US5266418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic recording medium
Assignee: Sony Corp
•
Filing: 1990-08-28
•
Granted: 1993-11-30
•
Expires: 2010-08-28
Abstract
Abstract A magnetic recording medium having a magnetic thin film of a composition expressed as (Co a Pt b M c I M d II ) Ox (where a, b, c, d are atomic percent; and x is weight percent). In this composition, a+b+c+d=100, 0<a, 0<b≦50, 0<c≦20, 0<d≦20, 0<x≦10. M I is at least one element selected from P, Si and Ge; and M II is at least one element selected from B, Ga, Al, In, Sn and Sb. Such magnetic thin film is capable of retaining a large coercive force regardless of its thickness and can be formed without the necessity of raising the base temperature during deposition of a magnetic layer.
Inventors
- 👤 Kazuhiko Hayashi
- 👤 Akihiko Okabe
- 👤 Masatoshi Hayakawa
- 👤 Koichi Aso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:45
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/64; G11B5/65; G11B5/658; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/12; Y10T428/12465; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12875
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
68 words
A magnetic thin film for use as a recording medium having a composition of: (Co.sub.a Pt.sub.b M.sub.c.sup.I M.sub.d.sup.II) .sub.100-x Ox in which a, b, c, d are atomic percent; and x is weight percent, wherein a+b+c+d=100 0<a 0<b≦50 0<c≦20 0<d≦20 0<x≦10 and M I is at least one element selected from P, Si and Ge; and M II is at least one element selected from Ga and In.
Claim 2
Dependent Claim
68 words
A magnetic thin film for use as a recording medium having a composition of: (Co.sub.a Pt.sub.b M.sub.c.sup.I M.sub.d.sup.II) .sub.100-x Ox in which a, b, c, d are atomic percent; and x is weight percent, wherein a+b+c+d=100 0<a 0<b≦50 0<c≦20 0<d≦20 0<x≦10 and M I is at least one element selected from P, Si and Ge; and M II is at least one element selected from Ga and In.
Claim 3
Dependent Claim
72 words
A magnetic recording medium having, on a base thereof, a magnetic thin film of a composition expressed as (Co.sub.a Pt.sub.b M.sub.c.sup.I M.sub.d.sup.II) .sub.100-x Ox in which a, b, c, d are atomic percent; and x is weight percent, wherein a+b+c+d=100 0<a 0<b≦50 0<c≦20 0<d≦20 0<x≦10 and M I is at least one element selected from P, Si and Ge; and M II is at least one element selected from Ga and In.
Claim 4
Dependent Claim
72 words
A magnetic recording medium having, on a base thereof, a magnetic thin film of a composition expressed as (Co.sub.a Pt.sub.b M.sub.c.sup.I M.sub.d.sup.II) .sub.100-x Ox in which a, b, c, d are atomic percent; and x is weight percent, wherein a+b+c+d=100 0<a 0<b≦50 0<c≦20 0<d≦20 0<x≦10 and M I is at least one element selected from P, Si and Ge; and M II is at least one element selected from Ga and In.
Claim 5
Dependent Claim
21 words
A magnetic thin film according to claim 1, wherein the thickness thereof is in a range of 500 to 5000 angstroms.
Claim 6
Dependent Claim
21 words
A magnetic thin film according to claim 1, wherein the content x of oxygen is selectively set as 0<x≦6 weight percent.
References Cited (Backward Citations)
US4542062A
Cited
DE3216863A1
Cited
US4661418A
Cited
US4833044A
Cited
EP0167118A2
Cited
US4647507A
Cited
EP0261240A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-11-29 | 1997-05-31 | 1997-11-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-29 | 2001-05-31 | 2001-11-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-29 | 2005-05-31 | 2005-11-30 | $7700.00 | Window Closed / Lapsed |