Magnetic memory element incorporating dual perpendicular enhancement layers

Patent metadata

Field	Value
Publication number	US-11417836-B2
Application number	US-202117156562-A
Country	US
Kind code	B2
Filing date	Jan 23, 2021
Priority date	Sep 14, 2010
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

The present invention is directed to a magnetic memory element including a magnetic free layer structure incorporating three magnetic free layers separated by two perpendicular enhancement layers (PELs) and having a variable magnetization direction substantially perpendicular to layer planes thereof; an insulating tunnel junction layer formed adjacent to the magnetic free layer structure; a first magnetic reference layer formed adjacent to the insulating tunnel junction layer opposite the magnetic free layer structure; a second magnetic reference layer separated from the first magnetic reference layer by a third perpendicular enhancement layer; an anti-ferromagnetic coupling layer formed adjacent to the second magnetic reference layer; and a magnetic fixed layer formed adjacent to the anti-ferromagnetic coupling layer. The first and second magnetic reference layers have a first invariable magnetization direction substantially perpendicular to layer planes thereof. The magnetic fixed layer has a second invariable magnetization direction substantially opposite to the first invariable magnetization direction.

First claim

What is claimed is:

1. A magnetic memory element comprising:
a magnetic free layer structure including:
first, second, and third magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof, said first, second, and third magnetic free layers each comprising cobalt and iron;
a first perpendicular enhancement layer (PEL) interposed between said first and second magnetic free layers and comprising one of magnesium, molybdenum, titanium, zirconium, vanadium, or aluminum; and
a second PEL interposed between said second and third magnetic free layers;

an insulating tunnel junction layer formed adjacent to said first magnetic free layer opposite said first PEL;
a magnetic reference layer structure including:
first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof, said first magnetic reference layer formed adjacent to said insulating tunnel junction layer opposite said first magnetic free layer; and
a third PEL interposed between said first and second magnetic reference layers;

an anti-ferromagnetic coupling layer formed adjacent to said second magnetic reference layer opposite said third PEL; and
a magnetic fixed layer formed adjacent to said anti-ferromagnetic coupling layer opposite said second magnetic reference layer, said magnetic fixed layer having a second invariable magnetization direction substantially opposite to said first invariable magnetization direction.

2. The magnetic memory element according to claim 1 , wherein said magnetic free layer structure is deposited on top of said insulating tunnel junction layer.

3. The magnetic memory element according to claim 1 , wherein said first, second, and third magnetic free layers have a body-centered cubic lattice structure.

4. The magnetic memory element according to claim 1 , wherein said first, second, and third magnetic free layers each further comprise boron.

5. The magnetic memory element according to claim 1 , wherein said second PEL comprises one of titanium, zirconium, vanadium, aluminum, magnesium, or molybdenum.

6. A magnetic memory element comprising:
a magnetic free layer structure including:
first, second, and third magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof, said first, second, and third magnetic free layers each comprising cobalt and iron;
a first perpendicular enhancement layer (PEL) interposed between said first and second magnetic free layers; and
a second PEL interposed between said second and third magnetic free layers and comprising one of magnesium, molybdenum, titanium, zirconium, vanadium, or aluminum;

an insulating tunnel junction layer formed adjacent to said first magnetic free layer opposite said first PEL;
a magnetic reference layer structure including:
first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof, said first magnetic reference layer formed adjacent to said insulating tunnel junction layer opposite said first magnetic free layer; and
a third PEL interposed between said first and second magnetic reference layers;

an anti-ferromagnetic coupling layer formed adjacent to said second magnetic reference layer opposite said third PEL; and
a magnetic fixed layer formed adjacent to said anti-ferromagnetic coupling layer opposite said second magnetic reference layer, said magnetic fixed layer having a second invariable magnetization direction substantially opposite to said first invariable magnetization direction.

7. The magnetic memory element according to claim 6 , wherein said magnetic free layer structure is deposited on top of said insulating tunnel junction layer.

8. The magnetic memory element according to claim 6 , wherein said first, second, and third magnetic free layers have a body-centered cubic lattice structure.

9. The magnetic memory element according to claim 6 , wherein said first, second, and third magnetic free layers each further comprise boron.

10. The magnetic memory element according to claim 6 , wherein said first PEL comprises one of titanium, zirconium, vanadium, aluminum, magnesium, or molybdenum.

11. A magnetic memory element comprising:
a magnetic free layer structure including:
first, second, and third magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof, said first, second, and third magnetic free layers each comprising cobalt and iron;
a first perpendicular enhancement layer (PEL) interposed between said first and second magnetic free layers and comprising one of beryllium or barium; and
a second PEL interposed between said second and third magnetic free layers;

an insulating tunnel junction layer formed adjacent to said first magnetic free layer opposite said first PEL;
a magnetic reference layer structure including:
first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof, said first magnetic reference layer formed adjacent to said insulating tunnel junction layer opposite said first magnetic free layer; and
a third PEL interposed between said first and second magnetic reference layers;

an anti-ferromagnetic coupling layer formed adjacent to said second magnetic reference layer opposite said third PEL; and
a magnetic fixed layer formed adjacent to said anti-ferromagnetic coupling layer opposite said second magnetic reference layer, said magnetic fixed layer having a second invariable magnetization direction substantially opposite to said first invariable magnetization direction.

12. The magnetic memory element according to claim 11 , wherein said magnetic free layer structure is deposited on top of said insulating tunnel junction layer.

13. The magnetic memory element according to claim 11 , wherein said first, second, and third magnetic free layers have a body-centered cubic lattice structure.

14. The magnetic memory element according to claim 11 , wherein said first, second, and third magnetic free layers each further comprise boron.

15. The magnetic memory element according to claim 11 , wherein said second PEL comprises one of magnesium, molybdenum, titanium, zirconium, vanadium, aluminum, beryllium, or barium.

16. A magnetic memory element comprising:
a magnetic free layer structure including:
first, second, and third magnetic free layers having a variable magnetization direction substantially perpendicular to layer planes thereof, said first, second, and third magnetic free layers each comprising cobalt and iron;
a first perpendicular enhancement layer (PEL) interposed between said first and second magnetic free layers; and
a second PEL interposed between said second and third magnetic free layers and comprising one of beryllium or barium;

an insulating tunnel junction layer formed adjacent to said first magnetic free layer opposite said first PEL;
a magnetic reference layer structure including:
first and second magnetic reference layers having a first invariable magnetization direction substantially perpendicular to layer planes thereof, said first magnetic reference layer formed adjacent to said insulating tunnel junction layer opposite said first magnetic free layer; and
a third PEL interposed between said first and second magnetic reference layers;

an anti-ferromagnetic coupling layer formed adjacent to said second magnetic reference layer opposite said third PEL; and
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Assignees

• Avalanche Technology Inc

Inventors

• Huai Yiming
• Wang Zihui

Classifications

• H10D48/385

  Devices using spin-polarised carriers · CPC title

• H01F10/3286

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

• H01F10/3254

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

• B82Y25/00

  Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance · CPC title