EP0552890A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Magnetic sensor
Assignee: International Business Machines Corp
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Filing: 1993-01-14
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Granted: —
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Expires: 2013-01-14
Abstract
Abstract A magnetoresistive (MR) sensor 31 having electrically conductive lead structures 38,41 which are in electrical contact with the MR element 32 at spaced positions. The lead structures comprise a thin film layer of ruthenium, iridium or rhodium to serve as the principal current carrying element. A thin film overlayer or both a thin film underlayer and overlayer may be utilized to provide an adhesion layer for the principal current carrying element. Both the overlayer and underlayer are formed of a material taken from the group consisting of Ti and Ta.
Inventors
- 👤 James Kent Howard
- 👤 Chernyge Hwang
- 👤 James Hsi-Tang Lee
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 13:42
CPC Classifications
B; B82; B82Y; B82Y25/00; G; G01; G01R; G01R33/00; G01R33/02; G01R33/06; G01R33/09; G01R33/093; G11; G11B; G11B5/00; G11B5/127; G11B5/33; G11B5/39; G11B5/3903
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
91 words
A magnetic sensor comprising a layer of magnetoresistive material formed on a substrate; and a plurality of electrically conductive lead structures electrically contacting said layer of magnetoresistive material at spaced positions, each said electrically conductive lead structure comprising a layer of a material selected from the group consisting of ruthenium, iridium and rhodium, whereby, when a signal output means is connected between two of said electrically conductive lead structures, resistance changes in said magnetoresistive material responsive to magnetic fields which are intercepted by said layer of magnetoresistive material can be detected.
Claim 2
Dependent Claim
42 words
A sensor as claimed in claim 1 wherein each said electrically conductive lead structure further comprises an overlayer formed of a material taken from the group consisting of titanium and tantalum, said overlayer being coextensive with said layer in said lead structure.
Claim 3
Dependent Claim
42 words
A sensor as claimed in claim 2 wherein each said electrically conductive lead structure further comprises an underlayer formed of a material taken from the group consisting of titanium and tantalum, said underlayer being coextensive with said layer in said lead structure.
Claim 4
Dependent Claim
24 words
A sensor as claimed in claim 2 or claim 3 wherein said layer is 1000-5000 angstroms thick and said overlayer is 25-200 angstroms thick.
Claim 5
Dependent Claim
25 words
A magnetic sensor as claimed in claim 3 wherein said layer is 1000-5000 angstroms thick and said overlayer and said underlayer are 25-200 angstroms thick.
Claim 6
Dependent Claim
15 words
A magnetic sensor as claimed in claim 1 wherein said layer is 1000-5000 angstroms thick.
Claim 7
Dependent Claim
159 words
A magnetic storage system comprising: a magnetic storage medium having a plurality of tracks for recording of data; a magnetic transducer maintained in a closely spaced position relative to said magnetic storage medium during relative motion between said magnetic transducer and said magnetic storage medium, said magnetic transducer further comprising: a layer of magnetoresistive material formed on a substrate; and a plurality of electrically conductive lead structures electrically contacting said layer of magnetoresistive material at spaced positions, each said electrically conductive lead structure comprising a layer of a material selected from the group consisting of ruthenium, iridium and rhodium; actuator means coupled to said magnetic transducer for moving said magnetic transducer to selected tracks on said magnetic storage medium; and means coupled between two of said electrically conductive lead structures for detecting resistance changes in said magnetoresistive material responsive to magnetic fields representative of data bits recorded in said magnetic storage medium intercepted by said layer of magnetoresistive material.
Claim 8
Dependent Claim
42 words
A system as claimed in claim 7 wherein each said electrically conductive lead structure further comprises an overlayer formed of a material taken from the group consisting of titanium and tantalum, said overlayer being coextensive with said layer in said lead structure.
Claim 9
Dependent Claim
42 words
A system as claimed in claim 8 wherein each said electrically conductive lead structure further comprises an underlayer formed of a material taken from the group consisting of titanium and tantalum, said underlayer being coextensive with said layer in said lead structure.
Claim 10
Dependent Claim
21 words
A system as claimed in claim 9 wherein said layer is 1000-5000 angstroms thick and said overlayer is 25-200 angstroms thick.
Claim 11
Dependent Claim
17 words
A system as claimed in claim 10 wherein said overlayer and said underlayer is 25-200 angstroms thick.
Claim 12
Dependent Claim
14 words
A system as claimed in claim 7 wherein said layer is 1000-5000 angstroms thick.
References Cited (Backward Citations)
No citation records indexed.
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