Patent US3582611A successfully refreshed from Google Patents.
US3582611A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method of metal evaporation including an evaporation boat having lower electrical resistivity ends than the center thereof
Assignee: GTE Sylvania Inc
•
Filing: 1969-11-24
•
Granted: 1971-06-01
•
Expires: 1989-11-24
Abstract
Abstract In an apparatus for evaporation and vacuum deposition of metal on an article to be coated therewith, spaced-apart electrical binding posts are located within a vacuum chamber. The ends of an electrical self-resistance-heated evaporation boat are clamped to the binding posts. The end portions of the boat have a lower electrical resistivity than the center portion in order to minimize contact resistance and to reduce power dissipation at the ends of the boats.
Inventors
- 👤 Wilfrid G Matheson
- 👤 Edmund M Passmore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:17
CPC Classifications
C; C23; C23C; C23C14/00; C23C14/22; C23C14/24; C23C14/26
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
76 words
An elongated boat for the evaporation of metal comprising a monolithic structure having a cavity at about its center and having ends suitable for attachment to the binding posts of evaporation apparatus, said structure comprising at least two electrically conductive blends of refractory powders, the resistivity of one blend being lower than the other and wherein said lower resistivity blend constitutes the ends of said boat and the other blend constitutes the center of said boat.
Claim 2
Dependent Claim
76 words
An elongated boat for the evaporation of metal comprising a monolithic structure having a cavity at about its center and having ends suitable for attachment to the binding posts of evaporation apparatus, said structure comprising at least two electrically conductive blends of refractory powders, the resistivity of one blend being lower than the other and wherein said lower resistivity blend constitutes the ends of said boat and the other blend constitutes the center of said boat.
Claim 3
Dependent Claim
21 words
The apparatus of claim 1 wherein said boat comprises a dense monolithic structure of at least two blends of refractory powders.
Claim 4
Dependent Claim
52 words
The apparatus of claim 2 wherein the ends of said boat comprise a blend including titanium diboride and boron nitride and have a resistivity less than 1,000 microhm-centimeters and the center of said boat comprises a blend including titanium diboride and boron nitride and has a resistivity greater than 1, 000 microhm-centimeters.
Claim 5
Independent Claim
93 words
A method of evaporating metal including the steps of: disposing a roll of wire of said metal in a vacuum chamber; sealing said chamber and reducing the pressure therein; unwinding said roll and directing the free end of said wire into the cavity of a unitary variable-resistance evaporation boat, said boat having low resistivity ends and a higher resistivity center, the ends of said boat being clamped to electrical binding posts within said chamber; and passing sufficient electrical current through said boat to heat it to the evaporation temperature of said metal wire.
Claim 6
Independent Claim
93 words
A method of evaporating metal including the steps of: disposing a roll of wire of said metal in a vacuum chamber; sealing said chamber and reducing the pressure therein; unwinding said roll and directing the free end of said wire into the cavity of a unitary variable-resistance evaporation boat, said boat having low resistivity ends and a higher resistivity center, the ends of said boat being clamped to electrical binding posts within said chamber; and passing sufficient electrical current through said boat to heat it to the evaporation temperature of said metal wire.
Claim 7
Dependent Claim
28 words
The method of claim 4 wherein said metal is aluminum and said boat comprises at least two blends of refractory metal powders including titanium diboride and boron nitride.
Claim 8
Dependent Claim
16 words
The boat of claim 1 wherein both of said blends comprise boron nitride and titanium diboride.
Claim 9
Dependent Claim
20 words
The boat of claim 1 wherein the resistivity of the ends of said boat is less than about 1,000 microhm-centimeters.
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) | 1974-05-31 | 1974-11-30 | 1975-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-31 | 1978-11-30 | 1979-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-31 | 1982-11-30 | 1983-06-01 | $7700.00 | Window Closed / Lapsed |