Article ID Journal Published Year Pages File Type
5461498 Journal of Alloys and Compounds 2017 6 Pages PDF
Abstract
We report a study on the evolution of perpendicular magnetic anisotropy (PMA) in Ta/Mo/CoFeB/MgO/Ta junctions annealed at 350 °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 (Rq) gradually increased with increasing annealing time to 30 min; further increases in annealing time resulted in a dramatic increase in Rq. 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.
Related Topics
Physical Sciences and Engineering Materials Science Metals and Alloys
Authors
, , , , , , , , ,