Effects of annealing on the magnetic properties and microstructures of Ta/Mo/CoFeB/MgO/Ta films
Effects of annealing on the magnetic properties and microstructures of Ta/Mo/CoFeB/MgO/Ta films
复制标题
退火对Ta/Mo/CoFeB/MgO/Ta薄膜磁性能和微观结构的影响
DOI：
10.1016/j.jallcom.2016.09.027
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发表时间：
2017-01-25
影响因子：
6.2
通讯作者：
Wang, Kang L.
中科院分区：
文献类型：
--
作者：
Li, Minghua;Shi, Hui;Wang, Kang L.
研究了Ta/Mo/CoFeB/MgO/Ta结在350 ℃退火不同时间后垂直磁各向异性（PMA）的演化规律。PMA在短的退火时间后迅速发展，随后缓慢接近饱和。PMA的这种演变伴随着结构变化。随着退火时间的增加，表面粗糙度（R-q）逐渐增加到30分钟;退火时间的进一步增加导致R-q的急剧增加。研究了Ta/Mo/CoFeB/MgO/Ta薄膜的成分和化学状态对薄膜磁各向异性的影响。X射线光电子能谱的结果表明，更多的铁氧化物形成在CoFeB/MgO界面退火1分钟后相比，在沉积的样品，这是至关重要的，以获得PMA。高分辨率透射电子显微镜分析表明，CoFeB和MgO层主要是非晶样品作为沉积和退火后1分钟。退火30 min和60 min后，样品中的CoFeB和MgO层晶化，有利于获得高的PMA。(C)© 2016 Elsevier B. V.版权所有。
We report a study on the evolution of perpendicular magnetic anisotropy (PMA) in Ta/Mo/CoFeB/MgO/Ta junctions annealed at 350 degrees C for different periods of time. The PMA quickly developed after a short annealing time followed by a slow approach to saturation. This evolution of PMA was accompanied by structural changes. The surface roughness (R-q) gradually increased with increasing annealing time to 30 min; further increases in annealing time resulted in a dramatic increase in R-q. The effects of film composition and chemical state on magnetic anisotropy in the as-deposited Ta/Mo/CoFeB/MgO/Ta films and annealed films were studied. The X-ray photoelectron spectroscopy results demonstrated that more Fe oxides were formed at the CoFeB/MgO interface after 1 min of annealing compared to in the as-deposited sample, which is critical to obtain the PMA. High-resolution transmission electron microscopy analysis revealed that the CoFeB and MgO layers are predominantly amorphous in sample as-deposited and after 1min annealing. However, the CoFeB and MgO layers are crystallized in sample after 30 and 60 min annealing, which is beneficial to get high PMA. (C) 2016 Elsevier B.V. All rights reserved.