Stacked structure, magnetoresistive effect element, magnetic head, sensor, high frequency filter, and oscillator

Patent metadata

Field	Value
Publication number	US-11422211-B2
Application number	US-202117148686-A
Country	US
Kind code	B2
Filing date	Jan 14, 2021
Priority date	Sep 26, 2017
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A stacked structure is positioned on a nonmagnetic metal layer. The stacked structure includes a ferromagnetic layer and an intermediate layer interposed between the nonmagnetic metal layer and the ferromagnetic layer. The intermediate layer includes a NiAlX alloy layer represented by Formula (1): Niγ1Alγ2Xγ3 . . . (1), [X indicates one or more elements selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and satisfies an expression of 0<γ<0.5 in a case of γ=γ3/(γ1+γ2+γ3)].

First claim

What is claimed is:

1. A magnetoresistive effect element comprising:
a first ferromagnetic layer;
a second ferromagnetic layer; and
a nonmagnetic spacer layer that is disposed between the first ferromagnetic layer and the second ferromagnetic layer,
wherein the nonmagnetic spacer layer includes:
a nonmagnetic metal layer, and
at least one of a first intermediate layer provided under the nonmagnetic metal layer and a second intermediate layer provided over the nonmagnetic metal layer, the at least one of the first intermediate layer and the second intermediate layer being in contact with the nonmagnetic metal layer, and

the first intermediate layer and the second intermediate layer include an NiAlX alloy that is expressed by General Formula (1):
Ni γ1 Al γ2 X γ3   (1)

where
X indicates one element selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and 0<γ<0.5 in a case of γ=γ3/(γ1+γ2+γ3).

2. The magnetoresistive effect element according to claim 1 , wherein the ferromagnetic layer includes a Heusler alloy represented by Formula (2):
Co 2 L α M β   (2)

where when L indicates one or more elements selected from the group consisting of Mn and Fe, M indicates one or more elements selected from the group consisting of Si, Al, Ga, and Ge, and α and β are set to have positive values.

3. The magnetoresistive effect element according to claim 2 , wherein, in the Heusler alloy represented by Formula (2), α and β satisfy the following relational expressions (2-1) and (2-2):
0.7<α<1.6  (2-1)

2<α+β<2.6  (2-3).

4. The magnetoresistive effect element according to claim 2 , wherein, in the Heusler alloy represented by Formula (2), α and β satisfy the following relational expressions (2-1), (2-2), and (2-3):
0.7<α<1.6  (2-1)

0.65<β<1.35  (2-2)

2<α+β<2.6  (2-3).

5. The magnetoresistive effect element according to claim 1 , wherein the nonmagnetic metal layer includes one or more elements selected from the group consisting of Ag, Cr, Al, Au, and NiAl.

6. The magnetoresistive effect element according to claim 1 , wherein X in the NiAlX alloy is one or more elements selected from the group consisting of Si, Cr, Fe, Co, and Zr.

7. The magnetoresistive effect element according to claim 1 , wherein, in Formula (1), an expression of 0<γ<0.3 is satisfied.

8. The magnetoresistive effect element according to claim 1 , wherein, when a thickness of the NiAlX alloy is set as t 1 , an expression of 0.2 nm≤t 1 ≤10 nm is satisfied.

9. A magnetic head comprising the magnetoresistive effect element according to claim 1 .

10. A sensor comprising the magnetoresistive effect element according to claim 1 .

11. A high frequency filter comprising the magnetoresistive effect element according to claim 1 .

12. An oscillator comprising the magnetoresistive effect element according to claim 1 .

13. A magnetoresistive effect element comprising:
a first ferromagnetic layer;
a second ferromagnetic layer; and
a nonmagnetic spacer layer that is disposed between the first ferromagnetic layer and the second ferromagnetic layer,
wherein the nonmagnetic spacer layer includes:
a nonmagnetic metal layer, and
at least one of a first intermediate layer provided under the nonmagnetic metal layer and a second intermediate layer provided over the nonmagnetic metal layer,

the first intermediate layer and the second intermediate layer include an NiAlX alloy that is expressed by General Formula (1):
Ni γ1 Al γ2 X γ3   (1)

where X indicates one element selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and 0<γ<0.5 in a case of γ=γ3/(γ1+γ2+γ3), and
a value of γ 3 changes along an in-plane direction or a thickness direction thereof.

14. The magnetoresistive effect element according to claim 13 , wherein the ferromagnetic layer includes a Heusler alloy represented by Formula (2):
Co 2 L α M β   (2)

where when L indicates one or more elements selected from the group consisting of Mn and Fe, M indicates one or more elements selected from the group consisting of Si, Al, Ga, and Ge, and α and β are set to have positive values.

15. The magnetoresistive effect element according to claim 14 , wherein, in the Heusler alloy represented by Formula (2), α and β satisfy the following relational expressions (2-1) and (2-2):
0.7<α<1.6  (2-1)

2<α+β<2.6  (2-3).

16. The magnetoresistive effect element according to claim 14 , wherein, in the Heusler alloy represented by Formula (2), α and β satisfy the following relational expressions (2-1), (2-2), and (2-3):
0.7<α<1.6  (2-1)

0.65<β<1.35  (2-2)

2<α+β<2.6  (2-3).

17. The magnetoresistive effect element according to claim 13 , wherein the nonmagnetic metal layer includes one or more elements selected from the group consisting of Ag, Cr, Al, Au, and NiAl.

18. The magnetoresistive effect element according to claim 13 , wherein X in the NiAlX alloy is one or more elements selected from the group consisting of Si, Cr, Fe, Co, and Zr.

19. The magnetoresistive effect element according to claim 13 , wherein, in Formula (1), an expression of 0<γ<0.3 is satisfied.

20. The magnetoresistive effect element according to claim 13 , wherein, when a thickness of the NiAlX alloy is set as t 1 , an expression of 0.2 nm≤t 1 ≤10 nm is satisfied.

21. A magnetic head comprising the magnetoresistive effect element according to claim 13 .

22. A sensor comprising the magnetoresistive effect element according to claim 13 .

23. A high frequency filter comprising the magnetoresistive effect element according to claim 13 .

24. An oscillator comprising the magnetoresistive effect element according to claim 13 .

25. A magnetoresistive effect element comprising:
a first ferromagnetic layer;
a second ferromagnetic layer; and
a nonmagnetic spacer layer that is disposed between the first ferromagnetic layer and the second ferromagnetic layer,
wherein the nonmagnetic spacer layer includes:
a nonmagnetic metal layer, and
at least one of a first intermediate layer provided under the nonmagnetic metal layer and a second intermediate layer provided over the nonmagnetic metal layer,

the first intermediate layer and the second intermediate layer include an NiAlX alloy that is expressed by General Formula (1):
Ni γ1 Al γ2 X γ3   (1)

where X indicates one element selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and 0<γ<0.5 in a case of γ=γ3/(γ1+γ2+γ3), and
a value of γ 3 decreases as becoming farther from the ferromagnetic layer in a thickness direction thereof.

26. The magnetoresistive effect element according to claim 25 , wherein the ferromagnetic layer includes a Heusler alloy represented by Formula (2):
Co 2 L α M β   (2)

where when L indicates one or more elements selected from the group consisting of Mn and Fe, M indicates one or more elements selected from the group consisting of Si, Al, Ga, and Ge, and α and β are set to have positive values.

27. The magnetoresistive effect element according to claim 26 , wherein, in the Heusler alloy represented by Formula (2), α and β satisfy the following relational expressions (2-1) and (2-2):
0.7<α<1.6  (2-1)

2<α+β<2.6  (2-3).

28. The magnetoresistive effect element according to claim 26 , wherein, in the Heusler alloy represented by Formula (2)

Assignees

• Tdk Corp

Inventors

• INUBUSHI Kazuumi
• Nakada Katsuyuki

Classifications

• G11C11/16

  using elements in which the storage effect is based on magnetic spin effect · CPC title

• Y10T428/115

  Magnetic layer composition · CPC title

• H01F10/30

  characterised by the composition of the intermediate layers {, e.g. seed, buffer, template, diffusion preventing, cap layers (H01F10/06 and H01F10/32 take precedence)} · CPC title

• G11C11/161

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

• G01R33/1284

  Spin resolved measurements; Influencing spins during measurements, e.g. in spintronics devices · CPC title