US4897288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vialess shorting bars for magnetoresistive devices
Assignee: Micron Technology Inc
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Filing: 1988-03-15
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Granted: 1990-01-30
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Expires: 2008-03-15
Abstract
Abstract A magnetic solid state device, such as a magnetoresistive memory cell, includes first and second layers of magnetoresistive material. The first and second layers are separated by a third layer which prevents exchange coupling between the magnetic dipoles of the first and second layers. The first, second and third layers are formed as a strip. A fourth layer of a resistive material, such as nitrogen doped tantalum, overlies the first layer. The fourth layer includes spaced, raised portions over which electrically conductive material, such as TiW, may be formed on top of the raised portions.
Inventors
- 👤 Mark L. Jenson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:11
CPC Classifications
H; H10; H10N; H10N50/00; H10N50/01; G; G11; G11C; G11C11/00; G11C11/02; G11C11/14; G11C11/15
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
156 words
A method of forming a magnetoresistive thin film device on a solid state material surface, comprising: forming a first layer of a ferromagnetic, magnetoresistive material on said surface; forming a second layer over said layer, wherein said second layer will serve to separate said first layer from subsequent layers; forming a third layer of a ferromagnetic magnetoresistive material over said second layer, wherein said second layer is comprised of a material which will prevent exchange coupling between said first and third layers; forming a fourth layer over said third layer, said fourth layer including tantalum and nitrogen; forming a fifth layer over said fourth layer, said fifth layer being comprised of a conductive material; removing portions of each of said five layers so that a strip including all of said five layers results; protecting selected, spaced portions of the upper surface of said fifth layer; and removing the part of said fifth layer which is unprotected.
Claim 2
Independent Claim
156 words
A method of forming a magnetoresistive thin film device on a solid state material surface, comprising: forming a first layer of a ferromagnetic, magnetoresistive material on said surface; forming a second layer over said layer, wherein said second layer will serve to separate said first layer from subsequent layers; forming a third layer of a ferromagnetic magnetoresistive material over said second layer, wherein said second layer is comprised of a material which will prevent exchange coupling between said first and third layers; forming a fourth layer over said third layer, said fourth layer including tantalum and nitrogen; forming a fifth layer over said fourth layer, said fifth layer being comprised of a conductive material; removing portions of each of said five layers so that a strip including all of said five layers results; protecting selected, spaced portions of the upper surface of said fifth layer; and removing the part of said fifth layer which is unprotected.
Claim 3
Dependent Claim
56 words
The method of claim 1 wherein said removing of said part of said fifth layer which is not protected includes removing that part of said fourth layer which is adjacent said unprotected part of said fifth layer, so that said fourth layer has a raised portion at each of said spaced portions of said fifth layer.
References Cited (Backward Citations)
US3015807A
Cited
US3125743A
Cited
US3375503A
Cited
US3484756A
Cited
US3587069A
Cited
US3452334A
Cited
US3525023A
Cited
US3466632A
Cited
US3524173A
Cited
US3623038A
Cited
US3701983A
Cited
US3798623A
Cited
US3996575A
Cited
US4079360A
Cited
US4097802A
Cited
US4024489A
Cited
US4208725A
Cited
US4780848A
Cited
US4731757A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-29 | 1993-07-31 | 1994-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-29 | 1997-07-31 | 1998-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-29 | 2001-07-31 | 2002-01-30 | $7700.00 | Window Closed / Lapsed |