US5693426A
Expired / Lapsed
US
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Magnetic recording medium with B2 structured underlayer and a cobalt-based magnetic layer
Assignee: Carnegie Mellon University
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Filing: 1994-09-29
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Granted: 1997-12-02
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Expires: 2014-09-29
Abstract
Abstract The present invention provides a longitudinal magnetic recording media having a substrate, a Co or Co alloy based layer and an underlayer disposed between the substrate and the magnetic layer comprised of a material having a B2 ordered crystalline structure, preferably NiAl or FeAl. A thin Cr intermediate layer of about 1.0 nm to 5.0 nm thick may be positioned between the underlayer and the magnetic layer.
Inventors
- 👤 Li-Lien Lee
- 👤 David N. Lambeth
- 👤 David E. Laughlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:53
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/66; G11B5/676; G11B5/73; G11B5/7368; G11B5/7369; G11B5/737; G11B5/7371; G11B5/7377; G11B5/84; G11B5/8404; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/12; Y10T428/12465; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12896; Y10T428/12903; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
36 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 2
Dependent Claim
36 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 3
Dependent Claim
12 words
The recording medium recited in claim 1 wherein said material is NiAl.
Claim 4
Dependent Claim
12 words
The recording medium recited in claim 1 wherein said material is FeAl.
Claim 5
Dependent Claim
37 words
The recording medium recited in claim 1 wherein said material is selected from the group consisting of NiAl, AlCo, FeAl, FeTi, CoFe, CoTi, CoHf, CoZr, NiTi, CuBe, CuZn, AlMn, AlRe, AgMg and Al 2 FeMn 2 .
Claim 6
Dependent Claim
26 words
The recording medium recited in claim 4 wherein said underlayer is comprised of multiple layers of two or more of said materials with the B2 structure.
Claim 7
Dependent Claim
20 words
The recording medium recited in claim 1 further comprising a chromium intermediate layer interposed between said film and said underlayer.
Claim 8
Dependent Claim
26 words
The recording medium recited in claim 1 further comprising an overcoat disposed on said film, such that said film lies between said underlayer and said overcoat.
Claim 9
Dependent Claim
28 words
The recording medium recited in claim 7 further comprising an organic lubricant disposed on said overcoat such that said overcoat lies between said lubricant and said magnetic layer.
Claim 10
Dependent Claim
28 words
The recording medium recited in claim 8 further comprising an overlayer disposed on said magnetic layer such that said overlayer lies between said magnetic layer and said overcoat.
Claim 11
Dependent Claim
20 words
The recording medium recited in claim 1 wherein said magnetic layer has an epitaxial crystalline structure grown from said underlayer.
Claim 12
Dependent Claim
29 words
The recording medium recited in claim 1 further comprising an intermediate layer interposed between said magnetic layer and said underlayer to promote epitaxial crystalline growth of said magnetic layer.
Claim 13
Dependent Claim
37 words
In a magnetic recording medium having a substrate, an underlayer and a magnetic layer, the improvement comprising: said underlayer is comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said magnetic layer.
Claim 14
Dependent Claim
37 words
In a magnetic recording medium having a substrate, an underlayer and a magnetic layer, the improvement comprising: said underlayer is comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said magnetic layer.
Claim 15
Dependent Claim
36 words
The improvement recited in claim 12 wherein said material is selected from the group consisting of NiAl, AlCo, FeAl, FeTi, CoFe, CoTi, CoHf, CoZr, NiTi, CuBe, CuZn, AlMn, AlRe, AgMg and Al 2 FeMn 2 .
Claim 16
Dependent Claim
20 words
The improvement recited in claim 13 further comprising a chromium intermediate layer interposed between said magnetic layer and said underlayer.
Claim 17
Dependent Claim
18 words
The improvement recited in claim 14 wherein said intermediate layer is sufficiently thick to substantially cover said underlayer.
Claim 18
Dependent Claim
19 words
The improvement recited in claim 14 wherein said intermediate layer is about 1.0 nm to about 5.0 nm thick.
Claim 19
Dependent Claim
20 words
The improvement recited in claim 12 wherein said underlayer has a lattice constant ranging from 0.27 nm to 0.33 nm.
Claim 20
Dependent Claim
35 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of NiAl having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 21
Dependent Claim
35 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of NiAl having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 22
Dependent Claim
35 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of FeAl having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 23
Dependent Claim
35 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and, an underlayer comprised of FeAl having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 24
Dependent Claim
43 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and an underlayer between about 10 to 200 nm thick comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 25
Dependent Claim
43 words
A magnetic recording medium comprising: a substrate; a Co or Co alloy film forming a magnetic layer; and an underlayer between about 10 to 200 nm thick comprised of a material having a B2-ordered crystalline structure disposed between said substrate and said film.
Claim 26
Dependent Claim
44 words
In a magnetic recording medium having a substrate, an underlayer and a magnetic layer, the improvement comprising; said underlayer is comprised of a material having a B2-ordered crystalline structure between about 10 to 200 nm thick disposed between said substrate and said magnetic layer.
Claim 27
Dependent Claim
44 words
In a magnetic recording medium having a substrate, an underlayer and a magnetic layer, the improvement comprising; said underlayer is comprised of a material having a B2-ordered crystalline structure between about 10 to 200 nm thick disposed between said substrate and said magnetic layer.
Claim 28
Independent Claim
64 words
An apparatus for data storage comprising: a hard disk comprising, a substrate forming the disk, a Co or Co alloy film forming a magnetic layer, and, an underlayer comprised of material having a B2-ordered crystalline structure disposed between said substrate and said film; and, a magnetic transducer positioned in close proximity to said disk to record and read data to and from said disk.
Claim 29
Independent Claim
64 words
An apparatus for data storage comprising: a hard disk comprising, a substrate forming the disk, a Co or Co alloy film forming a magnetic layer, and, an underlayer comprised of material having a B2-ordered crystalline structure disposed between said substrate and said film; and, a magnetic transducer positioned in close proximity to said disk to record and read data to and from said disk.
Claim 30
Dependent Claim
31 words
The apparatus recited in claim 22 wherein said hard disk further comprises an intermediate layer interposed between said magnetic layer and said underlayer to promote epitaxial growth of said magnetic layer.
Claim 31
Dependent Claim
18 words
The apparatus recited in claim 23 wherein said intermediate layer comprises a chromium or chromium vanadium intermediate layer.
Claim 32
Dependent Claim
19 words
The apparatus recited in claim 22 wherein said magnetic layer has an epitaxial crystalline structure grown from said underlayer.
Claim 33
Independent Claim
42 words
A method of producing an epitaxial crystalline Co or Co alloy magnetic layer on a recording substrate, said method comprising: depositing material having a B2 structure on the substrate; and, growing the Co or Co alloy magnetic layer on the B2 structure.
Claim 34
Independent Claim
42 words
A method of producing an epitaxial crystalline Co or Co alloy magnetic layer on a recording substrate, said method comprising: depositing material having a B2 structure on the substrate; and, growing the Co or Co alloy magnetic layer on the B2 structure.
Claim 35
Dependent Claim
31 words
The method of claim 26, wherein said step of depositing further comprises depositing material having a B2 structure and a lattice structure which promotes epitaxial crystalline growth of the magnetic layer.
Claim 36
Dependent Claim
29 words
The method of claim 26, wherein said step of depositing further comprises depositing material having a B2 structure and a lattice constant comparable to that of the magnetic layer.
Claim 37
Dependent Claim
30 words
The method of claim 26, further comprising the step of interposing an intermediate layer between the underlayer and the magnetic layer to promote epitaxial crystalline growth of the magnetic layer.
Claim 38
Dependent Claim
30 words
The method of claim 29, wherein: said step of depositing further comprises depositing a NiAl or FeAl underlayer; and, said step of inteposing further comprises interposing a Cr intermediate layer.
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| 3.5 Years (Year 4) | 2000-12-01 | 2001-06-02 | 2001-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-01 | 2005-06-02 | 2005-12-02 | $3760.00 | Window Closed / Lapsed |
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