US5215788A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combustion flame method for forming diamond films
Assignee: Toyota Central R&D Labs Inc
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Filing: 1991-06-21
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Granted: 1993-06-01
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Expires: 2011-06-21
Abstract
Abstract When a mixture of gases containing carbon is burned to form a film of diamond on a surface of a substrate held at an appropriate temperature, it is so burned as to form a substantially flat region of incomplete combustion lying in parallel to the substrate surface and contacting it, while the region is surrounded by an air-shielding gas stream or formed under a reduced pressure.
Inventors
- 👤 Motohide Murayam
- 👤 Shinji Kojima
- 👤 Katsuyuki Ohsawa
- 👤 Shoji Noda
- 👤 Kiyoshi Uchida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:45
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/26; C23C16/27; C23C16/275; C23C16/44; C23C16/453
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
110 words
A method of forming a film of diamond on a surface of a substrate comprising: (a) forming a region of incomplete combustion contacting the surface of the substrate by burning a mixture of gases containing carbon, the region having a flame temperature of at least about 3000° K; (b) creating a stagnant flow ahead of said substrate, the flow having a reduced velocity as the mixture approaches the substrate; (c) stabilizing said region of incomplete combustion in the stagnant flow to be in a substantially flat shape relative to the surface of said substrate; and (d) maintaining the substrate at a sufficient temperature to form the film of diamond thereon.
Claim 2
Independent Claim
110 words
A method of forming a film of diamond on a surface of a substrate comprising: (a) forming a region of incomplete combustion contacting the surface of the substrate by burning a mixture of gases containing carbon, the region having a flame temperature of at least about 3000° K; (b) creating a stagnant flow ahead of said substrate, the flow having a reduced velocity as the mixture approaches the substrate; (c) stabilizing said region of incomplete combustion in the stagnant flow to be in a substantially flat shape relative to the surface of said substrate; and (d) maintaining the substrate at a sufficient temperature to form the film of diamond thereon.
Claim 3
Dependent Claim
64 words
A method as set forth in claim 1, wherein stabilizing said region is performed by the following steps; (a) homogenizing a flow velocity of said mixture across a plane perpendicular to said flow of said mixture; and (b) balancing the component of said uniform flow velocity in a direction perpendicular to said region and the burning velocity of said mixture upstream of said region.
Claim 4
Dependent Claim
27 words
A method as set forth in claim 2, wherein stabilizing said region is further performed by surrounding said flow of said mixture with an air-shielding gas stream.
Claim 5
Dependent Claim
23 words
A method as set forth in claim 2, wherein said flow velocity is homogenized by contracting and rectifying said flow of said mixture.
Claim 6
Dependent Claim
23 words
A method as set forth in claim 2, wherein said region is stabilizing by placing said stagnant flow in a reduced pressure atmosphere.
Claim 7
Dependent Claim
17 words
A method as set forth in claim 3, wherein said air-shielding gas stream comprises a combustible gas.
Claim 8
Dependent Claim
17 words
A method as set forth in claim 3, wherein said air-shielding gas stream comprises an inert gas.
Claim 9
Dependent Claim
25 words
A method as set forth in claim 3, wherein said mixture contains an additive which lowers the burning velocity of said mixture in said region.
Claim 10
Dependent Claim
24 words
A method as set forth in claim 8, wherein said mixture has a carbon and oxygen atom ratio by mole of 1.0 to 1.1.
Claim 11
Dependent Claim
22 words
A method as set forth in claim 8, wherein said mixture is of acetylene and oxygen and contains hydrogen as said additive.
Claim 12
Dependent Claim
23 words
A method as set forth in claim 8, wherein said mixture is of acetylene and oxygen and contains a hydrocarbon as said additive.
Claim 13
Dependent Claim
24 words
A method as set forth in claim 8, wherein said mixture is of acetylene and oxygen and contains a saturated hydrocarbon as said additive.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-31 | 1996-11-30 | 1997-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-31 | 2000-11-30 | 2001-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-31 | 2004-11-30 | 2005-06-01 | $7700.00 | Window Closed / Lapsed |