Magnetoresistance effect element and method for producing the same, and magnetoresistance effect type head, magnetic recording apparatus, and magnetoresistance effect memory element

• US 6,567,246 B1
• Filed: 03/01/2000
• Issued: 05/20/2003
• Est. Priority Date: 03/02/1999
• Status: Expired due to Fees

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Sugita, Yasunari, Hiramoto, Masayoshi, Kawawake, Yasuhiro, Matsukawa, Nozomu, Sakakima, Hiroshi, Satomi, Mitsuo
• Primary Examiner(s): Ometz, David L.
• Assistant Examiner(s): CASTRO, ANGEL A
• Application Number:
  US09/516,552
• Time in Patent Office: 1,175 Days
• Field of Search: 360/324.11, 360/324.1, 360/324.12, 360/324, 360/313, 360/314, 324/252, 365/758
• US Class Current: 360/324.11
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: G11B 2005/3996 large or giant magnetoresistive effects [GMR], e.g. as generated in spin-valve [SV] devices
• CPC Class Codes: G11B 5/00 Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor G11B11/00 and G11B13/00 take precedence
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence
• CPC Class Codes: G11B 5/3903 using magnetic thin film layers or their effects, the films being part of integrated structures
• CPC Class Codes: G11B 5/3925 the two parts being thin films
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: G11C 11/1675 Writing or programming circuits or methods
• CPC Class Codes: H01F 10/3268 the exchange coupling being asymmetric, e.g. by use of additional pinning, by using antiferromagnetic or ferromagnetic coupling interface, i.e. so-called spin-valve [SV] structure, e.g. NiFe/Cu/NiFe/FeMn
• CPC Class Codes: H01F 41/18 by cathode sputtering
• CPC Class Codes: H01F 41/302 for applying spin-exchange-coupled multilayers, e.g. nanostructured superlattices spin-exchange-coupled multilayers H01F10/32
• CPC Class Codes: H10N 50/10 Magnetoresistive devices

Abstract

A magnetoresistance effect element includes a free layer, in which a magnetization direction thereof is easily rotated in response to an external magnetic field, a first non-magnetic layer, and a first pinned layer provided on a side opposite to the free layer of the first non-magnetic layer, in which a magnetization direction of the first pinned layer is not easily rotated in response to the external magnetic field. At least one of the first pinned layer and the free layer includes a first metal magnetic film contacting the first non-magnetic layer, and a first oxide magnetic film.

Claims

1. A magnetoresistance effect element comprising:

a free layer, wherein a magnetization direction thereof is easily rotated in response to an external magnetic field;

a first non-magnetic layer; and

a first pinned layer provided on a side opposite to the free layer of the first non-magnetic layer, wherein a magnetization direction of the first pinned layer is not easily rotated in response to the external magnetic field,

wherein at least one of the first pinned layer and the free layer includes a first metal magnetic film contacting the first non-magnetic layer, and a first oxide magnetic film, and

the first pinned layer includes the first metal magnetic film and the first oxide magnetic film.

2. A magnetoresistance effect element according to claim 1 further comprising:

a second non-magnetic layer provided on a side opposite to the first non-magnetic layer of the free layers and

a second pinned layer provided on a side opposite to the free layer of the second non-magnetic layer wherein a magnetization direction of the second pinned layer is not easily rotated in response to the external magnetic field.

3. A magnetoresistance effect element according to claim 1, wherein the free layer includes the first metal magnetic film and the first oxide magnetic film.

4. A magnetoresistance effect element according to claim 3, wherein the free layer further comprises a second metal magnetic film provided on a side opposite to the first metal magnetic film of the first oxide magnetic film.

5. A magnetoresistance effect element according to claim 1 further comprising:

an oxide non-magnetic film provided on a side opposite to the first non-magnetic layer of the free layer, having satisfactory flatness.

6. A magnetoresistance effect element according to claim 1 further comprising:

a pinning layer magnetically coupled to the first oxide magnetic film.

7. A magnetoresistance effect element according to claim 6, wherein the pinning layer comprises P˜

Mn where P is at least one element selected from Pt, Ni, Pd, Ir, Rh, Ru, and Cr.

8. A magnetoresistance effect element according to claim 6, wherein the pinning layer comprises either α

-Fe₂O₃ or NiO, or both, or includes an α

-Fe₂O₃ film and a NiO film.

9. A magnetoresistance effect element according to claim 6, wherein the pinning layer comprises an (AB)₂O_x layer where a ratio of a combination of element A and element B to oxygen is equal to 2:

x;

2.8<

x<

32; and

where t is defined as;

10. A magnetoresistance effect element according to claim 9, wherein element B of the (AB)_zO_x layer comprises at least one transition metal, and has Fe as a major component.

11. A magnetoresistance effect element according to claim 9, wherein element of the (AB)_zO_x layer comprises at least one element selected from rare earth metals.

12. A magnetoresistance effect element according to claim 1 further comprising:

a pinning layer magnetically coupled to the first pinned layer.

13. A magnetoresistance effect element according to claim 1, wherein the first pinned layer further comprises a second metal magnetic film provided on a side opposite to the first metal magnetic film of the first oxide magnetic film.

14. A magnetoresistance effect element according to claim 13, wherein the first pinned layer further comprises:

a third metal magnetic film; and

an exchange-coupling non-magnetic film antiferromagnetically exchange-coupling the second and third metal magnetic films.

15. A magnetoresistance effect element according to claim 13, wherein the free layer comprises a non-magnetic film and two metal magnetic films which are antiferromagnetically exchange-coupled via the non-magnetic film;

and the two films have different thicknesses or different levels of saturated magnetization.

16. A magnetoresistance effect element according to claim 1, wherein the first pinned layer further comprises:

a non-magnetic film provided on a side opposite to the first metal magnetic film of the first oxide magnetic film; and

a second oxide magnetic film magnetically exchange-coupling the first oxide magnetic film via the non-magnetic films.

17. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film comprises Fe.

18. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film comprises Fe and X, where X is at least one element selected from Al, Si, B and N.

19. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film comprises MFe₂O₄ as a major component where M is at least one element selected from Fe, Co, and Ni.

20. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film comprises Fe₃O₄ as a major component.

21. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film comprises CoFe₂O₄ as a major component.

22. A magnetoresistance effect element according to claim 1, wherein the first oxide magnetic film is an oxide of the first metal magnetic film.

23. A magnetoresistance effect element according to claim 22, the first metal magnetic film comprises a Co—

Fe alloy.

24. A magnetoresistance effect element according to claim 1, wherein the magnetoresistance effect element further comprises electrodes provided on the upper and lower sides thereof, and a current flows vertically through the magnetoresistance effect element.

25. A magnetoresistance effect type head comprising:

a magnetoresistance effect element according to claim 1; and

a shield.

26. A magnetic recording apparatus comprising:

a magnetoresistance affect type head according to claim 25;

a servo section for controlling the magnetoresistance effect type head to track a recording medium; and

a signal processing section for processing a signal which the magnetoresistance effect type head records or reproduces onto or from the recording medium.

27. A magnetoresistance effect type head comprising

a magnetoresistance effect element according to claim 1;

and

a yoke for introducing a magnetic field into the magnetoresistance effect element.

28. A magnetoresistance effect memory element comprising:

a magnetoresistance effect element according to claim 1;

an information reading lead line for reading information from the magnetoresistance effect element; and

an information recording lead line for recording the information into the magnetoresistance effect element.