Spin current magnetization rotational element, spin-orbit-torque magnetoresistance effect element, magnetic memory, and high-frequency magnetic element

Patent metadata

Field	Value
Publication number	US-10665375-B2
Application number	US-201816116547-A
Country	US
Kind code	B2
Filing date	Aug 29, 2018
Priority date	Sep 1, 2017
Publication date	May 26, 2020
Grant date	May 26, 2020

Abstract

The present disclosure is directed to a spin current magnetization rotational element, a spin-orbit-torque magnetoresistance effect element, a magnetic memory, and a high-frequency magnetic element which can efficiently generate a pure spin current and reduce a reversal current density. The spin current magnetization rotational element includes: a spin-orbit torque wiring extending in a first direction; and a first ferromagnetic layer laminated in a second direction which intersects the first direction, wherein the spin-orbit torque wiring includes at least one rare gas element of Ar, Kr, and Xe.

First claim

What is claimed is:

1. A spin current magnetization rotational element, comprising:
a spin-orbit torque wiring extending in a first direction, a current flowing in the first direction; and
a first ferromagnetic layer laminated in a second direction which intersects the first direction,
wherein the spin-orbit torque wiring includes at least one rare gas element of Ar, Kr, and Xe.

2. The spin current magnetization rotational element according to claim 1 , wherein a molar ratio of the rare gas element is 0.005% or more and 2.00% or less of a total molar ratio of elements constituting the spin-orbit torque wiring.

3. The spin current magnetization rotational element according to claim 1 , wherein
the spin-orbit torque wiring is constituted of a plurality of layers laminated in the second direction, and
a concentration of the rare gas element is the highest at any one face among interfaces and surfaces of the plurality of layers.

4. The spin current magnetization rotational element according to claim 2 , wherein
the spin-orbit torque wiring is constituted of a plurality of layers laminated in the second direction, and
a concentration of the rare gas element is the highest at any one face among interfaces and surfaces of the plurality of layers.

5. The spin current magnetization rotational element according to claim 1 , wherein
the spin-orbit torque wiring is constituted of the plurality of layers laminated in the second direction,
the concentration of the rare gas element at a first interface closest to the first ferromagnetic layer among the interfaces of the plurality of layers is higher than the concentration of the rare gas element in a portion closer to the first ferromagnetic layer than the first interface in the spin-orbit torque wiring, and
a distance between the first interface and the first ferromagnetic layer in the second direction is shorter than a spin diffusion length of a material formed between the first ferromagnetic layer and the first interface.

6. The spin current magnetization rotational element according to claim 2 , wherein
the spin-orbit torque wiring is constituted of the plurality of layers laminated in the second direction,
the concentration of the rare gas element at a first interface closest to the first ferromagnetic layer among the interfaces of the plurality of layers is higher than the concentration of the rare gas element in a portion closer to the first ferromagnetic layer than the first interface in the spin-orbit torque wiring, and
a distance between the first interface and the first ferromagnetic layer in the second direction is shorter than a spin diffusion length of a material formed between the first ferromagnetic layer and the first interface.

7. The spin current magnetization rotational element according to claim 3 , wherein
the spin-orbit torque wiring is constituted of the plurality of layers laminated in the second direction,
the concentration of the rare gas element at a first interface closest to the first ferromagnetic layer among the interfaces of the plurality of layers is higher than the concentration of the rare gas element in a portion closer to the first ferromagnetic layer than the first interface in the spin-orbit torque wiring, and
a distance between the first interface and the first ferromagnetic layer in the second direction is shorter than a spin diffusion length of a material formed between the first ferromagnetic layer and the first interface.

8. The spin current magnetization rotational element according to claim 4 , wherein
the spin-orbit torque wiring is constituted of the plurality of layers laminated in the second direction,
the concentration of the rare gas element at a first interface closest to the first ferromagnetic layer among the interfaces of the plurality of layers is higher than the concentration of the rare gas element in a portion closer to the first ferromagnetic layer than the first interface in the spin-orbit torque wiring, and
a distance between the first interface and the first ferromagnetic layer in the second direction is shorter than a spin diffusion length of a material formed between the first ferromagnetic layer and the first interface.

9. The spin current magnetization rotational element according to claim 1 , wherein
the spin-orbit torque wiring is constituted of a plurality of layers laminated in the second direction, and
a first additional layer constituting the spin-orbit torque wiring is provided between a high-concentration layer in which a concentration of the rare gas element is the highest among the plurality of layers and the first ferromagnetic layer.

10. The spin current magnetization rotational element according to claim 9 , wherein a distance between the first ferromagnetic layer and the high-concentration layer in the second direction is shorter than a spin diffusion length of a material formed between the first ferromagnetic layer and the high-concentration layer.

11. The spin current magnetization rotational element according to claim 9 , wherein a second additional layer constituting the spin-orbit torque wiring is provided on a side of the high-concentration layer opposite to the first ferromagnetic layer.

12. The spin current magnetization rotational element according to claim 1 , wherein
the spin-orbit torque wiring is constituted of a plurality of layers laminated in the second direction, and
a high-concentration layer in which a concentration of the rare gas element is the highest among the plurality of layers is located closest to the first ferromagnetic layer.

13. The spin current magnetization rotational element according to claim 1 , wherein
the spin-orbit torque wiring is constituted of a plurality of layers laminated in the second direction, and
spin resistance of a first layer located on the first ferromagnetic layer side in two arbitrary layers among the plurality of layers is smaller than spin resistance of a second layer located away from the first ferromagnetic layer.

14. A spin-orbit-torque magnetoresistance effect element, comprising:
the spin current magnetization rotational element according to claim 1 ;
a nonmagnetic layer which is laminated on a surface on a side opposite to a surface in contact with the spin-orbit torque wiring in the first ferromagnetic layer; and
a second ferromagnetic layer, the nonmagnetic layer being sandwiched between the second ferromagnetic layer and the first ferromagnetic layer.

15. A magnetic memory, comprising:
a plurality of spin-orbit-torque magnetoresistance effect elements according to claim 14 .

16. A high-frequency magnetic element, comprising:
the spin-orbit-torque magnetoresistance effect element according to claim 14 .

Assignees

• Tdk Corp

Inventors

• Ota Minoru
• Sasaki Tomoyuki
• Takahashi Hirokazu

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

• 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

• G11C11/1675

  Writing or programming circuits or methods · CPC title

• H01F10/3254

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