US3676867A
Expired / Lapsed
US
⏱️ 0.0 years remaining
USE OF MnAlGe IN MAGNETIC STORAGE DEVICES
Assignee: AT&T Inc
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Filing: 1970-12-07
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Granted: 1972-07-11
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Expires: 1990-12-07
Abstract
Abstract It has been found that vapor deposition of the ferromagnetic material MnAlGe onto a substrate will give a thin film having the easy direction of magnetization normal to the substrate. This unusual capability does not depend on epitaxial growth and, indeed, the preferred embodiment calls for the use of an amorphous substrate. This inherent property of MnAlGe makes it useful for the class of magnetic devices operating on the principle of the reversal of the direction of magnetization of isolated regions for the purpose of information storage.
Inventors
- 👤 Donald Dingley Bacon
- 👤 Ethan Allen Nesbitt
- 👤 Richard Curry Sherwood
- 👤 Jack Harry Wernick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 10:31
CPC Classifications
C; C22; C22C; C22C28/00; C23; C23C; C23C14/00; C23C14/06; C23C14/14; G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10582; G11B11/10586; H; H01; H01F; H01F10/00; H01F10/08; H01F10/10; H01F10/12
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
56 words
An article comprising a film of a ferromagnetic material which is vapor deposited onto a substrate, said film having the easy direction of magnetization substantially normal to the surface of said film, characterized in that said film is comprised of an essentially homogeneous composition having atomic proportions indicated by the formula: Mn0.8 1.2Al0.8 1.2Ge0.8 1.2 .
Claim 2
Dependent Claim
56 words
An article comprising a film of a ferromagnetic material which is vapor deposited onto a substrate, said film having the easy direction of magnetization substantially normal to the surface of said film, characterized in that said film is comprised of an essentially homogeneous composition having atomic proportions indicated by the formula: Mn0.8 1.2Al0.8 1.2Ge0.8 1.2 .
Claim 3
Dependent Claim
15 words
The article of claim 1 in which said formula is: Mn0.9 1.1Al0.9 1.1Ge0.9 1.1 .
Claim 4
Dependent Claim
28 words
The article of claim 1 in which said vapor deposition is accomplished by sputtering onto an amorphous substrate maintained at a temperature of from 300* to 600* C.
Claim 5
Dependent Claim
26 words
The article of claim 1 in which first means are provided for the storage of information by affecting the magnetization of selected portions of said film.
Claim 6
Dependent Claim
25 words
The article of claim 4 in which second means are provided for the retrieval of said information by sensing said selected portions of said film.
Claim 7
Dependent Claim
25 words
The article of claim 5 in which said second means include providing for transmitting a substantial fraction of plane-polarized radiation incident on said film therethrough.
Claim 8
Dependent Claim
20 words
The article of claim 6 in which said sEcond means depends upon the degree of rotation of said transmitted beam.
Claim 9
Dependent Claim
23 words
The article of claim 5 in which said second means depends upon the degree of rotation of plane-polarized radiation incident on said film.
Claim 10
Dependent Claim
40 words
The article of claim 4 in which said first means include provision for heating selected localized regions of said film to reduce the coercivity of said film and for simultaneously applying a magnetic field to reverse magnetization of said regions.
Claim 11
Dependent Claim
19 words
The article of claim 9 in which the range of said heating includes the Curie temperature of the material.
References Cited (Backward Citations)
US3065071A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-11 | 1976-01-10 | 1976-07-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-11 | 1980-01-10 | 1980-07-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-11 | 1984-01-10 | 1984-07-11 | $7700.00 | Window Closed / Lapsed |