Spin torque MRAM having perpendicular magnetization with oxide interface

Patent metadata

Field	Value
Publication number	US-9087543-B2
Application number	US-201313911609-A
Country	US
Kind code	B2
Filing date	Jun 6, 2013
Priority date	Jun 6, 2013
Publication date	Jul 21, 2015
Grant date	Jul 21, 2015

Abstract

A mechanism is provided for a structure with perpendicular magnetic anisotropy. A bottom oxide layer is disposed, and a magnetic layer is disposed adjacent to the bottom oxide layer. The magnetic layer includes iron and is magnetized perpendicularly to a plane of the magnetic layer. A top oxide layer is disposed adjacent to the magnetic layer.

First claim

What is claimed is:

1. A spin torque MRAM structure with perpendicular magnetic anisotropy, comprising:
a bottom oxide layer directly on a seed layer;
a magnetic layer disposed directly on top of the bottom oxide layer, wherein the magnetic layer includes iron and is magnetized perpendicularly to a longitudinal plane of the magnetic layer, and wherein the bottom oxide layer includes at least one of AlOx, HfOx, CuOx, RuOx, SiOx, WOx, BOx, CaOx, ScOx, ZnOx, CrOx, MnOx, and combinations thereof;
a top oxide layer disposed directly on top of the magnetic layer, wherein the top oxide layer includes at least one of CuOx, WOx, BOx, CaOx, ScOx, ZnOx, CrOx, MnOx, and combinations thereof, and wherein a reference magnetic layer comprises a sandwich of the bottom oxide layer, the magnetic layer, and the top oxide layer;
a free magnetic layer disposed directly on top of the top oxide layer; and
a cap layer disposed on top of the free magnetic layer.

2. The structure of claim 1 , wherein the bottom oxide layer includes MgO.

3. The structure of claim 1 , wherein the top oxide layer includes MgO.

4. The structure of claim 1 , wherein the magnetic layer is CoFeB.

5. The structure of claim 1 , wherein the magnetic layer includes CoFeBTa.

6. The structure of claim 1 , wherein the free layer in the spin torque MRAM is formed by the top oxide layer, another magnetic layer, and a second top oxide layer.

Assignees

• IBM

Inventors

• Hu Guohan
• Worledge Daniel

Classifications

• G11B5/8404 Primary

  manufacturing base layers · CPC title

• H01F10/329

  Spin-exchange coupled multilayers wherein the magnetisation of the free layer is switched by a spin-polarised current, e.g. spin torque effect · CPC title

• G11C11/161

  details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell · CPC title

• H01F10/3286

  Spin-exchange coupled multilayers having at least one layer with perpendicular magnetic anisotropy · CPC title

• H01F10/3259

  Spin-exchange-coupled multilayers comprising at least a nanooxide layer [NOL], e.g. with a NOL spacer · CPC title