EP0216610A1
Expired / Lapsed
EP
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Vertical magnetic recording medium with multilayered magnetisable film structure
Assignee: International Business Machines Corp
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Filing: 1986-09-19
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Granted: —
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Expires: 2006-09-19
Abstract
Abstract The present invention relates to a magnetic recording medium of the type which comprises a substrate (51) and a magnetisable film structure (50) formed from a plurality of films supported on the substrate. A medium in accordance with the invention is characterised in that each film comprises a layer (30 - 38) of non-magnetisable material and a layer (40 - 48) of a magnetisable metal alloy including cobalt and chromium formed on the layer of non-magnetisable material, whereby the magnetisable film structure has perpendicular magnetic anisotropy.
Inventors
- 👤 Clifford John Robinson
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 20:20
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/66; G11B5/676; G11B5/678; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9265; Y10S428/928; Y10T; Y10T428/00; Y10T428/12; Y10T428/12431; Y10T428/12438; Y10T428/12465; Y10T428/12493; Y10T428/12535; Y10T428/12556; Y10T428/12569; Y10T428/12597; Y10T428/12625; Y10T428/12674; Y10T428/12736; Y10T428/12743; Y10T428/1275; Y10T428/12771; Y10T428/12861; Y10T428/12931; Y10T428/12937; Y10T428/12944; Y10T428/12951
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
72 words
A magnetic recording medium comprising a substrate (51) and a magnetisable film structure (50) formed from a plurality of films (20 - 28) supported on said substrate, characterised in that each film comprises a layer (30 - 38) of non-magnetisable material and a layer (40 - 48) of a magnetisable metal alloy including cobalt and chromium formed on said layer of non-magnetisable material, whereby said magnetisable film structure has perpendicular magnetic anisotropy.
Claim 2
Dependent Claim
72 words
A magnetic recording medium comprising a substrate (51) and a magnetisable film structure (50) formed from a plurality of films (20 - 28) supported on said substrate, characterised in that each film comprises a layer (30 - 38) of non-magnetisable material and a layer (40 - 48) of a magnetisable metal alloy including cobalt and chromium formed on said layer of non-magnetisable material, whereby said magnetisable film structure has perpendicular magnetic anisotropy.
Claim 3
Dependent Claim
30 words
A medium according to claim 1 characterised in that said magnetisable metal alloy comprises cobalt, chromium and an element from the group consisting of tantalum, niobium, tungsten, titanium and vanadium.
Claim 4
Independent Claim
36 words
A medium according to either of the preceding claims characterised in that said layer of non-magnetisable material and said layer of magnetisable metal alloy in each of said films are alloys consisting of the same elements.
Claim 5
Independent Claim
29 words
A medium according to any one of the preceding claims characterised in that said layer of non-magnetisable material and said layer of magnetisable metal alloy are sputter deposited layers.
Claim 6
Independent Claim
24 words
A medium according to any one of the preceding claims characterised in that it comprises a protective overcoat formed on said magnetisable film structure.
Claim 7
Independent Claim
37 words
A medium according to any one of the preceding claims characterised in that it comprises a soft magnetisable underlayer (60) between said substrate (61) and said magnetisable film structure (50) for providing a magnetic flux return path.
Claim 8
Dependent Claim
83 words
A medium according to claim 6 characterised in that said soft magnetisable underlayer is a film structure formed from a plurality of films (70 - 74), each film in said underlayer film structure comprising a layer of non-magnetisable material and a layer of a magnetisable metal alloy including cobalt and chromium formed on said layer of non-magnetisable material, each layer of magnetisable metal alloy in said underlayer film structure being sufficiently thin such that said underlayer film structure exhibits no perpendicular magnetic anisotropy.
Claim 9
Dependent Claim
36 words
A medium according to claim 7 characterised in that said magnetisable metal alloy in said underlayer film structure comprises cobalt, chromium and an element selected from the group consisting of tantalum, niobium, tungsten, titanium and vanadium.
Claim 10
Dependent Claim
41 words
A medium according to claim 7 or claim 8 characterised in that said layer of non-magnetisable material and said layer of magnetisable metal alloy in each of said films in said underlayer film structure are alloys consisting of the same elements.
Claim 11
Dependent Claim
26 words
A medium according to claim 9 characterised in that said alloys in said magnetisable film structure and said underlayer film structure consist of the same elements.
References Cited (Backward Citations)
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