Magnetic memory element and memory apparatus having multiple magnetization directions

Patent metadata

Field	Value
Publication number	US-9331270-B2
Application number	US-201414330748-A
Country	US
Kind code	B2
Filing date	Jul 14, 2014
Priority date	Nov 30, 2011
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

A memory element includes a layered structure: a memory layer having a magnetization direction changed depending on information, the magnetization direction being changed by applying a current in a lamination direction of the layered structure to record the information in the memory layer, including a first ferromagnetic layer having a magnetization direction that is inclined from a direction perpendicular to a film face, a bonding layer laminated on the first ferromagnetic layer, and a second ferromagnetic layer laminated on the bonding layer and bonded to the first ferromagnetic layer via the bonding layer, having a magnetization direction that is inclined from the direction perpendicular to the film face, a magnetization-fixed layer having a fixed magnetization direction, an intermediate layer that is provided between the memory layer and the magnetization-fixed layer, and is contacted with the first ferromagnetic layer, and a cap layer that is contacted with the second ferromagnetic layer.

First claim

What is claimed is:

1. A memory element, comprising a layered structure including:
a memory layer having a magnetization direction configured to be changed by in response to a current applied in a lamination direction of the layered structure to record information in the memory layer and at least including:
a first ferromagnetic layer,
a bonding layer laminated on the first ferromagnetic layer, and
a second ferromagnetic layer laminated on the bonding layer;

a fixed-magnetization layer having a fixed magnetization direction parallel to the lamination direction, the lamination direction being a direction perpendicular to a film face of the fixed-magnetization layer; and
an intermediate layer provided between the memory layer and the fixed-magnetization layer,
wherein a magnetization direction in an equilibrium state of the first ferromagnetic layer and a magnetization direction in an equilibrium state of the second ferromagnetic layer are respectively at a first and second predetermined angle relative to the fixed magnetization direction, wherein the first and second predetermined angles are more than 0 degrees and less than 180 degrees relative to the fixed magnetization direction, and the first predetermined angle is different in magnitude from the second predetermined angle.

2. The memory element according to claim 1 , wherein
the magnetization direction of the first ferromagnetic layer is closer to a direction parallel to the lamination direction than to a direction perpendicular to the lamination direction, and
the magnetization direction of the second ferromagnetic layer is closer to a direction perpendicular to the lamination direction than to a direction parallel to the lamination direction.

3. The memory element according to claim 2 , wherein
the angle formed by the magnetization direction of the first ferromagnetic layer and the direction perpendicular to the lamination direction is greater than the angle formed by the magnetization direction of the second ferromagnetic layer and the direction perpendicular to the lamination direction.

4. The memory element according to claim 1 , wherein
the magnetization direction of the first ferromagnetic layer is closer to a direction perpendicular to the lamination direction than to a direction parallel to the lamination direction, and
the magnetization direction of the second ferromagnetic layer is closer to a direction parallel to the lamination direction than to a direction perpendicular to the lamination direction.

5. The memory element according to claim 4 , wherein
the angle formed by the magnetization direction of the first ferromagnetic layer and the direction perpendicular to the lamination direction is smaller than the angle formed by the magnetization direction of the second ferromagnetic layer and the direction perpendicular to the lamination direction.

6. The memory element according to claim 1 , wherein the intermediate layer is a tunnel insulating layer.

7. The memory element according to claim 1 , further comprising a cap layer including an oxide layer.

8. The memory element according to claim 1 , wherein the first ferromagnetic layer and the second ferromagnetic layer respectively include a Co—Fe—B layer.

9. A memory apparatus, comprising:
a memory element having a layered structure including:
a memory layer having a magnetization direction configured to be changed by in response to a current applied in a lamination direction of the layered structure to record information in the memory layer and at least including:
a first ferromagnetic layer,
a bonding layer laminated on the first ferromagnetic layer, and
a second ferromagnetic layer laminated on the bonding layer;

a fixed-magnetization layer having a fixed magnetization direction parallel to the lamination direction, the lamination direction being a direction perpendicular to a film face of the fixed-magnetization layer; and
an intermediate layer provided between the memory layer and the fixed-magnetization layer,

wherein a magnetization direction in an equilibrium state of the first ferromagnetic layer and a magnetization direction in an equilibrium state of the second ferromagnetic layer are respectively at a first and second predetermined angle relative to the fixed magnetization direction, wherein the first and second predetermined angles are more than 0 degrees and less than 180 degrees relative to the fixed magnetization direction, and the first predetermined angle is different in magnitude from the second predetermined angle.

10. The memory apparatus according to claim 9 , wherein
the magnetization direction of the first ferromagnetic layer is closer to a direction parallel to the lamination direction than to a direction perpendicular to the lamination direction, and
the magnetization direction of the second ferromagnetic layer is closer to a direction perpendicular to the lamination direction than to a direction parallel to the lamination direction.

11. The memory apparatus according to claim 10 , wherein
the angle formed by the magnetization direction of the first ferromagnetic layer and the direction perpendicular to the lamination direction is greater than the angle formed by the magnetization direction of the second ferromagnetic layer and the direction perpendicular to the lamination direction.

12. The memory apparatus according to claim 9 , wherein
the magnetization direction of the first ferromagnetic layer is closer to a direction perpendicular to the lamination direction than to a direction parallel to the lamination direction, and
the magnetization direction of the second ferromagnetic layer is closer to a direction parallel to the lamination direction than to a direction perpendicular to the lamination direction.

13. The memory apparatus according to claim 12 , wherein
the angle formed by the magnetization direction of the first ferromagnetic layer and the direction perpendicular to the lamination direction is smaller than the angle formed by the magnetization direction of the second ferromagnetic layer and the direction perpendicular to the lamination direction.

14. The memory apparatus according to claim 9 , wherein the intermediate layer is a tunnel insulating layer.

15. The memory apparatus according to claim 9 , further comprising a cap layer including an oxide layer.

16. The memory apparatus according to claim 9 , wherein the first ferromagnetic layer and the second ferromagnetic layer respectively include a Co—Fe—B layer.

17. The memory element according to claim 1 , wherein the magnetization direction of the first ferromagnetic layer is closer to the fixed magnetization direction than to a direction perpendicular to the fixed magnetization direction.

18. The memory apparatus according to claim 9 , wherein the magnetization direction of the first ferromagnetic layer is closer to the fixed magnetization direction than to a direction perpendicular to the fixed magnetization direction.

19. The memory element according to claim 1 , wherein the equilibrium state is a state where no current is applied.

20. The memory apparatus according to claim 9 , wherein the equilibrium state is a state where no current is applied.

Assignees

• Sony Corp

Inventors

• Higo Yutaka
• Hosomi Masanori
• Ohmori Hiroyuki
• Bessho Kazuhiro
• Asayama Tetsuya
• Yamane Kazutaka
• Uchida Hiroyuki

Classifications

• H10D48/40

  Devices controlled by magnetic fields · CPC title

• H01L43/10 Primary

  Electricity · mapped topic

• G11C11/161

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

• H01L43/08

  Electricity · mapped topic

• H01L27/228

  Electricity · mapped topic