Patent US4767516A successfully refreshed from Google Patents.
US4767516A
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Method for making magnetic recording media
Assignee: Sanyo Electric Co Ltd
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Filing: 1986-05-19
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Granted: 1988-08-30
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Expires: 2006-05-19
Abstract
Abstract A magnetic recording tape making process and apparatus is disclosed. The apparatus includes a first depositing station which utilizes a the sputtering process for depositing a seed layer on a substrate with an initial incident angle of about 5°, and a second depositing station for depositing, over the seed layer, an extended layer with an initial incident angle of about 45°. The seed layer has a thickness of about 0.01 micrometer, and is defined by young crystalline columns of magnetic material densely and perpendicularly formed on the substrate. The extended layer is defined by extended crystalline columns over the young crystalline columns through self-epitaxial growth. The completed magnetic film defined by the two layers has a high residual magnetization ratio MV/MH and also a high perpendicular coercivity Hcv.
Inventors
- 👤 Yoshio Nakatsuka
- 👤 Minoru Kume
- 👤 Daisuke Kishimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:15
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/84; G11B5/851
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
142 words
A method for making magnetic recording media comprising the steps of: a first depositing step for depositing, through a sputtering process, a seed layer defined by crystalline columns of magnetic material densely and perpendicularly formed on a substrate at a first deposition station; and a second depositing step for depositing an extended layer defined by extended crystalline columns over said crystalline columns of said seed layer through self-epitaxial growth at a second deposition stations, wherein; (a) the second deposition step is carried out by the use of a vacuum deposition technique, (b) the initial incident angle employed during the performance of the sputtering process referred to in the first deposition step, is smaller than 20° and, a shield is used to define the particular angle, (c) both of the seed layer and the extended layer are formed of the same ferromagnetic metal.
Claim 2
Independent Claim
142 words
A method for making magnetic recording media comprising the steps of: a first depositing step for depositing, through a sputtering process, a seed layer defined by crystalline columns of magnetic material densely and perpendicularly formed on a substrate at a first deposition station; and a second depositing step for depositing an extended layer defined by extended crystalline columns over said crystalline columns of said seed layer through self-epitaxial growth at a second deposition stations, wherein; (a) the second deposition step is carried out by the use of a vacuum deposition technique, (b) the initial incident angle employed during the performance of the sputtering process referred to in the first deposition step, is smaller than 20° and, a shield is used to define the particular angle, (c) both of the seed layer and the extended layer are formed of the same ferromagnetic metal.
Claim 3
Dependent Claim
20 words
A method as claimed in claim 1, wherein said seed layer is deposited with an initial incident angle of 5°.
Claim 4
Dependent Claim
27 words
A method as claimed in claim 1, wherein said extended layer is deposited with an initial incident angle greater than that arranged for depositing said seed layer.
Claim 5
Dependent Claim
19 words
A method as claimed in claim 1, wherein said seed layer has a thickness about 0.01 micrometer or greater.
Claim 6
Dependent Claim
23 words
A method as claimed in claim 1, wherein the combined thickness of said seed layer and said extended layer is about 0.3 micrometer.
Claim 7
Dependent Claim
16 words
A method as claimed in claim 1, wherein said substrate is made of a PET tape.
Claim 8
Dependent Claim
16 words
A method as claimed in claim 1, wherein said substrate is made of an polyamide tape.
Claim 9
Dependent Claim
16 words
A method as claimed in claim 1, wherein said substrate is made of an polyimide tape.
Claim 10
Dependent Claim
25 words
A method as claimed in claim 1, wherein said seed layer is deposited on said substrate which is heated to 100° C. to 120° C.
Claim 11
Dependent Claim
25 words
A method as claimed in claim 1, wherein said extended layer is deposited on said substrate which is heated to 40° C. to 70° C.
Claim 12
Dependent Claim
21 words
A method as claimed in claim 1, wherein said first depositing step is carried out by a targets facing sputtering system.
Claim 13
Dependent Claim
20 words
A method as claimed in claim 1, wherein said first depositing step is carried out by a magnetron sputtering system.
Claim 14
Dependent Claim
21 words
A method as claimed in claim 1, wherein said second depositing step is carried out by a targets facing sputtering system.
Claim 15
Dependent Claim
20 words
A method as claimed in claim 1, wherein said second depositing step is carried out by a magnetron sputtering system.
Claim 16
Dependent Claim
23 words
A method as claimed in claim 1, wherein said second depositing step is carried out by a dry deposition system other than sputtering.
Claim 17
Dependent Claim
21 words
A method as claimed in claim 1, wherein said second depositing step is carried out by an ion plating deposition system.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-08-30 | 1992-02-29 | 1992-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-30 | 1996-02-29 | 1996-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-30 | 2000-02-29 | 2000-08-30 | $7700.00 | Window Closed / Lapsed |