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 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 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loop for substantially continuously withdrawing solution from the tank and removing particulate matter from the withdrawn solution and a system for removing surface impurities from the solution.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:
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 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 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:
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:
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.