Perpendicular magnetic anisotropy BCC multilayers

Patent metadata

Field	Value
Publication number	US-9773971-B2
Application number	US-201615254107-A
Country	US
Kind code	B2
Filing date	Sep 1, 2016
Priority date	Mar 26, 2015
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A magnetic material includes a cobalt layer between opposing iron layers. The iron layers include iron and are body-centered cubic (BCC), the cobalt layer comprises cobalt and is BCC or amorphous, and the magnetic material has a perpendicular magnetic anisotropy (PMA).

First claim

What is claimed is:

1. A method of making a magnetic material, the method comprising:
forming a cobalt layer on a first iron layer; and
forming a second iron layer on the cobalt layer;
wherein the first and second iron layers comprise iron and are BCC, the cobalt layer comprises cobalt and is BCC or amorphous, and the magnetic material has a PMA;
wherein the magnetic material forms a portion of a spin torque magnetic random access memory chip.

2. The method of claim 1 , further comprising forming a tunnel barrier layer on the first or second iron layer.

3. The method of claim 1 , wherein the first iron layer comprises an iron alloy.

4. The method of claim 1 , wherein the cobalt layer is a cobalt alloy.

5. The method of claim 1 , wherein the magnetic material forms a portion of a magnetic tunnel junction.

6. The method of claim 1 , wherein the magnetic material forms a magnetic free layer of a magnetic tunnel junction.

7. The method of claim 1 , wherein the magnetic material forms a magnetic fixed layer of a magnetic tunnel junction.

8. The method of claim 1 , wherein iron is present in an amount of at least 50 atomic % (at. %) in the magnetic material.

9. The method of claim 1 , wherein cobalt is present in an amount of at least 30 at. % in the magnetic material.

10. The method of claim 1 , further comprising forming a magnesium oxide layer on a surface of the magnetic material.

11. The method of claim 1 , further comprising forming a tunnel barrier layer on the first iron layer or the second iron layer.

12. The method of claim 2 , wherein the tunnel barrier layer comprises magnesium oxide.

13. The method of claim 2 , wherein the tunnel barrier is formed on an iron-rich dusting layer.

14. The method of claim 3 , wherein the second iron layer comprises an iron alloy.

15. The method of claim 6 , wherein the magnetic free layer has a variable magnetization direction.

16. The method of claim 7 , wherein the magnetic fixed layer has an invariable magnetization direction.

17. The method of claim 10 , wherein the magnesium oxide layer contacts the second iron layer.

18. The method of claim 17 , further comprising forming a dusting layer between the magnesium oxide layer and the second iron layer.

19. The method of claim 18 , wherein the dusting layer comprises iron.

Assignees

• IBM

Inventors

• Hu Guohan
• Worledge Daniel C

Classifications

• H01F10/3286 Primary

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

• G11C11/161

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

• H01F41/32

  for applying conductive, insulating or magnetic material on a magnetic film {, specially adapted for a thin magnetic film} · CPC title

• H01F10/3254

  the spacer being semiconducting or insulating, e.g. for spin tunnel junction [STJ] · CPC title

• H01F10/14

  containing iron or nickel ({H01F10/126} , H01F10/13, H01F10/16 take precedence) · CPC title