US5169676A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control of crystallite size in diamond film chemical vapor deposition
Assignee: United States Department of the Navy
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Filing: 1991-05-16
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Granted: 1992-12-08
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Expires: 2011-05-16
Abstract
Abstract In depositing an adhering, continuous, polycrystalline diamond film of optical or semiconductor quality on a substrate, as by forming on the substrate a layer of a refractory nitride interlayer and depositing diamond on the interlayer without mechanical treatment or seeding of the substrate or the interlayer, the substrate is heated in a vacuum chamber containing a microwave activated mixture of hydrogen and a gas including carbon, and the size of deposited diamond crystallites and their rate of deposition selectively varied by a bias voltage applied to the substrate.
Inventors
- 👤 Mark B. Moran
- 👤 Linda F. Johnson
- 👤 Karl A. Klemm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:20
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/26; C23C16/27; C23C16/274; C23C16/277; C23C16/44; C23C16/50; C23C16/511; C23C16/52; C30; C30B; C30B25/00; C30B25/02; C30B25/10; C30B25/105; C30B29/00; C30B29/02; C30B29/04; Y; Y10; Y10T; Y10T428/00; Y10T428/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
73 words
A method of forming diamond crystallites, the method comprising: providing a substrate having a surface of refractory nitride material; depositing said diamond directly on said surface by chemical vapor deposition from an activated gaseous mixture within reaction chamber walls electrically insulated from said substrate, said mixture including hydrogen and a gas containing carbon; and providing said substrate with an electrical bias voltage relative to said walls for controlling the size of said crystallites.
Claim 2
Independent Claim
73 words
A method of forming diamond crystallites, the method comprising: providing a substrate having a surface of refractory nitride material; depositing said diamond directly on said surface by chemical vapor deposition from an activated gaseous mixture within reaction chamber walls electrically insulated from said substrate, said mixture including hydrogen and a gas containing carbon; and providing said substrate with an electrical bias voltage relative to said walls for controlling the size of said crystallites.
Claim 3
Dependent Claim
30 words
The method of claim 1 wherein said bias voltage of said substrate relative to said walls is in a range of about 25 volts positive to about 80 volts negative.
Claim 4
Dependent Claim
40 words
The method of claim 2 wherein said bias voltage is made relatively more positive within said range to decrease the size of said crystallites and is made relatively more negative within said range to increase the size of said crystallites.
Claim 5
Dependent Claim
34 words
The method of claim 1 wherein said bias voltage is made relatively more positive to decrease the size of said crystallites and is made relatively more negative to increase the size of said crystallites.
Claim 6
Dependent Claim
54 words
The method of claim 1 wherein said refractory nitride material has a thickness of at least 500 angstrom units; said mixture is activated by microwave energy; said substrate is at a temperature in the range of about 550 to about 1100 degrees centigrade; and the pressure of said mixture is below about 100 Torr.
Claim 7
Dependent Claim
23 words
The method of claim 5 wherein said bias voltage is in a range of about 25 volts positive to about 80 volts negative.
Claim 8
Dependent Claim
56 words
In a chemical vapor deposition method for depositing a film of diamond crystallites on a substrate disposed within a reaction chamber walls together with an activated gas providing carbon from which said crystallites are formed, an improvement for controlling the size of said crystallites comprises providing a bias voltage of said substrate relative to said walls.
Claim 9
Dependent Claim
56 words
In a chemical vapor deposition method for depositing a film of diamond crystallites on a substrate disposed within a reaction chamber walls together with an activated gas providing carbon from which said crystallites are formed, an improvement for controlling the size of said crystallites comprises providing a bias voltage of said substrate relative to said walls.
Claim 10
Dependent Claim
40 words
The improvement of claim 7 further comprising said bias voltage of said substrate relative to said walls being relatively more positive to decrease the size of said crystallites and being relatively more negative to increase the size of said crystallites.
Claim 11
Dependent Claim
57 words
In a chemical vapor deposition method for depositing a film of diamond crystallites on a substrate disposed within walls of a reaction chamber together with an activated gas providing carbon from which said crystallites are formed, an improvement for controlling the size of said crystallites comprising providing a bias voltage of said substrate relative to said walls.
Claim 12
Dependent Claim
57 words
In a chemical vapor deposition method for depositing a film of diamond crystallites on a substrate disposed within walls of a reaction chamber together with an activated gas providing carbon from which said crystallites are formed, an improvement for controlling the size of said crystallites comprising providing a bias voltage of said substrate relative to said walls.
Claim 13
Dependent Claim
31 words
The improvement of claim 7 further comprising said bias voltage of said substrate relative to said walls being in a range of about 25 volts positive to about 80 volts negative.
Claim 14
Dependent Claim
46 words
The improvement of claim 10 further comprising said bias voltage of said substrate relative to said walls being relatively more positive within said range of decrease the size of said crystallites and being relatively more negative within said range to increase the size of said crystallites.
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) | 1995-12-08 | 1996-06-08 | 1996-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-08 | 2000-06-08 | 2000-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-08 | 2004-06-08 | 2004-12-08 | $7700.00 | Window Closed / Lapsed |