Epitaxial Co2Cr0.6Fe0.4Al thin films and magnetic tunnelling junctions
Epitaxial Co2Cr0.6Fe0.4Al thin films and magnetic tunnelling junctions
复制标题
外延Co2Cr0.6Fe0.4Al薄膜和磁隧道结
DOI：
--
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
H. Adrian
中科院分区：
文献类型：
--
作者：
A. Conca;M. Jourdan;H. Adrian
通过直流磁控溅射在不同的基底和缓冲层上沉积了理论预测的半金属Co2Cr0.6Fe0.4Al的外延薄膜。通过 X 射线和电子束衍射 (RHEED) 对样品进行了表征，证明 Heusler 化合物为 B2 有序，Co 位点上只有一小部分无序。制备了具有Co2Cr0.6Fe0.4Al电极、AlOx势垒和Co对电极的磁隧道结。根据 Jullière 模型，推导出 T = 4 K 时 Co2Cr0.6Fe0.4Al 的自旋极化率为 54%。研究了 Heusler 电极的退火温度与隧道磁阻效应大小之间的关系，并在基于原位扫描隧道显微镜 (STM) 和 RHEED 研究的形态和表面有序框架中讨论了结果。
Epitaxial thin films of the theoretically predicted half metal Co2Cr0.6Fe0.4Al were deposited by dc magnetron sputtering on different substrates and buffer layers. The samples were characterized by x-ray and electron beam diffraction (RHEED) demonstrating the B2 order of the Heusler compound with only a small fraction of disorder on the Co sites. Magnetic tunnelling junctions with Co2Cr0.6Fe0.4Al electrode, AlOx barrier and Co counter electrode were prepared. From the Jullière model a spin polarization of Co2Cr0.6Fe0.4Al of 54% at T = 4 K was deduced. The relation between the annealing temperature of the Heusler electrodes and the magnitude of the tunnelling magnetoresistance effect was investigated and the results are discussed in the framework of morphology and surface order based on in situ scanning tunnelling microscopy (STM) and RHEED investigations.