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US5043693A
Expired / Lapsed
US
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Heterogeneous magnetoresistive layer
Assignee: United States Department of the Navy
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Filing: 1990-08-13
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Granted: 1991-08-27
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Expires: 2010-08-13
Abstract
Abstract A magnetoresistive material includes discrete units of magnetostrictive mrial separated from one another by one or more gaps. In one class of embodiments, magnetostrictive particles are embedded in a phase-separated nonmagnetostrictive matrix. In one embodiment a magnetoresistive article is made by co-sputtering particles of a magnetrostrictive material and a quantity of a nonmagnetostrictive material onto an nonmagnetostrictive substrate. The magnetostrictive particles are spaced from one another by distances in the range of 10 to 100 angstroms. In another embodiment, a magnetoresistive article is made by employing relatively large magnetostrictive electrodes separated by a small gap on a nonmagnetostrictive substrate. Magnetic field sensors employing such articles are also provided.
Inventors
- 👤 Alan S. Edelstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 11:00
CPC Classifications
H; H01; H01F; H01F10/00; H01F10/007; B; B82; B82Y; B82Y25/00; H10; H10N; H10N50/00; H10N50/10; H10N50/80; H10N50/85
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
107 words
A heterogenous magnetoresistive material formed by co-sputtering a magnetostrictive material and a nonmagnetostrictive material, comprising separate particles or agglomerations of said magnetostrictive material embedded in a phase-separated matrix of said nonmagnetostrictive material, said particles or agglomerations being spaced from one another by gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said nonmagnetostrictive material having a sufficiently higher resistance than said magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetoresistive material.
Claim 2
Dependent Claim
107 words
A heterogenous magnetoresistive material formed by co-sputtering a magnetostrictive material and a nonmagnetostrictive material, comprising separate particles or agglomerations of said magnetostrictive material embedded in a phase-separated matrix of said nonmagnetostrictive material, said particles or agglomerations being spaced from one another by gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said nonmagnetostrictive material having a sufficiently higher resistance than said magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetoresistive material.
Claim 3
Dependent Claim
27 words
The heterogeneous magnetoresistive material described in claim 1 wherein said magnetoresistive material is formed by co-sputtering particles of a magnetostrictive material and particles of a nonmagnetostrictive material.
Claim 4
Dependent Claim
15 words
The heterogeneous magnetoresistive material described in claim 1 wherein said nonmagnetostrictive material is a ceramic.
Claim 5
Dependent Claim
18 words
The heterogeneous magnetoresistive material described in claim 1 wherein said matrix of nonmagnetostrictive material is an amorphous material.
Claim 6
Dependent Claim
18 words
The heterogeneous magnetoresistive material described in claim 1 wherein said matrix of nonmagnetostrictive material is a crystalline material.
Claim 7
Dependent Claim
27 words
The heterogeneous magnetoresistive material described in claim 1 wherein: said particles of magnetostrictive material include particles of nickel, and said matrix of nonmagnetostrictive material includes silicon dioxide.
Claim 8
Dependent Claim
20 words
The heterogeneous magnetoresistive material described in claim 1 wherein said separate particles of magnetostrictive material includes two different magnetostrictive materials.
Claim 9
Dependent Claim
20 words
The heterogeneous magnetoresistive material described in claim 1 wherein said separate particles of magnetostrictive material consists essentially of one material.
Claim 10
Dependent Claim
15 words
The heterogeneous magnetoresistive material described in claim 3 wherein said nonmagnetostrictive material is boron nitride.
Claim 11
Dependent Claim
19 words
A heterogeneous magnetoresistive article, comprising a quantity of magnetoresistive material described in claim 1 deposited on a nonmagnetostrictive substrate.
Claim 12
Dependent Claim
33 words
The heterogeneous magnetoresistive article described in claim 10 wherein said magnetoresistive material is formed by co-sputtering particles of a magnetostrictive material and a quantity of a phase-separated nonmagnetostrictive material on a nonmagnetostrictive substrate.
Claim 13
Dependent Claim
13 words
The heterogeneous magnetoresistive article described in claim 10 wherein said substrate is glass.
Claim 14
Dependent Claim
25 words
The heterogeneous magnetoresistive materials described in claim 1, wherein said separate particles of magnetostrictive material have a size range of from 10 to 1,000 Angstroms.
Claim 15
Dependent Claim
16 words
The heterogeneous magnetostrictive material of claim 1, wherein said nonmagnetostrictive material is an insulator or semiconductor.
Claim 16
Dependent Claim
24 words
The heterogenous magnetostrictive material of claim 1, wherein most of said magnetostrictive material is included as said agglomerations having sizes larger than said gaps.
Claim 17
Dependent Claim
112 words
A sensor for detecting a magnetic field, said sensor having a heterogeneous structure comprising: an insulating substrate, a plurality of magnetostrictive electrodes supported by the insulating substrate and spaced from one another by gaps, filled by said insulating substrate, which are changed in size by the application of a magnetic field to the electrodes, said insulating substrate having a sufficiently higher resistance than said magnetostrictive electrodes so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling to dominates the resistivity of said magnetoresistive material, the size of said gaps being modulated in the range of from 10 to 150 angstroms.
Claim 18
Dependent Claim
112 words
A sensor for detecting a magnetic field, said sensor having a heterogeneous structure comprising: an insulating substrate, a plurality of magnetostrictive electrodes supported by the insulating substrate and spaced from one another by gaps, filled by said insulating substrate, which are changed in size by the application of a magnetic field to the electrodes, said insulating substrate having a sufficiently higher resistance than said magnetostrictive electrodes so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling to dominates the resistivity of said magnetoresistive material, the size of said gaps being modulated in the range of from 10 to 150 angstroms.
Claim 19
Dependent Claim
13 words
The sensor described in claim 16 wherein said substrate is composed of glass.
Claim 20
Dependent Claim
13 words
The sensor described in claim 16 said magnetostrictive electrodes are composed of nickel.
Claim 21
Dependent Claim
16 words
The sensor described in claim 16, wherein said gap is modulated between 10 and 100 angstroms.
Claim 22
Dependent Claim
13 words
The sensor described in claim 16 wherein said substrate is a nonmagnetostrictive material.
Claim 23
Dependent Claim
119 words
A heterogeneous magnetoresistive material comprised of separate, co-sputtered particles or agglomerations of particles of magnetostrictive material having a magnetostrictivity of one sign embedded in a magnetostrictive matrix having a magnetostrictivity of opposite sign, said particles or agglomerations of particles being separated by gaps filled with said magnetostrictive matrix, said gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said magnetostrictive matrix material having a sufficiently higher resistance than said particles or agglomerations of magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetoresistive material.
Claim 24
Dependent Claim
119 words
A heterogeneous magnetoresistive material comprised of separate, co-sputtered particles or agglomerations of particles of magnetostrictive material having a magnetostrictivity of one sign embedded in a magnetostrictive matrix having a magnetostrictivity of opposite sign, said particles or agglomerations of particles being separated by gaps filled with said magnetostrictive matrix, said gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said magnetostrictive matrix material having a sufficiently higher resistance than said particles or agglomerations of magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetoresistive material.
Claim 25
Dependent Claim
16 words
The heterogeneous magnetostrictive material of claim 21, wherein said magnetostrictive matrix is an insulator or semiconductor.
Claim 26
Independent Claim
128 words
A method for making a magnetoresistive material comprising the step of co-sputtering particles of a magnetostrictive material and a quantity of a phase-separated nonmagnetostrictive material onto a nonmagnetostrictive substrate to form a heterogenous magnetoresistive material comprising separate particles or agglomeration of said magnetostrictive material embedded in a phase-separated matrix of said nonmagnetostrictive material, said particles or agglomerations being spaced from one another by gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said nonmagnetostrictive material having a sufficiently higher resistance than said magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetostrictive material.
Claim 27
Independent Claim
128 words
A method for making a magnetoresistive material comprising the step of co-sputtering particles of a magnetostrictive material and a quantity of a phase-separated nonmagnetostrictive material onto a nonmagnetostrictive substrate to form a heterogenous magnetoresistive material comprising separate particles or agglomeration of said magnetostrictive material embedded in a phase-separated matrix of said nonmagnetostrictive material, said particles or agglomerations being spaced from one another by gaps having sizes in the range of 10 to 100 angstroms, which gaps are changed in size by the application of a magnetic field, said nonmagnetostrictive material having a sufficiently higher resistance than said magnetostrictive material so that changes in the size of said gaps significantly alter an electron tunneling current applied across said gaps and electron tunneling dominates the resistivity of said magnetostrictive material.
Claim 28
Dependent Claim
14 words
The method of claim 23, wherein said nonmagnetostrictive material is an insulator or semiconductor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-08-26 | 1995-02-25 | 1995-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-26 | 1999-02-25 | 1999-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-26 | 2003-02-25 | 2003-08-27 | $7700.00 | Window Closed / Lapsed |