Abstract: The present invention relates to new methods for delivering solutions during electronic device manufacture. Methods of the invention include delivering metallization solutions to the device at an angle of less than 90 degrees with the surface of the device. The method may further comprise partially treating the device by delivering the metallization solutions from above the device, turning the device over, and then completing treatment by delivering the metallization solutions from below the article. The method is particularly useful in the formation of printed circuit boards and other electronic packaging devices having through-holes and blind vias.

Abstract: A microetch composition for a circuit board containing sulfuric acid in combination with a carboxylic acid having 2 to 6 carbon atoms, wherein the volume of the carboxylic acid is preferably greater than the amount of sulfuric acid. The method discloses the contacting of a electrically conductive polymer with the microetch composition disclosed above to expose copper underlying the electrically conductive polymer.

Abstract: The invention relates to a metal sulfide dispersion used for electroplating nonconductors such as substrates used for the formation of a printed circuit board. A printed circuit board made using the dispersion could have metallized through-holes comprising electrodeposited copper on the walls of the holes with an adsorbed layer of metal sulfide particles between the circuit board base material and the copper on the walls of the through-holes. The metal sulfide is characterized by spherical particles having a mean diameter of less than 100 nanometers and a particle size distribution where less than 10 percent of the particles within the dispersion have a diameter twice that of the mean diameter of all particles within the dispersion.

Abstract: A process for electroplating a substrate having a surface comprising metallic and non-metallic regions. The process is characterized by selectively forming a protective film over the metallic regions of the substrate surface and forming a sulfide coating selectively over the remaining portions of said substrate. The protective film enables selective sulfide formation only on metallic sites without formation of a sulfide coating on metallic surface regions of the substrate which would otherwise interfere with metal-to-metal bond during electroplating. Following formation of the sulfide conversion coating, the protective film is removed and the surface of the substrate electroplated.

Abstract: A method for electroplating a nonconducting surface using a metal oxide colloid. The process comprises contacting the surface of the nonconductor to be plated with a preformed colloid of a metal oxide to adsorb the colloid onto the surface of the nonconductor and then electroplating metal over the surface having the adsorbed metal oxide colloid. The process may include a step of reducing the metal oxide to a lower valent state prior to the step of metal plating.

Abstract: A process of electroplating comprising formation of a semiconductive coating over an article having both metallic and non-metallic portions, dissolving the metal surface underlying the semiconductive coating and removing the semiconductive coating by a high pressure water spray. The process is useful for the formation of printed circuit boards.

Abstract: A process for electroplating a nonconducting substrate comprising formation of a catalytic metal sulfide on the surface of a nonconducting substrate and electrolytic deposition of metal thereover. The catalytic metal chalcogenide is preferably palladium sulfide.

Abstract: A process for electroplating a nonconducting substrate comprising formation of a catalytic metal sulfide on the surface of a nonconducting substrate and electrolytic deposition of metal thereover. The catalytic metal chalcogenide is preferably palladium sulfide.

Abstract: A method for metal plating the surface of an article formed from an organic plastic. The method includes a step of passing a current between two electrodes immersed in an electrolyte containing dissolved plating metal. One of the electrodes is the article to be plated and is provided with a surface having areas of a catalytic metal chalcogenide conversion coating adjacent to and in contact with conductive areas. The metal sulfide is of a metal that would be catalytic to electroless metal deposition. The method is especially useful for the formation of printed circuit boards and is sufficiently versatile to permit formation of a printed circuit board by a process that involves pattern plating. In a preferred embodiment through holes in the circuit board substrate have their walls coated with a metal adhered to the plastic surface of the hole wall through an intermediate layer of tin-palladium sulfide.

Abstract: A method for metal plating the surface of an article formed from an organic plastic. The method includes a step of passing a current between two electrodes immersed in an electrolyte containing dissolved plating metal. One of the electrodes is the article to be plated and is provided with a surface having areas of a catalytic metal chalcogenide conversion coating adjacent to and in contact with conductive areas. The metal sulfide is of a metal that would be catalytic to electroless metal deposition. The method is especially useful for the formation of printed circuit boards and is sufficiently versatile to permit formation of a printed circuit board by a process that involves pattern plating.

Abstract: A method for metal plating the surface of a nonconducting article. The method includes a step of passing a current between two electrodes immersed in an electrolyte containing dissolved plating metal. One of the electrodes is the article to be plated and is provided with a surface having areas of a catalytic metal chalcogenide conversion coating. The metal chalcogenide is of a metal that would be catalytic to electroless metal deposition.

Abstract: A method for electroplating an article of manufacture comprising an electrically nonconductive body portion comprising treatment with sequentially a solution of a stannous salt; a solution containing a dissolved sulfide capable of reacting with said stannous salt; and a solution containing a dissolved platinum family metal; followed by electrolytic metal plating of the surface of the article.

Abstract: A method for metal plating the surface of an article formed from an organic plastic. The method includes a step of passing a current between two electrodes immersed in an electrolyte containing dissolved plating metal. One of the electrodes is the article to be plated and is provided with a surface having areas of a catalytic metal chalcogenide conversion coating adjacent to and in contact with conductive areas. In a preferred embodiment, the catalytic metal chalcogenide conversion coating is formed by treating the article with an acid colloidal solution of a tin-noble metal electroless metal plating catalyst and, subsequently, treating with a solution containing a dissolved sulfide to form a sulfide of the noble metal. The conversion coating allows the article to be directly electroplated. The method is especially useful for the formation of printed circuit boards and is sufficiently versatile to permit formation of a printed circuit board by a process that involves pattern plating.

Abstract: A catalytic adsorbate suspended in an aqueous solution comprising reduced catalytic metal on an organic suspending agent where the reduced catalytic metal has a maximum dimension not exceeding 500 angstroms. The catalytic adsorbate is useful for the electroless metal deposition of substrates that are non-catalytic to electroless metal deposition.

Abstract: A catalytic adsorbate suspended in an aqueous solution comprising reduced catalytic metal on an organic suspending agent where the reduced catalytic metal has a maximum dimension not exceeding 500 angstroms and the organic suspending agent is one capable of complexing with ions of the catalytic metal. The catalytic adsorbate is useful for the electroless metal deposition of substrates that are non-catalytic to electroless metal deposition.

Abstract: A catalytic adsorbate suspended in an aqueous solution comprising reduced catalytic metal on an organic suspending agent where the reduced catalytic metal has a maximum dimension not exceeding 500 angstroms. The catalytic adsorbate is useful for the electroless metal deposition of substrates that are non-catalytic to electroless metal deposition.