US3968481A
Expired / Lapsed
US
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Method of, and apparatus for, establishing self-biased single wall domains
Assignee: International Business Machines Corp
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Filing: 1974-07-25
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Granted: 1976-07-06
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Expires: 1994-07-25
Abstract
Abstract A method of and apparatus for providing single wall self-biased magnetic domains in a film of uniaxial magnetic material. In addition to the conventional uniaxial magnetic film for supporting the single wall domains, a bias film is located adjacent thereto. The material characteristics of the two films and their thicknesses are chosen such that the exchange coupling between the two films provides the effect of an external field for supporting the single wall domains.
Inventors
- 👤 Philip J. Grundy
- 👤 Yeong S. Lin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:44
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/085
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
91 words
A method of fabricating a self-biased structure for supporting and moving single wall magnetic domains comprising the steps of: depositing on a suitable substrate, adjacent layers of bias and storage layers, said bias layer comprising a uniaxial magnetic material of thickness h' and material length l', to maintain a single domain state, said storage layer of uniaxial magnetic material with thickness h and material length l, and providing domain propagating means adjacent said storage layer, wherein said parameters are chosen such that (h/l) > (h'/l' ) with (h'/l' ) ≦ 1.
Claim 2
Independent Claim
91 words
A method of fabricating a self-biased structure for supporting and moving single wall magnetic domains comprising the steps of: depositing on a suitable substrate, adjacent layers of bias and storage layers, said bias layer comprising a uniaxial magnetic material of thickness h' and material length l', to maintain a single domain state, said storage layer of uniaxial magnetic material with thickness h and material length l, and providing domain propagating means adjacent said storage layer, wherein said parameters are chosen such that (h/l) > (h'/l' ) with (h'/l' ) ≦ 1.
Claim 3
Dependent Claim
25 words
The process of claim 1 in which said bias layer is deposited on said substrate and said storage layer is deposited on said bias layer.
Claim 4
Dependent Claim
19 words
The process of claim 1 in which the ratio of h/l is in the range of 4 to 10.
Claim 5
Dependent Claim
25 words
The process of claim 1 in which l is approximately equal to l'1' and h' is in the range of 10 to 20% of h.
Claim 6
Dependent Claim
34 words
The process of claim 1 in which said propagation means is deposited above said substrate, said storage layer is deposited above said propagation means and said bias layer is deposited above said storage layer.
Claim 7
Dependent Claim
82 words
A self-biased single wall domain supporting structure comprising, a substrate, a storage layer of magnetic material with thickness h and material length l, capable of supporting stable single wall domains in a suitable external field, and a bias layer of uniaxial magnetic material exchange coupled to said storage layer of thickness h' and material length l' where h' is sufficiently small to maintain a single domain state and h'/l' < h/l, whereby said bias layer provides magnetic forces simulatiing said external field.
Claim 8
Dependent Claim
82 words
A self-biased single wall domain supporting structure comprising, a substrate, a storage layer of magnetic material with thickness h and material length l, capable of supporting stable single wall domains in a suitable external field, and a bias layer of uniaxial magnetic material exchange coupled to said storage layer of thickness h' and material length l' where h' is sufficiently small to maintain a single domain state and h'/l' < h/l, whereby said bias layer provides magnetic forces simulatiing said external field.
Claim 9
Dependent Claim
25 words
The apparatus of claim 6 in which said bias layer is deposited on said substrate and said storage layer is deposited on said bias layer.
Claim 10
Dependent Claim
13 words
The apparatus of claim 6 which further includes single wall domain propagating means.
Claim 11
Dependent Claim
12 words
The apparatus of claim 6 in which, 4 ≦ h/l ≦ 10
Claim 12
Dependent Claim
10 words
The apparatus of claim 9 in which, h'/l' ≦ 1.
Claim 13
Dependent Claim
10 words
The apparatus of claim 9 in which, h'/l' ≦ 0.5.
Claim 14
Dependent Claim
45 words
The apparatus of claim 6 which further includes single wall domain propagating means and in which, said bias layer is deposited on said substrate, said storage layer is deposited on said bias layer, said single wall domain propagating means is deposited on said storage layer.
Claim 15
Dependent Claim
12 words
The apparatus of claim 12 in which, 4 ≦ h/l ≦ 10.
Claim 16
Dependent Claim
10 words
The apparatus of claim 13 in which, h'/l' ≦ 1.
Claim 17
Dependent Claim
10 words
The apparatus of claim 12 in which, h'/l' ≦ 0.5.
Claim 18
Dependent Claim
37 words
The apparatus of claim 6 which further comprises a single wall domain propagating means deposited on said substrate, said storage layer deposited on said single wall domain propagating means, said bias layer deposited on said storage layer.
Claim 19
Dependent Claim
15 words
The apparatus of claim 16 in which, 4 ≦ h/l ≦ 10. h/l b 10.
Claim 20
Dependent Claim
10 words
The apparatus of claim 17 in which, h'/l' ≦ 1.
Claim 21
Dependent Claim
10 words
The apparatus of claim 17 in which, h'/l' ≦ 0.5.
References Cited (Backward Citations)
US3678478A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-07-06 | 1980-01-05 | 1980-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-06 | 1984-01-05 | 1984-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-06 | 1988-01-05 | 1988-07-06 | $7700.00 | Window Closed / Lapsed |