US4647494A
Expired / Lapsed
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Silicon/carbon protection of metallic magnetic structures
Assignee: HGST Netherlands BV
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Filing: 1985-10-31
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Granted: 1987-03-03
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Expires: 2005-10-31
Abstract
Abstract A superior wear-resistant coating is provided for metallic magnetic recording layers, where the improved coating is a hard carbon layer that is strongly bound to the underlying metallic magnetic recording layer by an intermediate layer of silicon. The silicon layer can be very thin, with a minimum thickness of a few atomic layers, and provides strong adhesion between the hard carbon protective layer and the metallic magnetic recording layer. A preferred technique for depositing both the intermediate silicon layer and the hard carbon layer is plasma deposition, since both of these depositions can be performed in the same reactor without breaking vacuum.
Inventors
- 👤 Bernard S. Meyerson
- 👤 Rajiv V. Joshi
- 👤 Robert Rosenberg
- 👤 Vishnubhai V. Patel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:49
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/72; G11B5/726; G11B5/7262; G11B5/7264; Y; Y10; Y10S; Y10S428/00; Y10S428/90; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/24975; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265; Y10T428/30
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
81 words
A magnetic recording medium, including: a substrate, a metallic magnetic recording layer on said substrate, said metallic layer being capable of storing information therein, a protective coating for said metallic magnetic layer including a first continuous layer comprised of silicon deposited on said metallic magnetic recording layer, said silicon layer being deposited to a thickness less than 500 angstroms, and a nongraphitic hard carbon layer deposited on said silicon layer, said carbon layer having a thickness of about 25 angstroms--1 micron.
Claim 2
Dependent Claim
81 words
A magnetic recording medium, including: a substrate, a metallic magnetic recording layer on said substrate, said metallic layer being capable of storing information therein, a protective coating for said metallic magnetic layer including a first continuous layer comprised of silicon deposited on said metallic magnetic recording layer, said silicon layer being deposited to a thickness less than 500 angstroms, and a nongraphitic hard carbon layer deposited on said silicon layer, said carbon layer having a thickness of about 25 angstroms--1 micron.
Claim 3
Dependent Claim
27 words
The recording medium of claim 1, wherein said first layer comprised of silicon is a continuous film having a thickness of at least a few atomic layers.
Claim 4
Dependent Claim
29 words
The recording medium of claim 1, where said first layer comprised of silicon is deposited as a substantially amorphous silicon layer having a thickness less than about 100 angstroms.
Claim 5
Dependent Claim
20 words
The recording medium of claim 3, where said hard carbon layer is deposited as a substantially amorphous layer of carbon.
Claim 6
Dependent Claim
17 words
The recording medium of claim 1, where said hard carbon layer is comprised of substantially amorphous carbon.
Claim 7
Dependent Claim
18 words
The recording medium of claim 1, where said metallic magnetic layer is an alloy including magnetic metallic elements.
Claim 8
Dependent Claim
16 words
The recording medium of claim 1, where said hard carbon layer has an atomicaly smooth surface.
Claim 9
Dependent Claim
23 words
The recording medium of claim 1, where said substrate is selected from the group consisting of Al, Si, ceramics, epoxies, glass, and polymers.
Claim 10
Dependent Claim
34 words
The recording medium of claim 1, where said first layer comprised of silicon forms silicides at the interface with said metallic magnetic layer and Si-C bonds at the interface with said hard carbon layer.
Claim 11
Dependent Claim
68 words
A magnetic recording medium, including: a metallic magnetic recording layer on said substrate, said metallic layer being capable of storing information therein, a protective coating for said metallic magnetic layer comprising amorphous continuous silicon plasma-deposited on said metallic magnetic layer to a thickness less than 500 angstroms and nongraphitic amorphous hard carbon plasma-deposited on said amorphous silicon, said hard carbon having a thickness less than about 1 micron.
Claim 12
Dependent Claim
68 words
A magnetic recording medium, including: a metallic magnetic recording layer on said substrate, said metallic layer being capable of storing information therein, a protective coating for said metallic magnetic layer comprising amorphous continuous silicon plasma-deposited on said metallic magnetic layer to a thickness less than 500 angstroms and nongraphitic amorphous hard carbon plasma-deposited on said amorphous silicon, said hard carbon having a thickness less than about 1 micron.
Claim 13
Dependent Claim
37 words
The recording medium of claim 10, where said amorphous silicon is plasma-deposited to a thickness of at least a few atomic layers and said amorphous carbon is plasma-deposited to a thickness of at least about 25 angstroms.
Claim 14
Dependent Claim
24 words
The recording medium of claim 10, where said substrate is selected from the group consisting of Al, Si, epoxies, ceramics, paper, glass, and polymers.
Claim 15
Dependent Claim
16 words
The recording medium of claim 10, where said amorphous hard carbon has an atomically smooth surface.
Claim 16
Dependent Claim
32 words
The recording medium of claim 10, where said amorphous silicon forms silicides at the interface with said metallic magnetic layer and forms Si-C bonds at the interface with said amorphous hard carbon.
Claim 17
Independent Claim
123 words
A method for producing a metallic magnetic recording medium comprising the steps of: depositing a metallic magnetic recording layer on a substrate, said metallic recording layer being capable of storing information therin, depositing a continuous layer of silicon to a depth less than about 100 angstroms on said metallic magnetic recording layer by plasma deposition in a reactor, said plasma deposition decomposing a gas including a gas source of silicon, and plasma depositing a layer of nongraphitic hard carbon to a thickness less than about one micron on said deposited silicon layer, said plasma deposition of carbon occurring in said reactor by the introduction of a gaseous species including carbon into said reactor while maintaining substantially the same vacuum level in said reactor.
Claim 18
Independent Claim
123 words
A method for producing a metallic magnetic recording medium comprising the steps of: depositing a metallic magnetic recording layer on a substrate, said metallic recording layer being capable of storing information therin, depositing a continuous layer of silicon to a depth less than about 100 angstroms on said metallic magnetic recording layer by plasma deposition in a reactor, said plasma deposition decomposing a gas including a gas source of silicon, and plasma depositing a layer of nongraphitic hard carbon to a thickness less than about one micron on said deposited silicon layer, said plasma deposition of carbon occurring in said reactor by the introduction of a gaseous species including carbon into said reactor while maintaining substantially the same vacuum level in said reactor.
Claim 19
Dependent Claim
40 words
The method of claim 15, where said silicon is deposited at amorphous silicon to a depth of at least a few atomic layers, and said carbon is deposited as amorphous carbon to a thickness of at least about 25 angstroms.
Claim 20
Dependent Claim
23 words
The method of claim 16, where said substrate is selected from the group consisting of Al, Si, epoxies, paper, glass, polymers, and ceramics.
Claim 21
Dependent Claim
36 words
The method of claim 16, where the plasma deposition of said amorphous carbon is at a temperature less than about 325° C., and said amorphous silicon is deposited at a temperature less than about 400° C.
Claim 22
Dependent Claim
17 words
The method of claim 16, where said amorphous silicon and amorphous carbon are deposited at room temperature.
References Cited (Backward Citations)
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