US4434476A
Expired / Lapsed
US
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Magnetic bubble memory device and method for operating the same
Assignee: Fujitsu Ltd
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Filing: 1982-08-17
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Granted: 1984-02-28
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Expires: 2002-08-17
Abstract
Abstract A magnetic bubble memory device includes: a magnetic layer with a first region having an easy axis of magnetization extending in a certain direction and a second region surrounding the first region and having an easy axis of magnetization substantially perpendicular to that of the first region, said first region defining a plurality of bubble propagation patterns; and a replicate gate with a stretch conductor pattern, to which an electric current is applied so as to stretch a bubble between said propagation patterns, and a cutting pattern formed in the second region between the propagation patterns and adapted to lower the bubble collapse field so as to cut the stretched domain. The replicate gate is operated by applying an operating current pulse to the stretch conductor pattern, said operating pulse including a stretch pulse for stretching the bubble and a cut pulse, following the stretch pulse, for cutting the stretched domain.
Inventors
- 👤 Kazuo Matsuda
- 👤 Makoto Ohashi
- 👤 Yoshio Satoh
- 👤 Tsutomu Miyashita
- 👤 Kazunari Komenou
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:34
CPC Classifications
G; G11; G11C; G11C19/00; G11C19/02; G11C19/08; G11C19/0858; G11C19/0875; G11C19/0883
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
112 words
A magnetic bubble memory device comprising a magnetic layer including a first region with an easy axis of magnetization extending in a certain direction, and a second region surrounding said first region and having an easy axis of magnetization substantially perpendicular to that of the first region, said first region defining a plurality of bubble propagation patterns, and a replicate gate including a stretch conductor pattern, to which an electric current is applied so as to stretch a bubble between said propagation patterns, and a cutting pattern formed in said second region between said propagation patterns and adapted to lower the bubble collapse field so as to cut the stretched magnetic domain.
Claim 2
Dependent Claim
112 words
A magnetic bubble memory device comprising a magnetic layer including a first region with an easy axis of magnetization extending in a certain direction, and a second region surrounding said first region and having an easy axis of magnetization substantially perpendicular to that of the first region, said first region defining a plurality of bubble propagation patterns, and a replicate gate including a stretch conductor pattern, to which an electric current is applied so as to stretch a bubble between said propagation patterns, and a cutting pattern formed in said second region between said propagation patterns and adapted to lower the bubble collapse field so as to cut the stretched magnetic domain.
Claim 3
Dependent Claim
26 words
A device according to claim 1, wherein said cutting pattern is defined by a region having the same easy axis as that of said first region.
Claim 4
Dependent Claim
37 words
A device according to claim 2, wherein said first region and said region defining the cutting pattern are regions in which ions are not implanted, and said second region is a region in which ions are implanted.
Claim 5
Dependent Claim
12 words
A device according to claim 2, wherein said cutting pattern is V-shaped.
Claim 6
Dependent Claim
16 words
A device according to claim 1, wherein said cutting pattern is defined by a paramagnetic region.
Claim 7
Dependent Claim
42 words
A device according to claim 5, wherein said first region is a region in which ions are not implanted, said second region is a region in which ions are implanted, and said paramagnetic region is a region in which ions are over-implanted.
Claim 8
Independent Claim
158 words
A method for operating a magnetic bubble memory device, said magnetic bubble memory device comprising: a magnetic layer including a first region having an easy axis of magnetization extending in a certain direction, and a second region surrounding said first region and having an easy axis of magnetization substantially perpendicular to that of the first region, said first region defining a plurality of bubble propagation patterns, and a replicate gate including a stretch conductor pattern, to which an electric current is applied so as to stretch a bubble between said propagation patterns, and a cutting pattern formed in said second region between said propagation patterns and adapted to lower the bubble collapse field so as to cut the stretched magnetic domain, said method comprising applying an operating current pulse to said stretch conductor pattern, said operating pulse including a stretch pulse for stretching the bubble and a cut pulse, following said stretch pulse, for cutting the stretched domain.
Claim 9
Independent Claim
158 words
A method for operating a magnetic bubble memory device, said magnetic bubble memory device comprising: a magnetic layer including a first region having an easy axis of magnetization extending in a certain direction, and a second region surrounding said first region and having an easy axis of magnetization substantially perpendicular to that of the first region, said first region defining a plurality of bubble propagation patterns, and a replicate gate including a stretch conductor pattern, to which an electric current is applied so as to stretch a bubble between said propagation patterns, and a cutting pattern formed in said second region between said propagation patterns and adapted to lower the bubble collapse field so as to cut the stretched magnetic domain, said method comprising applying an operating current pulse to said stretch conductor pattern, said operating pulse including a stretch pulse for stretching the bubble and a cut pulse, following said stretch pulse, for cutting the stretched domain.
Claim 10
Dependent Claim
24 words
A method according to claim 7, wherein said operating pulse further comprises an additional stretch pulse, following said cut pulse, for stabilizing the bubbles.
References Cited (Backward Citations)
US4249249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-02-27 | 1987-08-29 | 1988-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-27 | 1991-08-29 | 1992-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-27 | 1995-08-29 | 1996-02-28 | $7700.00 | Window Closed / Lapsed |