Magnetoresistance effect element, magnetic head and magnetic recording and/or reproducing system

• US 7,542,248 B2
• Filed: 11/23/2007
• Issued: 06/02/2009
• Est. Priority Date: 09/11/2000
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Yuasa, Hiromi, Yoda, Hiroaki, Nagata, Tomohiko, Kamiguchi, Yuuzo
• Primary Examiner(s): Miller; Brian E
• Application Number:
  US11/984,865
• Publication Number:
  US 20080088981A1
• Time in Patent Office: 557 Days
• Field of Search: 360/324.11, 360/324.12, 324/207.22, 324/207.21, 324/252, 338/32.R
• 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: G01R 33/093 using multilayer structures, e.g. giant magnetoresistance sensors thin magnetic films H01F10/00
• 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 5/3903 using magnetic thin film layers or their effects, the films being part of integrated structures
• CPC Class Codes: G11C 11/15 using multiple magnetic layers G11C11/155 takes precedence

Abstract

There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. In a magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, if a pinned layer and a free layer have a stacked construction of a magnetic layer and a non-magnetic layer or a stacked construction of a magnetic layer and a magnetic layer, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.

Claims

1. A magnetoresistance effect element comprising:

a magnetization fixed layer in which a direction of magnetization is substantially fixed to one direction, the magnetization fixed layer having a first stacked body including first and second ferromagnetic films, the first and second ferromagnetic films in the first stacked body being ferromagnetically coupled to each other in the first stacked body;

a magnetization free layer in which a direction of magnetization varies in response to an external magnetic field, the magnetization free layer having a second stacked body including third and fourth ferromagnetic films, the third and fourth ferromagnetic films in the second stacked body being ferromagnetically coupled to each other in the second stacked body;

a non-magnetic intermediate layer provided between the magnetization fixed layer and the magnetization free layer;

a high conductive layer provided on a surface of the magnetization free layer opposite from the non-magnetic intermediate layer, the high conductive layer having a higher conductivity than those of the magnetization fixed layer and the magnetization free layer;

a resistance of the magnetoresistance effect element varying in accordance with a relative angle between the direction of magnetization of the magnetization fixed layer and the direction of magnetization of the magnetization free layer; and

a sense current flowing to the magnetization fixed layer, the non-magnetic intermediate layer and the magnetization free layer in a direction substantially perpendicular to surfaces of those layers.

2. The magnetoresistance effect element as set forth in claim 1, further comprising an antiferromagnetic layer provided on a surface of the magnetization fixed layer opposite from the non-magnetic intermediate layer, and the antiferromagnetic layer fixing the magnetization of the magnetization fixed layer.

3. The magnetoresistance effect element as set forth in claim 1, wherein the first to fourth ferromagnetic films include any one of an iron (Fe) base alloy, a cobalt (Co) base alloy and a nickel (Ni) base alloy.

4. The magnetoresistance effect element as set forth in claim 1, wherein the first stacked body is any one of NiFe alloy/CoFe alloy, Fe base alloy/NiFe alloy, and Fe base alloy/Cope alloy and the second stacked body is any one of NiFe alloy/CoFe alloy, Fe base alloy/NiFe alloy, and Fe base alloy/CoFe alloy.

5. A magnetic head comprising a magnetoresistance effect element, the magnetoresistance effect element including:

a magnetization fixed layer in which a direction of magnetization is substantially fixed to one direction, the magnetization fixed layer having a first stacked body including first and second ferromagnetic films, the first and second ferromagnetic films in the first stacked body being ferromagnetically coupled to each other in the first stacked body;

a magnetization free layer in which a direction of magnetization varies in response to an external magnetic field, the magnetization free layer having a second stacked body including third and fourth ferromagnetic films, the third and fourth ferromagnetic films in the second stacked body being ferromagnetically coupled to each other in the second stacked body;

a non-magnetic intermediate layer provided between the magnetization fixed layer and the magnetization free layer;

a high conductive layer provided on a surface of the magnetization free layer opposite from the non-magnetic intermediate layer, the high conductive layer having a higher conductivity than those of the magnetization fixed layer and the magnetization free layer;

a resistance of the magnetoresistance effect element varying in accordance with a relative angle between the direction of magnetization of the magnetization fixed layer and the direction of magnetization of the magnetization free layer; and

a sense current flowing to the magnetization fixed layer, the non-magnetic intermediate layer and the magnetization free layer in a direction substantially perpendicular to surfaces of those layers.

6. A magnetic recording and/or reproducing system comprising a magnetic head having a magnetoresistance effect element, the magnetoresistance effect element including:

a magnetization fixed layer in which a direction of magnetization is substantially fixed to one direction, the magnetization fixed layer having a first stacked body including first and second ferromagnetic films, the first and second ferromagnetic films in the first stacked body being ferromagnetically coupled to each other in the first stacked body;

a magnetization free layer in which a direction of magnetization varies in response to an external magnetic field, the magnetization free layer having a second stacked body including third and fourth ferromagnetic films, the third and fourth ferromagnetic films in the second stacked body being ferromagnetically coupled to each other in the second stacked body;

a non-magnetic intermediate layer provided between the magnetization fixed layer and the magnetization free layer;

a high conductive layer provided on a surface of the magnetization free layer opposite from the non-magnetic intermediate layer, the high conductive layer having a higher conductivity than those of the magnetization fixed layer and the magnetization free layer;

a resistance of the magnetoresistance effect element varying in accordance with a relative angle between the direction of magnetization of the magnetization fixed layer and the direction of magnetization of the magnetization free layer; and

a sense current flowing to the magnetization fixed layer, the non-magnetic intermediate layer and the magnetization free layer in a direction substantially perpendicular to surfaces of those layers.