US 6,153,062 AGranted

Magnetoresistive sensor and head

AssigneeAlps Electric Co., Ltd.

InventorsMasamichi Saito, Toshinori Watanabe

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Abstract

PtMn films are used as antiferromagnetic layers of a dual spin-valve type magnetoresistive sensor. An exchange anisotropic magnetic field is achieved regardless of whether the PtMn film is formed over or under the pinned magnetic layer. Also, an effective exchange anisotropic magnetic field is produced even with heat treatment at a relatively low temperature. Alternatively, a PtMn film is used as an antiferromagnetic layer of a spin-valve film laminate. The use of a PtMn film enables a sufficient exchange anisotropic magnetic field to be produced even with a relatively low heat treatment temperature and a relatively small film thickness. Therefore, the number of total layers of the spin-valve film laminate can be increased to increase a magnetoresistance ratio, and a total thickness of the spin-valve film laminate can be made relatively small.

Claims15

Dependent claims

A method of manufacturing a magnetoresistive effect device, said method comprising:

forming a first antiferromagnetic layer made of a PtMn alloy on a substrate by a DC magnetron sputtering process,
forming a first pinned magnetic layer on said first antiferromagnetic layer in direct contact by a DC magnetron sputtering process,
forming a first non-magnetic electrically conductive layer on said first pinned magnetic layer,
forming a free magnetic layer on said first non-magnetic electrically conductive layer,
forming a second non-magnetic electrically conductive layer on said free magnetic layer,
forming a second pinned magnetic layer on said second non-magnetic electrically conductive layer by a DC magnetron sputtering process,
forming a second antiferromagnetic layer made of a PtMn alloy on said second pinned magnetic layer in direct contact by a DC magnetron sputtering process, and
heat-treating said first antiferromagnetic layer, said first pinned magnetic layer, said second pinned magnetic layer, and said second antiferromagnetic layer in a magnetic field at a temperature of between 210.degree. C. and 250.degree. C.

5 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/208,354Filed 10 Dec 1998 · division
Priority: JP 8-24204312 Sep 1996
Granted: 28 Nov 2000
Term ends: Not estimatedThe source records don’t support an estimate.

Classification18 codes

G01R 33/093
Magnetoresistive devices: using multilayer structures, e.g. giant magnetoresistance sensors
B82Y 10/00
Nanotechnology for information processing, storage or transmission
B82Y 25/00
Nanomagnetism
G11B 5/3903
Using magneto-resistive devices or effects: using magnetic thin film layers or their effects, the films being part of integrated structures