Spin-orbit-torque magnetization rotational element and magnetic memory

Patent metadata

Field	Value
Publication number	US-11264563-B2
Application number	US-201816629895-A
Country	US
Kind code	B2
Filing date	Aug 31, 2018
Priority date	Sep 4, 2017
Publication date	Mar 1, 2022
Grant date	Mar 1, 2022

Abstract

A spin-orbit-torque magnetization rotational element includes: a ferromagnetic metal layer, a magnetization direction of the ferromagnetic metal layer being configured to change; a spin-orbit torque wiring which extends in the first direction intersecting a lamination direction of the ferromagnetic metal layer and is joined to the ferromagnetic metal layer; and two via wires, each of which extends in a direction intersecting the spin-orbit torque wiring from a surface of the spin-orbit torque wiring opposite to a side with the ferromagnetic metal layer and is connected to a semiconductor circuit, wherein a via-to-via distance between the two via wires in the first direction is shorter than a width of the ferromagnetic metal layer in the first direction.

First claim

The invention claimed is:

1. A spin-orbit-torque magnetization rotational element, comprising:
a ferromagnetic metal layer, a magnetization direction of the ferromagnetic metal layer being configured to change;
a spin-orbit torque wiring which extends in a first direction intersecting a lamination direction of the ferromagnetic metal layer and is joined to the ferromagnetic metal layer; and
two via wires, each of the two via wires (1) extends in a direction intersecting the first direction, (2) is located at a first surface of the spin-orbit torque wiring which is opposite to a second surface of the spin-orbit torque wiring at which the ferromagnetic metal layer is located, and (3) is connected to a semiconductor circuit,
wherein
a via-to-via distance between the two via wires in the first direction is shorter than a width of the ferromagnetic metal layer in the first direction,
the spin-orbit torque wiring has a laminated structure in a lamination direction of the spin-orbit torque wiring, and
a resistance value of a first layer of the spin-orbit torque wiring on a ferromagnetic metal layer side is lower than a resistance value of a second layer of the spin-orbit torque wiring provided on a via wires side.

2. A spin-orbit-torque magnetization rotational element, comprising:
a ferromagnetic metal layer, a magnetization direction of the ferromagnetic metal layer being configured to change;
a spin-orbit torque wiring which extends in a first direction intersecting a lamination direction of the ferromagnetic metal layer and is joined to the ferromagnetic metal layer;
two via wires, each of the two via wires (1) extends in a direction intersecting the first direction, (2) is located at a first surface of the spin-orbit torque wiring which is opposite to a second surface of the spin-orbit torque wiring at which the ferromagnetic metal layer is located, and (3) is connected to a semiconductor circuit; and
a planarizing layer between the via wires and the spin-orbit torque wiring,
wherein a via-to-via distance between the two via wires in the first direction is shorter than a width of the ferromagnetic metal layer in the first direction.

3. The spin-orbit-torque magnetization rotational element according to claim 2 , wherein the planarizing layer is made of a nitride containing Ti or Ta.

4. A spin-orbit-torque magnetization rotational element, comprising:
a ferromagnetic metal layer, a magnetization direction of the ferromagnetic metal layer being configured to change;
a spin-orbit torque wiring which extends in a first direction intersecting a lamination direction of the ferromagnetic metal layer and is joined to the ferromagnetic metal layer; and
two via wires, each of the two via wires (1) extends in a direction intersecting the first direction, (2) is located at a first surface of the spin-orbit torque wiring which is opposite to a second surface of the spin-orbit torque wiring at which the ferromagnetic metal layer is located, and (3) is connected to a semiconductor circuit, wherein
a via-to-via distance between the two via wires in the first direction is shorter than a width of the ferromagnetic metal layer in the first direction, and
in a lamination surface for the ferromagnetic metal layer to be laminated thereon, a Vickers hardness difference between the two via wires and an interlayer insulating part configured to insulate between the two via wires is 3 GPa or less.

5. The spin-orbit-torque magnetization rotational element according to claim 1 , wherein, in a lamination surface for the ferromagnetic metal layer to be laminated thereon, a Vickers hardness difference between the two via wires and an interlayer insulating part configured to insulate between the two via wires is 3 GPa or less.

6. The spin-orbit-torque magnetization rotational element according to claim 2 , wherein, in a lamination surface for the ferromagnetic metal layer to be laminated thereon, a Vickers hardness difference between the two via wires and an interlayer insulating part configured to insulate between the two via wires is 3 GPa or less.

7. The spin-orbit-torque magnetization rotational element according to claim 3 , wherein, in a lamination surface for the ferromagnetic metal layer to be laminated thereon, a Vickers hardness difference between the two via wires and an interlayer insulating part configured to insulate between the two via wires is 3 GPa or less.

8. The spin-orbit-torque magnetization rotational element according to claim 3 , further comprising:
a non-magnetic layer and a magnetization fixed layer, a magnetization direction of the magnetization fixed layer being configured to be fixed to the ferromagnetic metal layer provided on a surface of the ferromagnetic metal layer opposite to a side with the spin-orbit torque wiring.

9. The spin-orbit-torque magnetization rotational element according to claim 4 , further comprising:
a non-magnetic layer and a magnetization fixed layer, a magnetization direction of the magnetization fixed layer being configured to be fixed to the ferromagnetic metal layer provided on a surface of the ferromagnetic metal layer opposite to a side with the spin-orbit torque wiring.

10. A magnetic memory comprising:
a plurality of the spin-orbit-torque magnetization rotational elements according to claim 9 .

11. The spin-orbit-torque magnetization rotational element according to claim 1 , further comprising:
a planarizing layer between the via wires and the spin-orbit torque wiring.

12. The spin-orbit-torque magnetization rotational element according to claim 11 , wherein the planarizing layer is made of a nitride containing Ti or Ta.

13. The spin-orbit-torque magnetization rotational element according to claim 1 , further comprising:
a non-magnetic layer and a magnetization fixed layer, a magnetization direction of the magnetization fixed layer being configured to be fixed to the ferromagnetic metal layer provided on a surface of the ferromagnetic metal layer opposite to a side with the spin-orbit torque wiring.

14. The spin-orbit-torque magnetization rotational element according to claim 13 , wherein an area of the ferromagnetic metal layer when viewed in a plan view from a vertical direction is larger than an area of the magnetization fixed layer when viewed in a plan view from the vertical direction.

15. A magnetic memory comprising:
a plurality of the spin-orbit-torque magnetization rotational elements according to claim 13 .

16. The spin-orbit-torque magnetization rotational element according to claim 2 , further comprising:
a non-magnetic layer and a magnetization fixed layer, a magnetization direction of the magnetization fixed layer being configured to be fixed to the ferromagnetic metal layer provided on a surface of the ferromagnetic metal layer opposite to a side with the spin-orbit torque wiring.

17. A magnetic memory comprising:
a plurality of the spin-orbit-torque magnetization rotational elements according to claim 16 .

Assignees

• Tdk Corp

Inventors

• SUDA Keita
• Sasaki Tomoyuki

Classifications

• H10D48/40

  Devices controlled by magnetic fields · CPC title

• G11C11/161 Primary

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

• H01L43/08 Primary

  Electricity · mapped topic

• H01L43/02

  Electricity · mapped topic

• H01L27/222

  Electricity · mapped topic