EP0158338A2
Expired / Lapsed
EP
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Perpendicular magnetic recording medium
Assignee: Hitachi Ltd
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Filing: 1985-04-10
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Granted: —
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Expires: 2005-04-10
Abstract
Abstract Disclosed is a perpendicular magnetic recording medium wherein an under layer (2) made of a material containing Si and/or Ge as its principal ingredient is deposited on a substrate (1), and a perpendicular magnetic film (3) made of a Co-based alloy is deposited on the under layer. With the perpendicular magnetic recording medium, the perpendicular magnetic film has an enhanced degree of C-axis orientation, and the bond strength between the perpendicular magnetic film and the substrate is also enhanced when the substrate is non-metallic.
Inventors
- 👤 Masaaki Futamoto
- 👤 Yukio Honda
- 👤 Yasutaro Uesaka
- 👤 Kazuetsu Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 04:36
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/65; G11B5/656; G11B5/127; G11B5/1278; G11B5/66; G11B5/672; G11B5/73; G11B5/7368; G11B5/7377; G11B5/739; G11B5/73911; G11B5/73921; G11B5/73923; G11B5/73927; G11B2005/0002; G11B2005/0026; G11B2005/0029; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/12; Y10T428/12465; Y10T428/12493; Y10T428/12674
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
62 words
A perpendicular magnetic recording medium comprising a substrate, an under layer which is made of a material containing as its principal ingredient at least one element selected from the group consisting of Si and Ge and which is deposited on said substrate, and a perpendicular magnetic film which is made of a Co-based alloy and which is deposited on said under layer.
Claim 2
Dependent Claim
62 words
A perpendicular magnetic recording medium comprising a substrate, an under layer which is made of a material containing as its principal ingredient at least one element selected from the group consisting of Si and Ge and which is deposited on said substrate, and a perpendicular magnetic film which is made of a Co-based alloy and which is deposited on said under layer.
Claim 3
Dependent Claim
26 words
A perpendicular magnetic recording medium according to Claim 1, wherein a thickness of said under layer is at least 100 A and at most 1 µm.
Claim 4
Dependent Claim
26 words
A perpendicular magnetic recording medium according to Claim 2, wherein a thickness of said under layer is at least 150 Å and at most 1000 Å.
Claim 5
Dependent Claim
60 words
A perpendicular magnetic recording medium according to Claim 1, wherein said under layer is made of a material in which at least one element other than Si and Ge is added in such a range of amount that any structure other than a diamond structure and an amorphous structure does not appear in a crystal structure of said under layer.
Claim 6
Dependent Claim
60 words
A perpendicular magnetic recording medium according to Claim 2, wherein said under layer is made of a material in which at least one element other than Si and Ge is added in such a range of amount that any structure other than a diamond structure and an amorphous structure does not appear in a crystal structure of said under layer.
Claim 7
Dependent Claim
60 words
A perpendicular magnetic recording medium according to Claim 3, wherein said under layer is made of a material in which at least one element other than Si and Ge is added in such a range of amount that any structure other than a diamond structure and an amorphous structure does not appear in a crystal structure of said under layer.
Claim 8
Dependent Claim
31 words
A perpendicular magnetic recording medium according to Claim 1, wherein at least that surface of said substrate on which said under layer is formed is made of a soft magnetic material.
Claim 9
Dependent Claim
31 words
A perpendicular magnetic recording medium according to Claim 2, wherein at least that surface of said substrate on which said under layer is formed is made of a soft magnetic material.
Claim 10
Dependent Claim
31 words
A perpendicular magnetic recording medium according to Claim 3, wherein at least that surface of said substrate on which said under layer is formed is made of a soft magnetic material.
References Cited (Backward Citations)
No citation records indexed.
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