Patent US5344669A successfully refreshed from Google Patents.
US5344669A
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Method of manufacture for an improved magnetoresistive read transducer
Assignee: International Business Machines Corp
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Filing: 1993-09-23
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Granted: 1994-09-06
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Expires: 2013-09-23
Abstract
Abstract A magnetoresistive (MR) read transducer in which a layered structure comprising an MR layer, an antiferromagnetic material in direct contact with the MR layer and a thin layer of interdiffusion material in contact with the layer of antiferromagnetic material is subjected to a heating process to a temperature within a chosen temperature for a chosen time to form a magnetic interface between the antiferromagnetic material the MR layer. The magnetic interface produces a high level of exchange bias with the MR layer.
Inventors
- 👤 Mao-Min Chen
- 👤 Ching H. Tsang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:32
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903; G11B5/399
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
88 words
A method for making a magnetoresistive read transducer assembly comprising the steps of: providing a substrate; depositing a thin magnetoresistive layer of ferromagnetic material on said substrate; depositing a thin layer of antiferromagnetic material in direct contact with the magnetoresistive layer; depositing a thin layer of an interdiffusion material in contact with the layer of antiferromagnetic material; and heating said layered structure to form a magnetic interface between said antiferromagnetic material and said magnetoresistive layer whereby said magnetic interface produces an exchange bias field in said magnetoresistive layer.
Claim 2
Independent Claim
88 words
A method for making a magnetoresistive read transducer assembly comprising the steps of: providing a substrate; depositing a thin magnetoresistive layer of ferromagnetic material on said substrate; depositing a thin layer of antiferromagnetic material in direct contact with the magnetoresistive layer; depositing a thin layer of an interdiffusion material in contact with the layer of antiferromagnetic material; and heating said layered structure to form a magnetic interface between said antiferromagnetic material and said magnetoresistive layer whereby said magnetic interface produces an exchange bias field in said magnetoresistive layer.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said interdiffusion material comprises a noble metal.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein said noble metal is taken from the group consisting of gold, rhodium, platinum, palladium, and ruthenium.
Claim 5
Dependent Claim
27 words
The method of claim 1 wherein said magnetoresistive layer comprises an alloy of nickel and iron and said antiferromagnetic layer comprises an alloy of iron and manganese.
Claim 6
Dependent Claim
13 words
The method of claim 4 wherein said interdiffusion material comprises a noble metal.
Claim 7
Dependent Claim
23 words
The method of claim 5 wherein said noble metal is taken from the group consisting of gold, rhodium, platinum, and palladium, and ruthenium.
Claim 8
Dependent Claim
11 words
The method of claim 6 wherein said noble metal is gold.
Claim 9
Dependent Claim
35 words
The method of claim 7 wherein said heating step is conducted at a temperature within the range of about 220° to 320° C. for a time within the range of about 2 to 12 hours.
Claim 10
Dependent Claim
25 words
The method of claim 8 wherein said heating step is conducted at a temperature of about 240° C. for a time of about 7 hours.
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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) | 1997-09-05 | 1998-03-07 | 1998-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-05 | 2002-03-07 | 2002-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-05 | 2006-03-07 | 2006-09-06 | $7700.00 | Window Closed / Lapsed |