Co/Ni Multilayers with Improved Out-of-Plane Anisotropy for Magnetic Device Applications

摘要

A MTJ for a spintronic device is disclosed and includes a thin seed layer that enhances perpendicular magnetic anisotropy (PMA) in an overlying laminated layer with a (Co/X)n or (CoX)n composition where n is from 2 to 30, X is one of V, Rh, Ir, Os, Ru, Au, Cr, Mo, Cu, Ti, Re, Mg, or Si, and CoX is a disordered alloy. The seed layer is preferably NiCr, NiFeCr, Hf, or a composite thereof with a thickness from 10 to 100 Angstroms. Furthermore, a magnetic layer such as CoFeB may be formed between the laminated layer and a tunnel barrier layer to serve as a transitional layer between a (111) laminate and (100) MgO tunnel barrier. The laminated layer may be used as a reference layer, dipole layer, or free layer in a MTJ. Annealing between 300° C. and 400° C. may be used to further enhance PMA in the laminated layer.

主权项

1. A magnetic tunnel junction (MTJ), comprising:
(a) a seed layer formed on a substrate; (b) a free layer comprising a laminated stack that contacts a top surface of the seed layer, the laminated layer has intrinsic perpendicular magnetic anisotropy (PMA) and comprises a (Co/X)n or (CoX)n structure wherein X is one of V, Rh, Ir, Os, Ru, Au, Cr, Mo, Cu, Ti, Re, Mg, and Si, CoX is a disordered alloy, and n is the number of laminates in the stack; (c) a tunnel barrier layer formed on the free layer; (d) a reference layer formed on the tunnel barrier layer; and (e) and a capping layer formed on the reference layer.