Abstract: This invention discloses compositions and methods that afford sustainable deposition of electroless copper coatings, using aqueous hypophosphite compositions as opposed to formaldehyde (FA) The invention thus obviates the use of nefarious FA, a suspected carcinogen, presently the predominant reducer for plating electroless copper. The patent enables to plate “heavy” copper thicknesses currently unobtainable by the prior art teachings of electroless copper processes, that are based on hypophosphite reducers. The process and compositions of this patent are especially attractive for horizontal plating machines, currently using (FA) compositios. It is also beneficial for plating electroless copper on aluminum or zinc diecastings The patent further envisions electroless plating of silver in a cyanide-free composition.

Abstract: This invention teaches deposition of a corrosion-barrier layer onto a copper substrate, which minimizes copper corrosion even if the final immersion top layer is not without pinholes. Such barrier layer can comprise a copper conversion coating, corrosion resistant immersion deposited metal coatings such as palladium, gold, etc. The deposition of a barrier layer is generally followed by immersion deposition of a metal plate such as for example silver, tin, or others, designed to promote solderability. The patent also envisions the barrier layer as a “stand alone” final finish, serving both as a corrosion barrier layer and at the same time will promote solderability. The patent further teaches ways to minimize the problems of black nickel formation in the field, when the final finish is an electroless Ni—P (EN), topped with immersion gold.

Abstract: This patent discloses embodiments that overcome the deficiencies of pinholes and porosities that plague immersion deposited metal coatings deposited as a final finish to throughole copper Printed Wiring Boards(PWB'S). The patent focuses particularly on silver immersion plated PWB's, where pinholes in the silver film lead to creep corrosion, resulting in failure of costly PWB assemblies in the field. Said pinholes and microvoids are repaired by capping them with electrolessly plated metal, preferably silver.

Abstract: A process is described for the direct production of an imaged pattern of resist on a substrate surface (such as a pattern of etch-resistant organic resin material on the surface of a copper-clad dielectric in connection with a printed circuit board (PCB) fabrication process or in the process of producing printed plates), which process utilizes thermo-resists rather than photoresists, i.e., compositions which undergo thermally-induced, rather than photo-induced, chemical transformations. A film of thermo-resist composition applied to the substrate surface is scanned by a focused heat source (e.g., a thermal laser emitting in the IR region) in a predetermined pattern, without a phototool, to bring about localized thermally-induced chemical transformations of the composition which either directly produce the resist pattern or produce in the film a developable latent image of the pattern.

Abstract: A process is described for the direct production of an imaged pattern of resist on a substrate surface (such as a pattern of etch-resistant organic resin material on the surface of a copper-clad dielectric in connection with a printed circuit board (PCB) fabrication process or in the process of producing printed plates), which process utilizes thermo-resists rather than photoresists, i.e., compositions which undergo thermally-induced, rather than photo-induced, chemical transformations. A film of thermo-resist composition applied to the substrate surface is scanned by a focused heat source (e.g., a thermal laser emitting in the IR region) in a predetermined pattern, without a phototool, to bring about localized thermally-induced chemical transformations of the composition which either directly produce the resist pattern or produce in the film a developable latent image of the pattern.

Abstract: A process is described for the direct production of an imaged pattern of resist on a substrate surface (such as a pattern of etch-resistant organic resin material on the surface of a copper-clad dielectric in connection with a printed circuit board (PCB) fabrication process or in the process of producing printed plates), which process utilizes thermo-resists rather than photoresists, i.e., compositions which undergo thermally-induced, rather than photo-induced, chemical transformations. A film of thermo-resist composition applied to the substrate surface is scanned by a focused heat source (e.g., a thermal laser emitting in the IR region) in a predetermined pattern, without a phototool, to bring about localized thermally-induced chemical transformations of the composition which either directly produce the resist pattern or produce in the film a developable latent image of the pattern.

Abstract: The present invention relates to a process for the manufacture of printed circuit boards. The method contemplates a novel processing sequence for this manufacturing process which method is particularly versatile in reducing the number of steps and variety of chemicals currently necessary to produce the circuit boards.

Abstract: A positive working deep UV sensitive photoresist which provides improved critical dimension stability during prolonged periods of post exposure delay before baking comprises an acid stable polymer which is insoluble in water but normally soluble in an aqueous alkaline medium, a photoinitiator which generates acid upon exposure to actinic radiation, and a mixed carbonate ester of tertiary butyl alcohol and a polyhydric phenol which is an acid labile compound which inhibits the dissolution of the normally soluble polymer in said alkaline medium.

Abstract: In a mechanical plating process, oxidation-prone metals, such as aluminum, titanium, magnesium, and mixtures thereof, can be applied to metal substrates without the corrosion problems encountered in the prior art. To avoid such problems, the substrate is plated with the oxidation-prone metal and relatively minor amounts of an immersion metal and, optionally, a protective metal. The immersion metal which can be salts or oxides of metals selected from the group consisting of tin, copper, nickel, cadmium, zinc, lead, and mixtures thereof coats the oxidation-prone metal in forming a mechanical plating coating and prevents formation of an oxide layer on the oxidation-prone metal. The protective metal which may be selected from the group consisting of zinc, cadmium, and mixtures thereof prevents oxidation of the plated metal substrate when exposed to the environment. An etching agent is used either prior to and/or during mechanical plating.

Abstract: In a mechanical plating process, oxidation-prone metals, such as aluminum, titanium, magnesium, and mixtures thereof, can be applied to metal substrates without the corrosion problems encountered in the prior art. To avoid such problems, the substrate is plated with the oxidation-prone metal and relatively minor amounts of an immersion metal and, optionally, a protective metal. The immersion metal which can be salts or oxides of metals selected from the group consisting of tin, copper, nickel, cadmium, zinc, lead, and mixtures thereof coats the oxidation-prone metal in forming a mechanical plating coating and prevents formation of an oxide layer on the oxidation-prone metal. The protective metal which may be selected from the group consisting of zinc, cadmium, and mixtures thereof prevents oxidation of the plated metal substrate when exposed to the environment. An etching agent is used either prior to and/or during mechanical plating.

Abstract: Chipping, flaking, and cracking of mechanical galvanizing coatings applied on metal substrates is prevented by interposing between successive layers of plating metal, which are used in galvanizing the metal substrate, a layer of cushioning metal. Each interposed layer of cushioning metal imparts malleability to the coating such that chipping, cracking, and flaking is prevented or substantially reduced. The plating metal is preferably zinc, while the cushioning metal is preferably tin, lead, or mixtures thereof.

Abstract: Photo resist image layers, particularly those used for high resolution geometries in microelectronic applications, are stabilized against distortion or degradation by the heat generated during subsequent etching, ion implantation processes and the like, by the application of a film of a thermally stabilizing agent prior to post-development bake of the image layer. High temperature resistant film forming polymers, of which gelatin and gelatin hydrolysates are preferred examples, are employed as thermally stabilizing agents.The process serves to achieve thermal stabilization of the photoresist image layer without significantly affecting the ease of subsequent stripping of the layer. It is particularly effective when used to thermally stabilize positive resist images derived from photoresist systems based on novolak resins.

Abstract: Chipping, flaking, and cracking of mechanical galvanizing coatings applied on metal substrates is prevented by interposing between successive layers of plating metal, which are used in galvanizing the metal substrate, a layer of cushioning metal. Each interposed layer of cushioning metal imparts malleability to the coating such that chipping, cracking, and flaking is prevented or substantially reduced. The plating metal is preferably zinc, while the cushioning metal is preferably tin, lead, or mixtures thereof.

Abstract: Photo resist image layers, particularly those used for high resolution geometries in microelectronic applications, are stabilized against distortion or degradation by the heat generated during subsequent etching, ion implantation processes and the like, by the application of a film of a thermally stabilizing agent prior to post-development bake of the image layer.The process serves to achieve thermal stabilization of the photoresist image layer without significantly affecting the ease of subsequent stripping of the layer. It is particularly effective when used to thermally stabilize positive resist images derived from photoresist systems based on novolak resins.

Abstract: A method of electroless deposition of metal on a non-conductive substrate is disclosed and comprises treating a substrate prior to electroless deposition with a catalyst composition containing a mixed tin-palladium catalyst. An improvement in metal deposition is obtained by contacting the treated substrate with an alkaline accelerator bath containing an agent which oxidizes the tin.

Abstract: Electroless copper deposition solutions, and method of electrolessly depositing copper onto a workpiece using these solutions, are disclosed. The solutions contain, in addition to water as the usual solvent, a soluble source of copper ions, a complexing agent or mixture of agents to maintain the copper in solution, and a copper reducing agent effective to reduce the copper ions to metallic copper as a deposit or plating on a prepared surface of a workpiece brought into contact with the solution.

Abstract: Electroless copper deposition solutions, and method of continuously electrolessly depositing copper onto a workpiece using these solutions, are disclosed. The solutions contain, in addition to water as the usual solvent, a soluble source of copper ions, a complexing agent or mixture of agents to maintain the copper in solution, a non-formaldehyde copper reducing agent, such as hypophosphite, effective to reduce the copper ions to metallic copper as a deposit or plating on a prepared surface of a workpiece brought into contact with the solution, and a soluble source of non-copper metallic ions, such as nickel or cobalt ions, which act as an autocatalysis promoter to enable continuous plating using the solutions. The solutions are maintained in an alkaline condition and preferably in a pH range of 11-14 through the addition of pH adjusters.

Abstract: Electroless copper deposition solutions, and method of electrolessly depositing copper onto a workpiece using these solutions, are disclosed. The solutions contain, in addition to water as the usual solvent, a soluble source of copper ions, a complexing agent or mixture of agents to maintain the copper in solution, and a copper reducing agent effective to reduce the copper ions to metallic copper as a deposit or plating on a prepared surface of a workpiece brought into contact with the solution.

Abstract: A process is disclosed comprising laminating an anodically treated aluminum surface against a thermoset plastic substrate, whereby the surface of the substrate after chemically removing the aluminum has an improved affinity for the adherence thereon of electrolessly deposited metal films.

Abstract: An improvement is obtained in the bond strength between members of a laminate comprising a plastic substrate and a metal film through a process of first laminating to the plastic substrate a thin, sacrificial, anodized metal foil while providing at the interface prior to laminating of the foil to the plastic at least a mono molecular film of an organic silicon compound. After laminating the treated metal foil to the substrate under heat and pressure, the foil is chemically stripped from the substrate, leaving a surface of improved receptivity for conventional electroless plating and electroplating procedures, or other metallizing techniques. The final metal film when applied to the substrate exhibits consistently better adhesive strength than is obtained without the organic silicon treatment of the interface, especially in respect to adhesive strength at elevated temperature.