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

摘要

A MTJ for a spintronic device that is a domain wall motion 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 domain wall motion device, comprising:
(a) a first stack comprising a lower seed layer and a laminated layer formed thereon wherein the first stack has a first width and wherein the seed layer is one or more of Hf, NiCr, and NiFeCr, and the laminated layer has intrinsic PMA and a composition represented by (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; and (b) a second stack with a tunnel barrier/free layer/capping layer configuration and having a second width substantially greater than the first width, the tunnel barrier contacts a top surface of the first stack.