US4400410A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating insulating materials by glow discharge
Assignee: BTG International Ltd
•
Filing: 1981-08-14
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Granted: 1983-08-23
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Expires: 2001-08-14
Abstract
Abstract Coatings of hard carbon, silicon, or germanium are applied to electrically insulating materials in a D.C. glow discharge chamber. Initiation and maintenance of a glow discharge is ensured by using a cathode of larger area than the material to be coated. For example the cathode may be twice the diameter of the material to be coated. Materials capable of being coated include zinc sulphide, zinc selenide, silica, and glass. The gases used are hydrocarbon e.g. butane, methane, etc. for carbon coatings; silane for silicon coatings; and germane for germanium coatings.
Inventors
- 👤 Geoffrey W. Green
- 👤 Alan H. Lettington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:22
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/44; C23C16/50; C23C16/503
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
56 words
A method of depositing coatings on an electrically insulating material substrate in a glow discharge chamber supplied with D.C. electrical power wherein the substrate is mounted on an electrically conducting cathode of larger area than the substrate whereby the exposed area of the cathode serves to maintain a glow discharge and dark space above the substrate.
Claim 2
Independent Claim
56 words
A method of depositing coatings on an electrically insulating material substrate in a glow discharge chamber supplied with D.C. electrical power wherein the substrate is mounted on an electrically conducting cathode of larger area than the substrate whereby the exposed area of the cathode serves to maintain a glow discharge and dark space above the substrate.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein the coating is infra red transparent hard carbon deposited from a hydrocarbon gas.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein the coating is silicon deposited from silane gas.
Claim 5
Dependent Claim
14 words
The method of claim 1 wherein the coating is germanium deposited from germane gas.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein the substrate is heated prior to depositing the coating.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein the substrate is cleaned by ion bombardment prior to depositing the coating.
Claim 8
Dependent Claim
18 words
The method of claim 1 wherein at least two layers of different materials are deposited on the substrate.
Claim 9
Independent Claim
109 words
An apparatus for depositing a coating on an electrically insulating substrate, comprising: a vacuum chamber; an anode structure within said vacuum chamber; means for providing a vacuum condition in said chamber; means for supplying a gas into said chamber; a cathode structure, within said chamber, having a recessed surface for carrying said substrate to be coated, said cathode structure having a substantially larger area than said substrate so that exposed areas of said cathode structure maintain a glow discharge and a dark space above said substrate while D.C. power is applied to said anode and cathode structures; and means for supplying D.C. power to said anode and cathode structures.
Claim 10
Independent Claim
109 words
An apparatus for depositing a coating on an electrically insulating substrate, comprising: a vacuum chamber; an anode structure within said vacuum chamber; means for providing a vacuum condition in said chamber; means for supplying a gas into said chamber; a cathode structure, within said chamber, having a recessed surface for carrying said substrate to be coated, said cathode structure having a substantially larger area than said substrate so that exposed areas of said cathode structure maintain a glow discharge and a dark space above said substrate while D.C. power is applied to said anode and cathode structures; and means for supplying D.C. power to said anode and cathode structures.
Claim 11
Dependent Claim
16 words
Apparatus as claimed in claim 8 wherein the cathode structure includes means for controlling its temperature.
Claim 12
Independent Claim
119 words
An apparatus for depositing a coating on an electrically insulating substrate, comprising: a vacuum chamber; an anode structure within said vacuum chamber; means for providing a vacuum condition in said chamber; means for supplying a gas into said chamber; a cathode structure, within said chamber, for carrying said substrate to be coated, the cathode structure having a substantially larger area than that of said substrate so that exposed areas of said cathode structure maintain a glow discharge and a dark space above said substrate while D.C. power is applied to said anode and cathode structures; a grounded shield surrounding said cathode structure for confining the glow discharge; and means for supplying D.C. power to said anode and cathode structures.
Claim 13
Independent Claim
119 words
An apparatus for depositing a coating on an electrically insulating substrate, comprising: a vacuum chamber; an anode structure within said vacuum chamber; means for providing a vacuum condition in said chamber; means for supplying a gas into said chamber; a cathode structure, within said chamber, for carrying said substrate to be coated, the cathode structure having a substantially larger area than that of said substrate so that exposed areas of said cathode structure maintain a glow discharge and a dark space above said substrate while D.C. power is applied to said anode and cathode structures; a grounded shield surrounding said cathode structure for confining the glow discharge; and means for supplying D.C. power to said anode and cathode structures.
Claim 14
Dependent Claim
16 words
An apparatus according to claim 10 wherein said cathode structure comprises means for controlling its temperature.
Claim 15
Dependent Claim
71 words
A substrate having a surface coated with a first thin bonding layer of silicon and a second layer of infra red transparent hard carbon formed by the following method steps; mounting the substrate on an electrically insulating cathode of larger area than the substrate; and applying D.C. power to produce a glow discharge, the exposed area of the cathode serving to maintain glow discharge and a dark space above the substrate.
Claim 16
Dependent Claim
71 words
A substrate having a surface coated with a first thin bonding layer of silicon and a second layer of infra red transparent hard carbon formed by the following method steps; mounting the substrate on an electrically insulating cathode of larger area than the substrate; and applying D.C. power to produce a glow discharge, the exposed area of the cathode serving to maintain glow discharge and a dark space above the substrate.
Claim 17
Dependent Claim
14 words
A substrate as claimed in claim 12 wherein the substrate material is zinc sulphide.
Claim 18
Dependent Claim
14 words
A substrate as claimed in claim 12 wherein the substrate material is zinc selenide.
Claim 19
Dependent Claim
262 words
A coated substrate formed in a glow discharge chamber in accordance with the following fabrication steps: providing an electrically conducting cathode within a chamber of larger area than that of the substrate; mounting the substrate onto the cathode thereby covering a portion of the cathode and leaving a portion of the cathode exposed; substantially evaculating any air from within the chamber; admitting into the chamber a gas containing silicon molecules; applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during the glow discharge reducing any positive charge accumulation at the substrate, thereby forming a thin bonding layer of silicon on the substrate; removing the gas containing silicon molecules from the chamber; admitting a hydrocarbon gas into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during the glow discharge reducing any positive charge accumulation at the substrate, thereby forming a thin bonding layer of silicon on the substrate; removing the gas containing silicon molecules from the chamber; admitting a hydrocarbon gas into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during glow discharge reducing any positive charge accumulation at the substrate, thereby forming a coating on the substrate of infra red transparent hard carbon.
Claim 20
Dependent Claim
262 words
A coated substrate formed in a glow discharge chamber in accordance with the following fabrication steps: providing an electrically conducting cathode within a chamber of larger area than that of the substrate; mounting the substrate onto the cathode thereby covering a portion of the cathode and leaving a portion of the cathode exposed; substantially evaculating any air from within the chamber; admitting into the chamber a gas containing silicon molecules; applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during the glow discharge reducing any positive charge accumulation at the substrate, thereby forming a thin bonding layer of silicon on the substrate; removing the gas containing silicon molecules from the chamber; admitting a hydrocarbon gas into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during the glow discharge reducing any positive charge accumulation at the substrate, thereby forming a thin bonding layer of silicon on the substrate; removing the gas containing silicon molecules from the chamber; admitting a hydrocarbon gas into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during glow discharge reducing any positive charge accumulation at the substrate, thereby forming a coating on the substrate of infra red transparent hard carbon.
Claim 21
Dependent Claim
17 words
A substrate formed according to the fabrication steps of claim 15 wherein the substrate comprises zinc sulphide.
Claim 22
Dependent Claim
17 words
A substrate formed according to the fabrication steps of claim 15 wherein the substrate comprises zinc selenide.
Claim 23
Independent Claim
130 words
A method of depositing a coating on an electrically insulating material substrate in a glow discharge chamber comprising the steps of; providing an electrically conducting cathode, within the chamber, of larger area than that of the substrate; mounting the substrate onto the cathode thereby covering a portion of the cathode and leaving a portion of the cathode exposed; substantially evacuating any air from within the chamber; admitting a gas containing molecules of a coating material into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during glow discharge reducing any positive charge accumulation at the substrate, thereby forming a coating on the substrate.
Claim 24
Independent Claim
130 words
A method of depositing a coating on an electrically insulating material substrate in a glow discharge chamber comprising the steps of; providing an electrically conducting cathode, within the chamber, of larger area than that of the substrate; mounting the substrate onto the cathode thereby covering a portion of the cathode and leaving a portion of the cathode exposed; substantially evacuating any air from within the chamber; admitting a gas containing molecules of a coating material into the chamber; maintaining the temperature of the substrate to less than 300° C.; and applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, the flow of electrons during glow discharge reducing any positive charge accumulation at the substrate, thereby forming a coating on the substrate.
Claim 25
Dependent Claim
30 words
A method according to claim 18 wherein said step of admitting a gas comprises the step of admitting a hydrocarbon gas, the coating deposited being an infrared transparent hard carbon.
Claim 26
Dependent Claim
27 words
A method according to claim 18 wherein said step of admitting a gas comprises the step of admitting a silane gas, the coating deposited being a silicon.
Claim 27
Dependent Claim
26 words
A method according to claim 18 wherein said step of admitting a gas comprises the step of admitting a germane gas, the coating deposited being germanium.
Claim 28
Dependent Claim
19 words
A method according to claim 18 further including, before the step of maintaining, the step of heating the substrate.
Claim 29
Dependent Claim
25 words
A method according to claim 18 further including the step of cleaning the substrate by ion bombardment prior to applying the coating by glow discharge.
Claim 30
Dependent Claim
46 words
A method according to claim 23 wherein said cleaning step comprises the steps of: after substantially evacuating air from the chamber, introducing Argon gas into the chamber; and applying a D.C. voltage to the cathode causing initiation of a glow discharge at the exposed portion thereof.
Claim 31
Dependent Claim
68 words
A method according to claim 18 further including the steps of: evacuating the first gas from the chamber; introducing a second gas into the chamber containing molecules of a second coating material layer to be applied to the substrate; applying a D.C. voltage to the cathode causing a glow discharge at the exposed portion of the cathode, thereby forming a coating of the second material on the substrate.
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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) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |