Claims
- 1. A process for the manufacture of an electrode on a heat-resisting and isolating substrate which comprises
- applying on the substrate a paste comprising 5 to 30 weight percent of a metal material and an organic vehicle, said metal material containing 5 to 60 weight percent of a silver component and 95 to 40 weight percent of a base metal component containing at least one member selected from the group consisting of nickel, copper, aluminum, zinc, tin iron and cobalt,
- heating the substrate containing the applied paste at a temperature of 350.degree. to 600.degree. C. to form on the substrate a metallic particle layer of 0.2 to 1 micron in thickness, where the organic vehicle in the paste is consumed, and
- subsequently building up on the metallic particle layer by electroless plating an electrode of nickel or copper having a thickness of 0.5 to 20 microns,
- whereby the base metal component improves the adhesive force and the electrical characteristics including dielectric constant and the tan .delta. of the electrode, and whereby the base metal component prevents the migration of the silver component thereby to improve the useful life of the electrode under humid conditions.
- 2. A process according to claim 1, wherein said heat-resisting and isolating substrate is a ceramic substrate.
- 3. A process according to claim 1, wherein said substrate is roughened by chemical and mechanical treatment prior to application of the paste.
- 4. A process according to claim 1, wherein said base metal component is nickel.
- 5. A process according to claim 1, wherein said metal material component contains a palladium component of 0.01 to 5 weight %.
- 6. A process according to claim 1, wherein said silver component is silver powder under 2 microns in diameter and a silver compound which is reduced to silver metal by heat-treatment, and said base metal component is a powder of metal and alloy under 2 microns in diameter.
- 7. A process according to claim 1, wherein the paste contains 0.5 to 5 weight % of glass powder and low-melting oxide.
- 8. A process according to claim 7, wherein said glass powder comprises B.sub.2 O.sub.3 and said oxide is B.sub.2 O.sub.3.
- 9. A process according to claim 1, wherein the paste contains carbon powder and inorganic powder in an amount of 1 to 30 weight percent.
- 10. A process according to claim 1, wherein said metallic particle layer formed by heat-treatment is 0.2 to 1 microns in average thickness.
- 11. A process according to claim 1, wherein the electrode formed by electroless plating is 1 to 10 microns in thickness.
- 12. A process according to claim 1, wherein the heat-treated substrate is treated in Pt ion, Os ion, Ir ion, Ru ion before electroless plating.
- 13. A process according to claim 1, wherein the heat-treated substrate is immersed in a solution comprising at least one member of the group consisting of an organic acid, ammonia solution, nitric acid and sulfuric acid.
Parent Case Info
This application is a continuation, of now abandoned application Ser. No. 293,981, field 8/18/81.
US Referenced Citations (5)
Foreign Referenced Citations (1)
Number |
Date |
Country |
52-53732 |
Apr 1977 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
293981 |
Aug 1981 |
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