Magneto-resistance effect element, magneto-resistance effect head, magneto-resistance transducer system, and magnetic storage system

• US 6,934,132 B2
• Filed: 07/30/2001
• Issued: 08/23/2005
• Est. Priority Date: 08/03/2000
• Status: Expired due to Term

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ishi, Tsutomu, Ishiwata, Nobuyuki, Fujikata, Junichi, Mori, Shigeru, Nakada, Masafumi, Nagahara, Kiyokazu, Hayashi, Kazuhiko, Ohashi, Keishi, Ishihara, Kunihiko
• Primary Examiner(s): KLIMOWICZ, WILLIAM JOSEPH
• Application Number:
  US09/916,529
• Publication Number:
  US 20020097540A1
• Time in Patent Office: 1,485 Days
• Field of Search: 360/324.12, 360/327.1, 3603273-32733, 360/324.2
• US Class Current: 360/324.12
• 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 31/3171 BER [Bit Error Rate] test
• CPC Class Codes: G01R 33/093 using multilayer structures, e.g. giant magnetoresistance sensors thin magnetic films H01F10/00
• 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 5/39 using magneto-resistive devices or effects
• 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 5/3909 Arrangements using a magnetic tunnel junction
• CPC Class Codes: G11B 5/3932 Magnetic biasing films
• CPC Class Codes: G11B 5/3967 Composite structural arrangements of transducers, e.g. inductive write and magnetoresistive read G11B5/3906 takes precedence
• 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

Abstract

A magneto-resistance effect head is provided with a lower conductive layer which is provided with a recessed portion, and a vertical bias layer is provided in the recessed portion. A free layer is provided on the lower conductive layer. On the free layer, layered in the following order are the non-magnetic layer, the fixed layer, the fixing layer, and the upper layer so as not to be placed inmediately above the vertical bias layer. The non-magnetic layer, the fixed layer, the fixing layer, and the upper layer are buried in an insulation layer. Furthermore, an upper conductive layer is provided on the upper layer and the insulation layer. In the direction of the magnetic field applied by the vertical bias layer, the free layer is made greater in length than the fixed layer and the free layer is disposed in proximity to the vertical bias layer with the distance between the fixed layer and the vertical bias layer remaining unchanged.

Claims

1. A magneto-resistance effect element comprising:

a lower conductive layer;

a free layer provided on the lower conductive layer and having an orientation of magnetization varied by a magnetic field applied thereto, said free layer thereby acting as a magnetic sensing layer changing the orientation of magnetization in accordance with the direction and magnitude of the magnetic field;

a non-magnetic layer provided on top of the free layer;

a fixed layer provided on the non-magnetic layer and having a pinned orientation of magnetization;

a vertical bias layer, provided on said lower conductive layer and not underneath said non-magnetic layer, for applying a magnetic field to said free layer, said free layer being patterned to make an end portion thereof overlap that of said vertical bias layer, and said free layer is greater in length in the direction of a magnetic field applied thereto by said vertical bias layer than said fixed layer, and a sense current for detecting a change in electrical resistance of said non-magnetic layer flows substantially in perpendicular relation to said non-magnetic layer, and

an underlying layer for said free layer provided under said free layer, and said underlying layer for said free layer being provided on said vertical bias layer and extending on said vertical bias layer beyond said overlapping portion of said free layer.

2. The magneto-resistance effect element according to claim 1, wherein said lower conductive layer has a recessed portion on an upper surface thereof, and said vertical bias layer is provided so as to allow at least part thereof to be buried in said recessed portion.

3. The magneto-resistance effect element according to claim 1, further comprising a vertical bias layer protective layer provided on said vertical bias layer, and said vertical bias layer protective layer being in contact with said vertical bias layer, and said vertical bias layer protective layer being in contact with at least one of said free layer and said underlying layer for said free layer.

4. A magneto-resistance effect element comprising:

a lower conductive layer;

a free layer provided on the lower conductive layer and having an orientation of magnetization varied by a magnetic field applied thereto;

a non-magnetic layer provided on the free layer;

a fixed layer provided on the non-magnetic layer and having a pinned orientation of magnetization; and

a vertical bias layer, provided on said lower conductive layer and not underneath said non-magnetic layer, for applying a magnetic field to said free layer, said free layer being patterned to make an end portion thereof overlap that of said vertical bias layer, and said free layer is greater in length in the direction of a magnetic field applied thereto by said vertical bias layer than said fixed layer, and a sense current for detecting a change in electrical resistance of said non-magnetic layer flows substantially in perpendicular relation to said non-magnetic layer, and

an underlying layer for said vertical bias layer, wherein said vertical bias layer is provided so as to allow at least part thereof to be buried in a recessed portion on an upper surface of said lower conductive layer so as to provide a gradual slope to an end portion of said underlying layer for said vertical bias layer.

5. The magneto-resistance effect element according to claim 4, wherein said lower conductive layer has a recessed portion on an upper surface thereof, and said vertical bias layer is provided so as to allow at least part thereof to be buried in said recessed portion.