US4814259A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Laser generated electrically conductive pattern
Assignee: Boeing North American Inc
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Filing: 1987-11-09
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Granted: 1989-03-21
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Expires: 2007-11-09
Abstract
Abstract A conductive or semiconductive pattern of a metal sulfide or selenide such as copper, cadmium, cobalt or nickel sulfide, is provided on a substrate. The pattern may have a resistivity in the range of 1 to 106 ohms per square. It is formed by coating the surface with a solution containing a salt of one of the metals which is capable of being converted to a divalent metal compound, a sulfur group donor such as thiourea, and a solvent such as methanol or water. The solution is dried, and then selected portions of the coated surface are irradiated with a laser beam. This thermally converts the irradiated metal salt into a metal sulfide. The unreacted solution is then washed from the substrate to leave a conductive pattern. The desired conductivity of the pattern can be obtained by selecting the proper metal salt, concentration of salt in the solution, and the energy of the radiation.
Inventors
- 👤 Paul R. Newman
- 👤 Leslie F. Warren, Jr.
- 👤 Patricia H. Cunningham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:22
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C04B41/45; C04B41/4505; C04B41/455; C04B41/50; C04B41/5007; C04B41/5014; C04B41/80; C04B41/81; C04B41/85; G; G03; G03F; G03F7/00; G03F7/004; G03F7/0042; G03F7/0043; H; H01; H01B; H01B1/00; H01B1/06; H01B1/10; H05; H05K; H05K3/00; H05K3/10; H05K3/105; H10; H10P; H10P14/00; H10P14/40; H10P14/412; C04B2111/00; C04B2111/00474; C04B2111/00844; C04B2111/90; C04B2111/94; H05K2203/00; H05K2203/10; H05K2203/107; H05K2203/12; H05K2203/125; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
76 words
A method of producing an electrically conductive or semiconductive pattern on a substrate, which comprises: providing a substrate; providing a solution containing a soluble nickel salt capable of being converted to nickel sulfide, a sulfur donor, and a solvent; coating the surface of the substrate with the solution; evaporating solvent from the coated surface of the substrate; irradiating selected portions of the coated surface to form an electrically conductive pattern of nickel sulfide on the substrate.
Claim 2
Independent Claim
76 words
A method of producing an electrically conductive or semiconductive pattern on a substrate, which comprises: providing a substrate; providing a solution containing a soluble nickel salt capable of being converted to nickel sulfide, a sulfur donor, and a solvent; coating the surface of the substrate with the solution; evaporating solvent from the coated surface of the substrate; irradiating selected portions of the coated surface to form an electrically conductive pattern of nickel sulfide on the substrate.
Claim 3
Dependent Claim
35 words
The method as claimed in claim 1 wherein the substrate is a material selected from the group consisting of ceramic, metal, plastic, semiconductor, fiberglass, fiberglass reinforced Kapton, Kapton, Bakelite, alumina, and board for printed circuits.
Claim 4
Dependent Claim
12 words
The method as claimed in claim 1 wherein the solvent is water.
Claim 5
Dependent Claim
12 words
The method as claimed in claim 1 wherein the solvent is methanol.
Claim 6
Dependent Claim
33 words
The method as claimed in claim 1 wherein the soluble nickel salt is selected from the group consisting of nickel acetate tetrahydrate, nickel acetate, nickel sulfate, nickel chloride, nickel nitrate, and nickel tetrafluoroborate.
Claim 7
Dependent Claim
31 words
The method as claimed in claim 1 wherein the sulfur donor is selected from the group consisting of thiourea, alkali metal thiosulfates, ammonium thiosulfates, alkali metal thiophosphates, ammonium thiophosphates, and thioacetamide.
Claim 8
Dependent Claim
33 words
The method as claimed in claim 1 wherein the nickel salt concentration ranges from about 0.05 to about 2 molar, and the sulfur donor concentration ranges from about 0.05 to about 2 molar.
Claim 9
Dependent Claim
21 words
The method as claimed in claim 1 wherein the irradiating of selected portions comprises irradiating selected portions with a laser beam.
Claim 10
Dependent Claim
26 words
The method as claimed in claim 8 wherein the laser beam is a CO 2 laser having a power density of about 40 W/cm 2 .
Claim 11
Dependent Claim
31 words
The method as claimed in claim 8 wherein the fluence of the laser radiation is in the range of about 1 W sec/cm 2 to about 25 W sec/cm 2 .
Claim 12
Dependent Claim
29 words
The method as claimed in claim 8 wherein the fluence of the laser radiation is selected to obtain a desired conductivity in the irradiated portions of the coated substrate.
Claim 13
Dependent Claim
18 words
The method as claimed in claim 1 including washing the substrate to remove unreacted reagents from the surface.
Claim 14
Dependent Claim
20 words
The method as claimed in claim 1 wherein the substrate is etched prior to coating its surface with the solution.
Claim 15
Independent Claim
102 words
A method of producing an electrically conductive pattern on a substrate, comprising: providing a substrate; providing a solution containing a soluble metal salt which is capable of being converted to a divalent metal compound selected from the group consisting of soluble salts of copper, cadmium, cobalt, and nickel, a donor selected from the sulfur group consisting of sulfur and selenium and a solvent; coating the surface of the substrate with the solution; evaporating solvent from the coated surface of the substrate; irradiating selected portions of the coated surface to form an electrically conductive pattern of the divalent metal compound on the substrate.
Claim 16
Independent Claim
102 words
A method of producing an electrically conductive pattern on a substrate, comprising: providing a substrate; providing a solution containing a soluble metal salt which is capable of being converted to a divalent metal compound selected from the group consisting of soluble salts of copper, cadmium, cobalt, and nickel, a donor selected from the sulfur group consisting of sulfur and selenium and a solvent; coating the surface of the substrate with the solution; evaporating solvent from the coated surface of the substrate; irradiating selected portions of the coated surface to form an electrically conductive pattern of the divalent metal compound on the substrate.
Claim 17
Independent Claim
82 words
A method of generating an electrically conductive pattern on a substrate comprising the steps of: providing a substrate; providing a solution of nickel acetate, thiourea, and a solvent; coating the surface of the substrate with the solution; evaporating solvent to leave a film of the nickel acetate and thiourea on the surface; irradiating selected areas of the surface with a laser beam to form an electrically conducting pattern of nickel sulfide; and washing the surface to remove unreacted portions of the film.
Claim 18
Independent Claim
82 words
A method of generating an electrically conductive pattern on a substrate comprising the steps of: providing a substrate; providing a solution of nickel acetate, thiourea, and a solvent; coating the surface of the substrate with the solution; evaporating solvent to leave a film of the nickel acetate and thiourea on the surface; irradiating selected areas of the surface with a laser beam to form an electrically conducting pattern of nickel sulfide; and washing the surface to remove unreacted portions of the film.
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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) | 1992-03-20 | 1992-09-19 | 1993-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-20 | 1996-09-19 | 1997-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-20 | 2000-09-19 | 2001-03-21 | $7700.00 | Window Closed / Lapsed |