US6201673B1
Expired / Lapsed
US
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System for biasing a synthetic free layer in a magnetoresistance sensor
Assignee: Western Digital Technologies Inc
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Filing: 1999-04-02
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Granted: 2001-03-13
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Expires: 2019-04-02
Abstract
Abstract A system and method for providing a magnetoresistive head is disclosed. The method and system include providing a spin valve including a synthetic free layer. The synthetic free layer includes a ferromagnetic layer. The method and system also include providing an antiferromagnetic biasing layer exchange coupled to a first portion of the ferromagnetic layer. The antiferromagnetic biasing layer magnetically biases the synthetic free layer to ensure the single domain structure and reduce noise.
Inventors
- 👤 Robert E. Rottmayer
- 👤 Jain-Gang Zhu
- 👤 Kenneth Everett Knapp
- 👤 Yiming Huai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:50
CPC Classifications
B; B82; B82Y; B82Y10/00; G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/3906; G11B5/3929; G11B5/3932
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
57 words
A magnetoresistive head comprising: a spin valve including a synthetic free layer, the synthetic free layer including a ferromagnetic layer and a second ferromagnetic layer antiferromagnetically coupled to the ferromagnetic layer; and an antiferromagnetic biasing layer exchange coupled to a first portion of the ferromagnetic layer; wherein the antiferromagnetic biasing layer magnetically biases the synthetic free layer.
Claim 2
Dependent Claim
57 words
A magnetoresistive head comprising: a spin valve including a synthetic free layer, the synthetic free layer including a ferromagnetic layer and a second ferromagnetic layer antiferromagnetically coupled to the ferromagnetic layer; and an antiferromagnetic biasing layer exchange coupled to a first portion of the ferromagnetic layer; wherein the antiferromagnetic biasing layer magnetically biases the synthetic free layer.
Claim 3
Dependent Claim
23 words
The magnetoresistive head of claim 1 wherein a portion of the antiferromagnetic biasing layer is above the first portion of the ferromagnetic layer.
Claim 4
Dependent Claim
14 words
The magnetoresistive head of claim 1 wherein the antiferromagnetic biasing layer further includes IrMn.
Claim 5
Dependent Claim
19 words
The magnetoresistive head of claim 1 further comprising: a capping layer on a second portion of the ferromagnetic layer.
Claim 6
Dependent Claim
14 words
The magnetoresistive head of claim 4 wherein the capping layer is an insulating layer.
Claim 7
Dependent Claim
15 words
The magnetoresistive head of claim 5 wherein the insulating layer further includes an AlN layer.
Claim 8
Dependent Claim
45 words
The magnetoresistive head of claim 1 further comprising: a third ferromagnetic layer disposed between the first portion of the ferromagnetic layer and the antiferromagnetic biasing layer, the third ferromagnetic layer for magnetically coupling the antiferromagnetic biasing layer to the first portion of the ferromagnetic layer.
Claim 9
Dependent Claim
38 words
The magnetoresistive head of claim 7 further including: a first shield; a second shield; and a gap, the gap separating either the first shield or the second shield from the spin valve and from the antiferromagnetic biasing layer.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-03-12 | 2004-09-11 | 2005-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-03-12 | 2008-09-11 | 2009-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-03-12 | 2012-09-11 | 2013-03-13 | $7700.00 | Window Closed / Lapsed |