Abstract: Adherent traces of a carbide-forming conductive metal are produced on a diamond surface, without deposition of carbide in areas to be non-conductive, by depositing an undercoat layer of a non-carbide-forming metal such as palladium, patterning said undercoat layer and then depositing a bond layer of the carbide-forming metal. The undercoat layer and the portion of the bond layer deposited thereon are then removed, typically by etching.

Abstract: A process for making metallized vias in diamond substrates is disclosed. The process involves laser-drilling a plurality of holes in a CVD diamond substrate and depositing tungsten, or a similar refractory metal, in the holes by low pressure CVD to provide substantially void-free metallized vias. Diamond substrates having metallized vias are also disclosed. The structures are useful for making multichip modules for high clock rate computers.

Abstract: Differences in thermal expansion properties between integrated circuit chips, especially of gallium arsenide, and the dielectric substrates (especially diamond and aluminum nitride) on which said chips are mounted are accommodated by interposing between the substrate and the chip a base having diamond pedestals in combination with a material of higher coefficient of thermal expansion than the substrate, typically a metal such as copper or tungsten. The base may be integral with a diamond substrate or may be a shim interposed between the substrate and the chip.

Abstract: It has been found that the prior activation of a palladium substrate, such as palladium electrolessly deposited onto nickel, in an aqueous solution of an alkali metal hydroxide, an alkali metal carbonate and a reducing agent, for example, dimethylamine borane, can provide an enhancement in the thickness and uniformity of electrolessly deposited gold when the activated substrate is placed in an electroless gold bath.

Abstract: An adherent layer comprising elemental titanium, optionally in combination with another metal such as copper, is deposited on a substrate, preferably of alumina or aluminum nitride, and serves as a base for a further conductive coating which may be applied by electroless or electrolytic deposition. The adherent layer is applied by contacting the substrate with a mixture of the elemental metal(s) and a substantially anhydrous salt composition, preferably an equimolar mixture of potassium chloride and sodium chloride; heating at a temperature and for a time sufficient to melt said salt composition; and removing said salt composition, preferably by water washing.

Abstract: Nickel or cobalt diffusion is suppressed in ceramic articles having a nickel or cobalt underlayer followed by a gold overlayer, by heat-treating the article in a reducing atmosphere at a temperature of at least about 650.degree. C. and subsequently depositing a final gold layer. By suppressing the diffusion of nickel or cobalt, the adhesion of hermetic lids attached thereto by soldering is improved.

Abstract: A method of improving adhesion of a nickel alloy to the surfaces of diamond particles and articles made therefrom. Diamond particles are electrolessly nickel plating with the nickel alloy formed with a transitional metal, such as molybdenum. Electrolessly plated particles are then gradually heated at a steady rate from room temperature to a desired heat treatment temperature in a non-oxidizing atmosphere formed by argon containing 10% hydrogen. Exemplary articles made by the aforementioned process include a grinding wheel having uniformly dispersed abrasive diamond particles having the Ni/Mo alloy coat thereon.

Abstract: Nickel or cobalt diffusion is suppressed in ceramic articles having a nickel or cobalt underlayer followed by a gold overlayer, by heat-treating the article in a reducing atmosphere at a temperature of at least about 650.degree. C. and subsequently depositing a final gold layer. By suppressing the diffusion of nickel or cobalt, the adhesion of hermetic lids attached thereto by soldering is improved.

Abstract: An aqueous autocatalytic electroless gold plating composition having improved stability, a high plating rate, and excellent throwing power is provided which comprises about 0.002 to about 0.05 moles per liter (M) of a water-soluble alkali metal monovalent gold cyanide complex, about 0.01 to about 0.1M of a water-soluble cyanide compound, about 0.1 to about 1.0M of a carbonate compound, about 0.1 to about 0.45M of an aliphatic amine, and about 0.01 to about 0.1M of a reducing agent selected from the group consisting of water soluble alkali metal borohydrides and water soluble amine boranes, the plating composition to having a pH in the range of about 10-14.

Abstract: An aqueous autocatalytic electroless gold plating composition having improved stability and which can plate gold directly onto gold or on nickel at an excellent rate is provided, the composition having a pH within the range of about 10 to about 14 and comprising about 0.002 to about 0.02M of a water-soluble alkali metal monovalent gold cyanide complex, about 0.01 to about 0.1M of a water-soluble alkali metal cyanide, about 0.1 to about 1.0M of a carbonate compound, about 0.01 to about 0.1M of a first reducing agent selected from the group consisting of water soluble alkali metal borohydrides and water soluble amine boranes, and about 0.01 to about 1.0M of a second reducing agent selected from the group consisting of hydrazine and hydrazine derivatives.

Abstract: An aqueous autocatalytic electroless gold plating composition having improved stability and an excellent plating rate is provided which comprises about 0.002 to about 005M of a water-soluble alkali metal monovalent gold cyanide complex, about 0.01 to about 0.1M of a water-soluble cyanide compound, about 0.1 to about 1.0M of a carbonte compound, and about 0.01 to about 0.1M of a reducing agent selected from the group consisting of water soluble alkali metal borohydrides and water soluble amine boranes, the plating composition having a plating rate within the range of about 10 to about 14.

Abstract: An aqueous electroless gold plating composition is disclosed comprising a water-soluble alkali metal monovalent gold cyanide complex, a water-soluble alkali metal complexing agent and hydrazine or its derivatives. A method for electrolessly plating gold onto a nickel substrate is also disclosed.

Abstract: A method of catalytically activating refractory metal surfaces for the subsequent electroless plating of another metal thereon is disclosed, in which the refractory surface is treated while heated in a carburizing atmosphere under conditions which cause the formation of refractory metal carbides on the refractory surface.

Abstract: A method of applying nickel directly to a non-activated tungsten surface is disclosed, in which the tungsten surface is immersed in an aqueous electroless nickel plating bath containing a water-soluble nickel salt; ethylenediaminetetraacetic acid; hydrazine; and monoethanolamine for a period of time sufficient to deposit a layer of nickel on the tungsten surface.

Abstract: An electrode for a carbonate fuel cell and method of making same wherein a substantially uniform mixture of an electrode-active powder and porous ceramic particles suitable for a carbonate fuel cell are formed into an electrode with the porous ceramic particles having pores in the range of from about 1 micron to about 3 microns, and a carbonate electrolyte is in the pores of the ceramic particles.

Abstract: A plurality of electrolyte carbonate-coated ceramic particle which does not differ significantly in size from that of the ceramic particle and wherein no significant portion of the ceramic particle is exposed is fabricated into a porous tape comprised of said coated-ceramic particles bonded together by the coating for use in a molten carbonate fuel cell.

Abstract: A plurality of electrolyte carbonate-coated ceramic particle which does not differ significantly in size from that of the ceramic particle and wherein no significant portion of the ceramic particle is exposed is fabricated into a porous tape comprised of said coated-ceramic particles bonded together by the coating for use in a molten carbonate fuel cell.

Abstract: A compact comprised of a mixture of lithiated nickel oxide powder and lithiated copper oxide powder is fired in air producing a sintered body useful as a cathode in a molten carbonate fuel cell.

Abstract: A cathode composite useful for a molten carbonate fuel cell comprised of a porous sintered cathode having a porous sintered bubble pressure barrier integrally sintered to one face thereof, said cathode composite having a porosity ranging from about 25% by volume to about 75% by volume of the total volume of said composite, said cathode having a porosity ranging from about 25% by volume to about 75% by volume of the total volume of said cathode, said pressure barrier having a porosity ranging from about 25% by volume to about 75% by volume of the total volume of said barrier, said cathode having a median pore size ranging from in excess of one micron to about 10 microns, said barrier having a median pore size significantly smaller than that of said cathode, said cathode and said pressure barrier being comprised of from about 10 weight % to about 90 weight % Li.sub.x Ni.sub.(1-x) O/balance Li.sub.y Cu.sub.(1-y) O, where x and y each ranges from about 0.005 to about 0.25.

Abstract: A sintered porous electrode useful for a molten carbonate fuel cell is produced which is composed of a plurality of 5 wt. % to 95 wt. % nickel balance copper alloy encapsulated ceramic particles sintered together by the alloy.