摘要
采用一种新的种子层材料 :(Ni0 81 Fe0 1 9) 1 -xCrx,通过改变种子层中Cr原子的含量 ,使得在其上生长的NiFe FeMn双层膜的织构和晶粒尺寸产生极大的差异 ,系统研究了NiFe FeMn双层膜中FeMn晶粒尺寸和织构对交换偏置的影响 .实验结果表明 ,在FeMn的γ相 (111)织构较好的前提下 ,交换偏置场的大小与织构的差异没有关系 ;FeMn的晶粒尺寸对交换偏置场有很大影响 ,较小的反铁磁层晶粒对交换偏置场有利 ,过大的反铁磁层晶粒不利于交换偏置场 .将 (Ni0 81 Fe0 1 9) 0 5Cr0 5与传统的种子层材料Ta进行了对比 ,发现前者具有很多优点 。
A thin (Ni-0.81 Fe-0.19)(1-x)Cr-x seed layer was employed to alter the crystallinity and grain size of NiFe/FeMn bilayers through varying Cr content, and the effect of the, crystallinity and grain size on the exchange bias of NiFe/FeMn has been investigated. It has been found that, the interface of NiFe/FeMn is quite smooth for the films grown on the seed layer of (Ni-0.81 Fe-0.19)(1-x) Cr-x , and the difference of the crystallinity of FeMn layer is not the cause of the variation in the exchange bias field once a well textured FeMn layer is achieved. On the other hand, the exchange bias field depends strongly on the grain size of the FeMn layer, i.e. the exchange bias decreases rapidly with the increase of FeMn grain size, which is. consistent with Neel's theoretical prediction. Finally (Ni0.81Fe0.19)(0.5)Cr-0.5 has been compared with Ta as the seed layer of NiFe/FeMn films from the aspects of exchange bias, thermal stability and electric resistivity. It has been shown that the former has more merits, and could be a promising seed layer in the future.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2002年第12期2849-2853,共5页
Acta Physica Sinica
基金
国家自然科学基金重大项目 (批准号 :19890 3 10 )资助的课题~~
