Changes in the layer roughness and crystallography during the annealing of CoFeB/MgO/CoFeB magnetic tunnel junctions
Changes in the layer roughness and crystallography during the annealing of CoFeB/MgO/CoFeB magnetic tunnel junctions
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DOI：
10.1063/1.3081652
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发表时间：
2009-03-15
影响因子：
3.2
通讯作者：
Marrows, C. H.
中科院分区：
文献类型：
--
作者：
Anderson, G. I. R.;Wei, H. -X.;Marrows, C. H.
在溅射CoFeB/MgO/CoFeB磁性隧道结（MTJs）中，退火是实现大隧道磁电阻（TMR）值的必要条件。在这项研究中，三种互补的技术被用来研究结微观结构的变化。在325℃退火1 h后，沉积的TMR为5%，上升到101%，对应于隧道自旋极化从16%上升到58%。软x射线共振磁散射显示MTJ自由层的磁性界面变得粗糙，透射电镜证实，CoFeB和MgO也转变为晶格匹配的多晶形式。
Annealing is necessary to achieve giant tunneling magnetoresistance (TMR) values in sputtered CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs). In this study three complementary techniques were used to study the resulting changes in junction microstructure. The as-deposited TMR was modest, 5%, but rose to 101% after annealing at 325 degrees C for 1 h, corresponding to the tunneling spin polarization rising from 16% to 58%. Soft x-ray resonant magnetic scattering showed a roughening of the magnetic interfaces of the MTJ free layer, confirmed by transmission electron microscopy, which also showed the changes in the CoFeB and MgO to a lattice-matched polycrystalline form.