Method and system for providing a bottom pinned layer in a perpendicular magnetic junction usable in spin transfer torque magnetic random access memory applications

摘要

A magnetic junction and method for providing the magnetic junction are described. The magnetic junction includes free and pinned layers separated by a nonmagnetic spacer layer. The free layer is switchable between stable magnetic states when a write current is passed through the magnetic junction. The pinned layer has a perpendicular magnetic anisotropy (PMA) energy greater than its out-of-plane demagnetization energy. Providing the pinned layer includes providing a bulk PMA (B-PMA) layer, providing an interfacial PMA (I-PMA) layer on the B-PMA layer and then providing a sacrificial layer that is a sink for a constituent of the first I-PMA layer. An anneal is then performed. The sacrificial layer and part of the first I-PMA layer are removed after the anneal. Additional I-PMA layer(s) are provided after the removing. A remaining part of the first I-PMA layer and the additional I-PMA layer(s) have a thickness of not more than twenty Angstroms.