – Cu/Cu Multilayers
Correlation of Microstructure and Giant Magnetoresistance in Electrodeposited Ni – Cu/Cu Multilayers
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电沉积 Ni-Cu/Cu 多层膜中微观结构与巨磁阻的相关性
DOI：
10.3139/ijmr-1997-0147
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发表时间：
1997
期刊：
影响因子：
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通讯作者：
I. Bakonyi
中科院分区：
文献类型：
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作者：
Á. Cziráki;I. Gerőcs;B. Fogarassy;Birgit Arnold;M. Reibold;K. Wetzig;E. Toth;I. Bakonyi
在脉冲电镀Ni81Cu19/Cu多层膜中观察到了巨磁电阻效应，当Ni-Cu层厚度在2~3 nm时，巨磁电阻效应的最大值约为2%。透射电子显微镜观察到多层膜呈柱状生长。具有最大巨磁电阻的多层膜的柱宽(晶粒度)最大。还可以确定多层平面相对于衬底平面通常倾斜角度，这取决于化学调制波长。这无疑引起了电流垂直于平面的巨磁电阻贡献，为巨磁电阻随厚度曲线的最大值的位置提供了一个合理的解释。Ni-Cu层和Cu层之间的晶格常数失配导致了相当大的应力松弛，除了孪晶和位错结构的形成外，还由于诱导的周期性晶格扭曲(结构调制)，这种周期性晶格扭曲与化学调制在每个方向上都不完全一致。
Abstract Giant magnetoresistance (GMR) was observed in pulse-plated Ni81Cu19/Cu multilayers with a maximum GMR value of about 2 % for Ni – Cu layer thicknesses around 2 to 3 nm. A columnar growth of the multilayers was detected by transmission electron microscopy. The column width (grain size) was the largest for multilayers with the maximum GMR. It could also be established that the multilayer planes are often inclined at angle, which depends on the chemical modulation wavelength, with respect to the substrate plane. This definitely gives rise to a current-perpendicular-to-plane contribution to the GMR, offering a plausible explanation for the location of the maximum of the GMR vs thickness curve. The lattice constant mismatch between the Ni – Cu and Cu layers gives rise to considerable stresses which are relaxed, besides the formation of twinning and dislocation structures, also by an induced periodic lattice distortion (structural modulation) not completely coinciding with the chemical modulation in every direction.