Abstract: There is provided a composite material particularly suited for electrical and electronic applications having a metallic core with a desired surface finish. An acicular superficial coating layer having an apparent thickness of less than 275 angstroms is adjacent to at least a portion of the metallic core. The superficial coating layer is removable from the metallic core without appreciable change to the metallic core surface finish.

Abstract: There is disclosed a leadframe for electrically interconnecting a semiconductor device to external circuitry. The leadframe has an electrically conductive substrate that is coated with an oxidation resistant external layer. An intervening layer is disposed between a portion of the substrate and the external layer. The intervening layer is absent from the outer lead ends of the leadframe. Subsequent removal of the external layer from the outer lead ends enables a solder to directly contact the leadframe substrate.

Abstract: There is disclosed a process for the assembly of an electronic package in which the outer lead ends of a leadframe are solderable to external circuitry without the necessity of a tin or solder coat. An oxidation resistant layer is deposited on the leadframe prior to package assembly. The oxidation resistant layer is removed prior to outer lead soldering providing a clean, oxide free metallic surface for soldering.

Abstract: There is provided an anodizable aluminum substrate having an increased breakdown voltage. The increase in breakdown voltage is achieved by selecting an appropriate aluminum alloy and appropriate processing parameters. Sealing the anodic film increases the breakdown voltage by decreasing corrosion. A preferred sealant is an epoxy cresol novolac having a low room temperature viscosity that cures to a highly cross-linked polymer.

Abstract: There is disclosed an aqueous chemical solution that consists essentially of zinc ions, a source of hydroxides, and silicon ions. The ratio of silicon to zinc (Si:Zn) is, by weight from about 1:5 to about 1:250. Within the ratio range, the silicon ions inhibit precipitation of zinc from the chemical solution. This is particularly useful when the chemical solution is an electrolyte for the deposition of zinc or a zinc containing compound onto a metallic structure where a critical zinc content must be maintained to impart adequate adhesion of a coated substrate to a polymer adhesive.

Abstract: There is provided a lead frame with enhanced adhesion to a polymer resin. The lead frame is coated with a thin layer of containing chromium, zinc or a mixture of chromium and zinc. A mixture of chromium and zinc with the zinc-to-chromium ratio in excess of about 4:1 is most preferred. The coated lead frames exhibit improved adhesion to a polymeric resin.

Abstract: There is provided a lead frame with enhanced adhesion to a polymer resin. The lead frame is coated with a thin layer of containing a mixture of chromium and zinc. A mixture of chromium and zinc with the zinc-to-chromium ratio in excess of about 4:1 is most preferred. The coated lead frames exhibit improved adhesion to a polymeric resin.

Abstract: A method for the manufacture of an electronic circuit is provided. A substrate is provided with an indexing means and personality windows by etching. An adhesive is deposited on one surface of the substrate to coat at least those regions to be laminated to a metallic foil. The foil is bonded to the nonconductive substrate and patterned into a plurality of circuit traces. These steps may be repeated a plurality of time for a multi-metal layer structure.

Abstract: A method for the manufacture of an electronic circuit is provided. A non-conductive substrate is provided with an indexing means and personality windows by etching. An adhesive is deposited on one surface of the substrate to coat at least those regions to be laminated to a metallic foil. The foil is bonded to the non-conductive substrate and patterned into a plurality of circuit traces. Mechanical stamping of the substrate is not required providing a means to inexpensively manufacture small quantities of a desired circuit configuration.

Abstract: A multi-metal layer interconnect tape is provided. The tape is not supported by a dielectric carrier. A thin dielectric adhesive layer separates at least two self supporting metal foil layers. In one embodiment of the invention, conductive vias electrically interconnect leads formed in a first metal foil layer with ground and power circuits formed in a second metal foil layer. The metal foil layers are in close proximity so the vias have a low aspect ratio. The vias may be readily coated with continuous film of a conductive metal and are much easier to clean than conventional vias having significantly higher aspect ratios.

Abstract: The present invention relates to an addition to tin coating solutions for inhibiting the growth of tin whiskers. The addition comprises a concentration of a metal salt selected from the group consisting of palladium salt, silver salt, nickel salt, iron salt, cadmium salt, platinum salt, gold salt, indium salt, ruthenium salt and cobalt salt. In a preferred embodiment, the metal salt addition is either a palladium salt such as palladium chloride or a silver salt such as silver sulfate.

Abstract: The present invention relates to a process and apparatus for forming in situ surface treated metal foil. The apparatus includes a cathode and anode arranged and/or shaped to define a plating region characterized by a first zone having a first interelectrode gap and a second zone having a second interelectrode gap smaller than the first interelectrode gap. It has been found that by providing such an arrangement it is possible to generate in the first zone a localized current density below the limiting current density sufficient to plate metal foil onto the cathode and to simultaneously generate in the second zone a localized current density above the limiting current density sufficient to form dendrites on the freshly produced foil.

Abstract: The present invention relates to a technique for improving the tarnish and oxidation resistance of copper and copper base alloy materials. The technique of the present invention involves immersing the copper or copper base alloy material in a dilute aqueous chromic acid-phosphoric acid solution. After emerging from the chromic acid-phosphoric acid solution, the copper or copper base alloy material is preferably rinsed with a dilute aqueous caustic solution and dried. Copper and copper base alloy materials treated in accordance with the present invention have particular utility in printed circuit applications.

Abstract: The present invention relates to a system and a process for producing improved quality electrodeposited and/or treated metal or metal alloy foil to be used in electrical and electronic applications. The quality of the foil being produced and/or treated by the system is improved by providing each treatment tank in the system with a dual filtration system. The dual filtration system for each tank comprises a filter conditioning loop for substantially continuously withdrawing solution from the tank and removing particulate matter from the withdrawn solution and a system for removing surface impurities from the solution. In a first embodiment, the surface impurities removing system comprises an off-line solution filtration and replenishment system. In a second embodiment, the surface impurities removing system comprises a skimmer floating on the surface of the solution. The present invention has particular utility in systems for producing electrodeposited and/or treated copper foils.

Abstract: The present invention relates to a technique for improving the adhesive properties of a metal or metal alloy material by reducing the number of bare spots and unplated regions on each treated surface of the metal or metal alloy material. The technique comprises electrolytically forming a substantially uniform metal oxide layer on at least one surface of the material, chemically converting the oxide layer into a substantially uniform layer of fresh metal, and thereafter electrolytically forming a plurality of dendritic structures on the at least one surface. The technique of the present invention has particular utility in improving the adhesive properties of wrought copper and copper alloy foils. An apparatus for performing the technique is also described.

Abstract: The present invention relates to a treatment for improving the laminate adhesion of metal and metal alloy materials, particularly copper and copper alloy foils. The treatment comprises electrolytically forming a plurality of dendrites on a surface of the metal or metal alloy material and bonding the dendrites thereto. The dendrites are formed on and bonded to the metal or metal alloy material surface by one or more treatment anodes positioned at an angle to the material being treated and a single current source.

Abstract: The present invention relates to a system and a process for producing improved quality electrodeposited and/or treated metal or metal alloy foil to be used in electrical and electronic applications. The quality of the foil being produced and/or treated by the system is improved by providing each treatment tank in the system with a dual filtration system. The dual filtration system for each tank comprises a filter conditioning loop for substantially continuously withdrawing solution from the tank and removing particulate matter from the withdrawn solution and a system for removing surface impurities from the solution. In a first embodiment, the surface impurities removing system comprises an off-line solution filtration and replenishment system. In a second embodiment, the surface impurities removing system comprises a skimmer floating on the surface of the solution. The present invention has particular utility in systems for producing electrodeposited and/or treated copper foils.

Abstract: The present invention relates to a treatment for improving the adhesive properties of metallic foils to be used in electrical and electronic applications. The treatment of the present invention comprises applying a light substantially uniform layer of metal to at least one surface of the metallic foil just prior to the formation of a plurality of dendritic structures on the surface. The metal layer renders the surface or surfaces to be treated more uniformly electrochemically active and consequently more receptive to the subsequent dendritic treatment. The treatment of the present invention has particular utility in improving the adhesive properties of wrought copper and copper alloy foils. An apparatus for performing the present treatment is also described.

Abstract: The present invention relates to a system for aligning a plurality of rollers in a metal or metal alloy foil production line. The alignment system comprises a reference frame having a longitudinal dimension parallel to the direction of foil travel through the production line and an optical alignment system movably mounted to the frame. The optical alignment system comprises a laser beam generator, beam splitters and a mirror for generating an orthogonal reference frame for aligning each foil contacting roller in the production line.