MAGNETIC ELEMENT WITH IMPROVED OUT-OF-PLANE ANISOTROPY FOR SPINTRONIC APPLICATIONS

摘要

A magnetic element is disclosed wherein first and second interfaces of a free layer with an Hk enhancing layer and tunnel barrier, respectively, produce enhanced surface perpendicular anisotropy to lower switching current or increase thermal stability in a magnetic tunnel junction (MTJ). In an MTJ with a bottom spin valve configuration where the Hk enhancing layer is an oxide, the capping layer contacting the Hk enhancing layer is selected to have a free energy of oxide formation substantially greater than that of the oxide. The free layer may be a single layer or composite comprised of an Fe rich alloy such as Co20Fe60B20. With a thin free layer, the interfacial perpendicular anisotropy may dominate the shape anisotropy to generate a magnetization perpendicular to the planes of the layers.