Abstract:
An in situ method for forming a bypass capacitor element internally within a PCB comprising the steps of arranging one or more uncured dielectric sheets with conductive foils on opposite sides thereof and laminating the conductive foils to the dielectric sheet simultaneously as the PCB is formed by a final lamination step, the conductive foils preferably being laminated to another layer of the PCB prior to their arrangement adjacent the dielectric sheet or sheets, the dielectric foils even more preferably being initially laminated to additional dielectric sheets in order to form multiple bypass capacitive elements as a compound subassembly within the PCB. A number of different dielectric materials and resins are disclosed for forming the capacitor element. A dielectric component in the capacitor element preferably includes dielectric material and thermally responsive material, the thermally responsive material either forming a carrier for the dielectric material or formed as two separate sheets on opposite sides of a sheet of the dielectric material.
Abstract:
A method of preparing an adhesive composite is provided where a expanded fluoropolymer having nodes and interconnected fibrils with a void volume formed from the node and interconnected fibril structure is at least partially filled with a paste formed from a thermoset or thermoplastic adhesive and a particulate inorganic filler, sufficient adhesive and filler are present to provide a composite containing between about 5 to about 40 volume percent expanded fluoropolymer; 5-85 volume percent inorganic filler; and 10-95 volume percent of adhesive and filler, the adhesive and filler being contained within the voids of the expanded fluoropolymer. In the composite, the ratio of the mean flow pore size of the expanded fluoropolymer to the largest particle size of the filler is at least about 2 and/or the ratio of the minimum pore size of the expanded fluoropolymer to the largest particle size of the filler is at least about 1.4 within the composite.
Abstract:
The present invention is an improved adhesive sheet (also known as a "bond ply," "bond film," or "prepreg") material suitable for bonding together electric circuit boards and other electrical components. The adhesive sheet of the present invention comprises a combination of a porous expanded polytetrafluoroethylene (PTFE), a ceramic filler, and a thermoset resin imbibed within the porous PTFE structure. By employing a fill of less than about 60% by weight of resin, the adhesive sheet has exceptionally good performance characteristics while being vastly easier to process.
Abstract:
Fillers coated with a fluorosilane coating are provided as well as compositions containing the coated fillers. Compositions are especially suitable for substrates for printed circuit boards and cards.
Abstract:
A board (10) for testing an integrated circuit disposed on a semiconductor wafer. The board contains a plurality of substantially parallel signal layers (14) and power planes (16) that are supported and electrically isolated by a dielectric material (12). One or more constraint layers (18,20) are disposed in the dielectric material, and the constraint layers have a coefficient of thermal expansion of about 1-6 ppm/.degree.C. In a preferred embodiment, the dielectric material is a fluoropolymer with-a ceramic or silica filler, and the constraint layers are an iron-nickel alloy of about 30-40 percent nickel by weight. The board has thermal expansion characteristics substantially similar to silicon to ensure good contact to a silicon wafer during burn-in testing.
Abstract:
There is provided a process for producing conductive areas through selected portions of the Z axis of a porous planar material. In the process, the planar material is sensitized to the reception of electroless metal with an electroless metal deposition solution. The planar material is provided throughout the selected Z axis areas with a metal salt composition which on exposure to radiant energy, such as light, electron beams, x-ray, and the like, so as to convert the metal cations to metal nuclei. The metal nuclei is then displaced with a more stable metal, such as palladium and then the material is electrolessly plated. The metalized planar material is then imbibed with a resin at such a percentage so that adhesion is provided between two substrates without loss of conductivity in the Z axis.
Abstract:
Disclosed is a parallel processor packaging structure and a method for manufacturing the structure. The individual logic and memory elements are on printed circuit cards. These printed circuit boards and cards are, in turn, mounted on or connected to circuitized flexible substrates extending outwardly from a laminate of the circuitized, flexible substrates. Intercommunication is provided through a switch structure that is implemented in the laminate. The printed circuit cards are mounted on or connected to a plurality of circuitized flexible substrates, with one printed circuit card at each end of the circuitized flexible circuit. The circuitized flexible substrates connect the separate printed circuit boards and cards through the central laminate portion. This laminate portion provides XY plane and Z-axis interconnection for inter-processor, inter-memory, inter-processor/memory element, and processor to memory bussing interconnection, and communication. The planar circuitization, as data lines, address lines, and control lines of a logic chip or a memory chip are on the individual printed circuit boards and cards, which are connected through the circuitized flex, and communicate with other layers of flex through Z-axis circuitization (vias and through holes) in the laminate.
Abstract:
Disclosed is a parallel processor packaging structure and a method for manufacturing the structure. The individual logic and memory elements are on printed circuit cards. These printed circuit boards and cards are, in turn, mounted on or connected to circuitized flexible substrates extending outwardly from a laminate of the circuitized, flexible substrates. Intercommunication is provided through a switch structure that is implemented in the laminate. The printed circuit cards are mounted on or connected to a plurality of circuitized flexible substrates, with one printed circuit card at each end of the circuitized flexible circuit. The circuitized flexible substrates connect the separate printed circuit boards and cards through the central laminate portion. This laminate portion provides XY plane and Z-axis interconnection for inter-processor, inter-memory, inter-processor/memory element, and processor to memory bussing interconnection, and communication. The planar circuitization, as data lines, address lines, and control lines of a logic chip or a memory chip are on the individual printed circuit boards and cards, which are connected through the circuitized flex, and communicate with other layers of flex through Z-axis circuitization (vias and through holes) in the laminate.
Abstract:
The improved moistureproof structure for a module circuit is characterized in that a porous film conditioned to have an apparent relative dielectric constant of no more than 2.0 is coated over a stripline a high-frequency circuit, or a high-frequency device formed on a substrate, which porous film may in turn be provided with a resin coating material. The structure insures that the module circuit is moistureproof, thereby protecting it against corrosion to improve its operational reliability without affecting its electrical characteristics.
Abstract:
Methods of fabricating multilayer circuits are presented. In accordance with the present invention, a plurality of circuit layers comprised of a dielectric substrate having a circuit formed thereon are stacked, one on top of the other. The dielectric substrate is composed of a polymeric material capable of undergoing fusion bonding such as a fluoropolymeric based substrate. The circuits each include a layer of a noble metal at, at least, selected exposed locations. Once stacked the circuits are subjected to lamination under heat and pressure to simultaneously fuse all of the substrate and diffuse conductive layers together to form an integral multilayer circuit having solid conductive interconnects.