Ultrathin W space layer-enabled thermal stability enhancement in a perpendicular MgO/CoFeB/W/CoFeB/MgO recording frame.

ABSTRACT: Perpendicularly magnetized tunnel junctions (p-MTJs) show promise as reliable candidates for next-generation memory due to their outstanding features. However, several key challenges remain that affect CoFeB/MgO-based p-MTJ performance. One significant issue is the low thermal stability (?) due to the rapid perpendicular magnetic anisotropy (PMA) degradation during annealing at temperatures greater than 300?°C. Thus, the ability to provide thermally robust PMA characteristics is a key steps towards extending the use of these materials. Here, we examine the influence of a W spacer on double MgO/CoFeB/W/CoFeB/MgO frames as a generic alternative layer to ensure thermally-robust PMAs at temperatures up to 425?°C. The thickness-dependent magnetic features of the W layer were evaluated at various annealing temperatures to confirm the presence of strong ferromagnetic interlayer coupling at an optimized 0.55?nm W spacer thickness. Using this W layer we achieved a higher ? of 78 for an approximately circular 20?nm diameter free layer device.

SUBMITTER: Kim JH 

PROVIDER: S-EPMC4653616 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature