Memory element and memory apparatus

• US 9,484,528 B2
• Filed: 04/11/2016
• Issued: 11/01/2016
• Est. Priority Date: 11/30/2011
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Higo, Yutaka, Hosomi, Masanori, Ohmori, Hiroyuki, Bessho, Kazuhiro, Asayama, Tetsuya, Yamane, Kazutaka, Uchida, Hiroyuki
• Primary Examiner(s): MILLER, JAMI VALENTINE
• Application Number:
  US15/095,553
• Publication Number:
  US 20160225980A1
• Time in Patent Office: 204 Days
• Field of Search: 257/20, 257/414, 257421-427, 257/E29.323, 438/3, 360324-326, 365157-158, 365171-173
• US Class Current: 1/1
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: H01L 29/82 controllable by variation of the magnetic field applied to the device
• CPC Class Codes: H10B 61/00 Magnetic memory devices, e.g. magnetoresistive RAM [MRAM] devices
• CPC Class Codes: H10B 61/22 of the field-effect transistor [FET] type
• CPC Class Codes: H10N 50/10 Magnetoresistive devices
• CPC Class Codes: H10N 50/85 Magnetic active materials

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.

Claims

1. A memory element, comprising a layered structure comprising:

a memory layer 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 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 not parallel or antiparallel to the fixed magnetization direction and are not parallel to one another.

2. The memory element according to claim 1, wherein

the first predetermined angle is closer to a direction perpendicular to the film face than to a direction parallel to the film face, and

the second predetermined angle is closer to the direction parallel to the film face than to the direction perpendicular to the film face.

3. The memory element according to claim 2, wherein the first predetermined angle is greater than the second predetermined angle.

4. The memory element according to claim 1, wherein

the first predetermined angle is closer to a direction parallel to the film face than to a direction perpendicular to the film face, and

the second predetermined angle is closer to the direction perpendicular to the film face than to the direction perpendicular to the film face.

5. The memory element according to claim 4, wherein the first predetermined angle is smaller than the second predetermined angle.

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. The memory element according to claim 1, wherein a magnetization of the memory layer is changeable by a current applied in the fixed magnetization direction.

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

11. A memory apparatus, comprising:

a memory element having a layered structure including;

a memory layer 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 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 not parallel or antiparallel to the fixed magnetization direction and are not parallel to one another.

12. The memory apparatus according to claim 11, wherein

the first predetermined angle is closer to a direction perpendicular to the film face than to a direction parallel to the film face, and

the second predetermined angle is closer to the direction parallel to the film face than to the direction perpendicular to the film face.

13. The memory apparatus according to claim 12, wherein the first predetermined angle is greater than the second predetermined angle.

14. The memory apparatus according to claim 11, wherein

the first predetermined angle is closer to a direction parallel to the film face than to a direction perpendicular to the film face, and

the second predetermined angle is closer to the direction perpendicular to the film face than to the direction perpendicular to the film face.

15. The memory apparatus according to claim 14, wherein the first predetermined angle is smaller than the second predetermined angle.

16. The memory apparatus according to claim 11, wherein the intermediate layer is a tunnel insulating layer.

17. The memory apparatus according to claim 11, further comprising a cap layer including an oxide layer.

18. The memory apparatus according to claim 11, wherein the first ferromagnetic layer and the second ferromagnetic layer respectively include a Co—

Fe—

B layer.

19. The memory apparatus according to claim 11, wherein a magnetization of the memory layer is changeable by a current applied in the fixed magnetization direction.

20. The memory apparatus according to claim 11, wherein the equilibrium state is a state where no current is applied.