Magnetic memory element and memory device

Patent metadata

Field	Value
Publication number	US-9818464-B2
Application number	US-201615263952-A
Country	US
Kind code	B2
Filing date	Sep 13, 2016
Priority date	Mar 13, 2014
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

According to one embodiment, a magnetic memory element includes a stacked structure. The stacked structure includes a first and a second stacked member. The first stacked member includes a first and second ferromagnetic layer. A magnetic resonance frequency of the second ferromagnetic layer is a first frequency. A direction of a magnetization of the second ferromagnetic layer is settable to a direction of a first current when a magnetic field of the first frequency is applied to the first stacked member and the first current flows in the first stacked member. The direction of the magnetization of the second ferromagnetic layer does not change when the second current smaller than the first current flows in the first stacked member. The second stacked member includes a third ferromagnetic layer. A magnetization of the third ferromagnetic layer can generate a magnetic field of the first frequency by the second current.

First claim

What is claimed is:

1. A memory device, comprising:
a magnetic memory element: and a controller electrically connected to the magnetic memory element, wherein the magnetic memory element comprises:
a stacked structure, comprising:
a first stacked member, comprising:
a first ferromagnetic layer,
a second ferromagnetic layer, and
a first nonmagnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer,
a magnetic resonance frequency of the second ferromagnetic layer being a first frequency, a direction of a magnetization of the second ferromagnetic layer being settable to a direction corresponding to an orientation of a first current when a magnetic field of the first frequency is applied to the first stacked member and the first current flows in the first stacked member along a first direction connecting the first ferromagnetic layer and the second ferromagnetic layer, the direction of the magnetization of the second ferromagnetic layer not changing to a direction corresponding to an orientation of a second current smaller than the first current when the second current flows in the first stacked member, and

a second stacked member stacked with the first stacked member along the first direction, the second stacked member including a third ferromagnetic layer, a magnetization of the third ferromagnetic layer being able to generate a magnetic field of the first frequency by the second current flowing in the second stacked member along the first direction,

the direction of the magnetization of the second ferromagnetic layer being settable to a direction corresponding to an orientation of a current by causing the current to flow in the first stacked member and the second stacked member along the first direction to generate a magnetic field acting on the second ferromagnetic layer,
the controller causing a larger current to flow in the second stacked member than in the first stacked member in a programming operation of programming data to the magnetic memory element, and
the controller causing a smaller current to flow in the second stacked member than in the first stacked member in a read-out operation of reading the data retained in the magnetic memory element.

2. The memory device according to claim 1 , wherein the third ferromagnetic layer comprises a Heusler alloy comprising at least one selected from the group consisting of Co, Mn, Fe, Ni, Cu, Rh, Ru, and Pd.

3. The memory device according to claim 1 , wherein the third ferromagnetic layer comprises at least one selected from the group consisting of Co 2 MnGa, Co 2 MnAl, Ni 2 MnIn, Ni 2 MnGa, Ni 2 MnSn, Pd 2 MnSb, Pd 2 MnSn, Cu 2 MnAl, Cu 2 MnSn, Cu 2 MnIn, Rh 2 MnGe, and Rh 2 MnPb.

4. The memory device according to claim 1 , wherein the third ferromagnetic layer comprises at least one selected from a group consisting of Co 2 FeSi, Co 2 FeAl, Co 2 FeGa, Co 2 MnGe, Co 2 MnSn, and Co 2 MnSi.

5. The memory device according to claim 1 , wherein a cross-sectional area of the first stacked member when cut by a plane perpendicular to the first direction is greater than a cross-sectional area of the second stacked member when cut by a plane perpendicular to the first direction.

6. The memory device according to claim 1 , wherein
the second ferromagnetic layer includes:
a first portion; and
a second portion stacked with the first portion in the first direction,

a magnetic resonance frequency of the second portion is lower than a magnetic resonance frequency of the first portion, and
directions of magnetizations of the first portion and the second portion can be set to a direction corresponding to the orientation of the current flowing in the second stacked member by the current flowing in the second stacked member.

7. The device according to claim 1 , wherein
the second stacked member further comprises:
a fourth ferromagnetic layer stacked with the third ferromagnetic layer in the first direction; and
a second nonmagnetic layer provided between the third ferromagnetic layer and the fourth ferromagnetic layer.

8. The memory device according to claim 7 , wherein an orientation of a first-direction component of the magnetization of the first ferromagnetic layer is reverse of an orientation of the first-direction component of a magnetization of the fourth ferromagnetic layer.

9. The memory device according to claim 1 , wherein
a perpendicular magnetization component parallel to the first direction of a magnetization of the first ferromagnetic layer is larger than an in-plane magnetization component perpendicular to the first direction of the magnetization of the first ferromagnetic layer,
the perpendicular magnetization component of the magnetization of the second ferromagnetic layer is larger than the in-plane magnetization component of the magnetization of the second ferromagnetic layer, and
the perpendicular magnetization component of the magnetization of the third ferromagnetic layer is smaller than the in-plane magnetization component of the magnetization of the third ferromagnetic layer.

10. The memory device according to claim 1 , wherein the stacked structure further comprises a magnetic shield facing at least a portion of a side surface of the stacked structure.

11. A memory device, comprising:
a magnetic memory element: and
a controller electrically connected to the magnetic memory element,
wherein the magnetic memory element comprises:
a stacked structure, comprising:
a first stacked member, comprising:
a first ferromagnetic layer,
a second ferromagnetic layer, and
a first nonmagnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer,
a magnetic resonance frequency of the second ferromagnetic layer being a first frequency, a direction of a magnetization of the second ferromagnetic layer being settable to a direction corresponding to an orientation of a first current when a magnetic field of the first frequency is applied to the first stacked member and the first current flows in the first stacked member along a first direction connecting the first ferromagnetic layer and the second ferromagnetic layer, the direction of the magnetization of the second ferromagnetic layer not changing to a direction corresponding to an orientation of a second current smaller than the first current when the second current flows in the first stacked member, and

a second stacked member stacked with the first stacked member along the first direction, the second stacked member including a third ferromagnetic layer, a magnetization of the third ferromagnetic layer being able to generate a magnetic field of the first frequency by the second current flowing in the second stacked member along the first direction,

the direction of the magnetization of the second ferromagnetic layer being settable to a direction corresponding to an orientation of a current by causing the current to flow in the first stacked member and the second stacked member along the first direction to generate a magnetic field acting on the second ferromagnetic layer,
the controller causing a current to flow in the second stacked member without causing a current to flow in the first stacked member in a programming operation of programming data to the magnetic memory element, and
the controller causing a current to flow in the first stacked member without causing a current to flow in the second stacked member in a read-out operation of reading the data retained in the magnetic memory element.

12. A memory device, comprising:
a magnetic memory element; and
a controller electrically connected to the magnetic memory element,
wherein the magnetic memory element comprises

Assignees

• Toshiba Kk

Inventors

• Saida Daisuke
• Amano Minoru
• Ozeki Jyunichi
• Shimomura Naoharu

Classifications

• H01F10/3277

  by use of artificial ferrimagnets [AFI] only · CPC title

• H01L43/10

  Electricity · mapped topic

• G11C11/1675

  Writing or programming circuits or methods · CPC title

• G11C11/161 Primary

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

• G11C11/1673

  Reading or sensing circuits or methods · CPC title