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

Patent metadata

Field	Value
Publication number	US-10921392-B2
Application number	US-201816138031-A
Country	US
Kind code	B2
Filing date	Sep 21, 2018
Priority date	Sep 26, 2017
Publication date	Feb 16, 2021
Grant date	Feb 16, 2021

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 stacked structure which is positioned on a nonmagnetic metal layer, the structure comprising:
a ferromagnetic layer; and
an intermediate layer interposed between the nonmagnetic metal layer and the ferromagnetic layer,
wherein the intermediate layer includes a NiAlX alloy layer represented by Formula (1),
Ni γ1 Al γ2 X γ3   (1);

wherein 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); and
wherein a value of γ3 changes along an in-plane direction or a thickness direction.

2. The stacked structure according to claim 1 ,
wherein the ferromagnetic layer includes a Heusler alloy represented by Formula (2):
Co 2 L α M β   (2); and

wherein, 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 stacked structure 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).

4. The stacked structure 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.

5. The stacked structure according to claim 1 ,
wherein the X in the NiAlX alloy layer is one or more elements selected from the group consisting of Si, Cr, Fe, Co, and Zr.

6. The stacked structure according to claim 1 ,
wherein, in Formula (1), an expression of 0<γ<0.3 is satisfied.

7. The stacked structure according to claim 1 ,
wherein, when a thickness of the NiAlX alloy layer is set as t1, an expression of 0.2 nm≤t1≤10 nm is satisfied.

8. A magnetoresistive effect element comprising:
the stacked structure according to claim 1 .

9. A magnetic head comprising:
the magnetoresistive effect element according to claim 8 .

10. A sensor comprising:
the magnetoresistive effect element according to claim 8 .

11. A high frequency filter comprising:
the magnetoresistive effect element according to claim 8 .

12. An oscillator comprising:
the magnetoresistive effect element according to claim 8 .

13. A stacked structure which is positioned on a nonmagnetic metal layer, the structure comprising:
a ferromagnetic layer; and
an intermediate layer interposed between the nonmagnetic metal layer and the ferromagnetic layer,
wherein the intermediate layer includes NiAlX alloy layer representated by Formula (1):
Ni γ1 Al γ2 X γ3   (1);

wherein 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); and
wherein a value of γ3 decreases as becoming farther from the ferromagnetic layer in a thickness direction thereof.

14. The stacked structure according to claim 13 ,
wherein the ferromagnetic layer includes Heusler alloy represented by Formula (2):
Co 2 L α M β   (2); and

wherein, 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 stacked structure 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).

16. The stacked structure 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.

17. The stacked structure according to claim 13 ,
wherein the X in the NiAlX alloy layer is one or more elements selected from the group consisting of Si, Cr, Fe, Co, and Zr.

18. The stacked structure according to claim 13 ,
wherein, in Formula (1), an expression of 0<γ<0.3 is satisfied.

19. The stacked structure according to claim 13 ,
wherein, when a thickness of the NiAlX alloy layer is set as t1, an expression of 0.2 nm≤t1≤10 nm is satisfied.

20. A magnetoresistive effect element comprising:
the stacked structure according to claim 13 .

21. A magnetic head comprising:
the magnetoresistive effect element according to claim 20 .

22. A sensor comprising:
the magnetoresistive effect element according to claim 20 .

23. A high frequency filter comprising:
the magnetoresistive effect element according to claim 20 .

24. An oscillator comprising:
the magnetoresistive effect element according to claim 20 .

Assignees

• Tdk Corp

Inventors

• INUBUSHI Kazuumi
• Nakada Katsuyuki

Classifications

• H01F10/3286

  Spin-exchange coupled multilayers having at least one layer with perpendicular magnetic anisotropy · CPC title

• G01R33/093 Primary

  using multilayer structures, e.g. giant magnetoresistance sensors (thin magnetic films H01F10/00) · CPC title

• G11B5/3929

  Disposition of magnetic thin films not used for directly coupling magnetic flux from the track to the MR film or for shielding · CPC title

• Y10T428/115

  Magnetic layer composition · CPC title

• G11B2005/3996

  large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices · CPC title