Abstract:
A multi-layer blank for an electrical circuit board has at least one internal layer, which may constitute a common power supply or ground plane. The inner layer consists of an electrically conductive network extending throughout the area of the inner layer and formed by the repetition of an elementary predetermined pattern in two orthogonal directions. The elementary pattern has such a shape that adjacent patterns are in electrical contact so that the network is equipotential. The pattern is also of such a shape that there is formed a first regular grid of predetermined pitch p whose nodes constitute insulated sites and a second grid off-set by p/2 from the first grid in at least one of the orthogonal directions. The second grid has the same pitch p as the first one and has nodes one at least of which per elementary pattern is insulated while the other ones belong to the conducting network.
Abstract:
The present invention contemplates fabrication of a printed circuit board blank having a predetermined pattern of pads and interconnecting conductive pathways, preferably (but not necessarily) flush with the face of the insulating substrate. To fabricate a finished circuit board of any desired circuit configuration, the printed circuit board blank is coated with a photoresist and exposed so that upon development of the photoresist and etching in accordance with the developed pattern, the interconnecting conductive pathways between pads will be selectively etched away so that only those interconnects for the desired circuit pattern remain. While contact printing or image exposure systems may be used to expose the photoresist, computer controlled raster scan laser printers offer the combination of speed and versatility, as the predetermined starting matrix of the invention is highly conducive to computer aided design, and the percentage of circuit board area required for exposure is very small compared to normal copper-clad board fabrication techniques. For multilayer printed circuit boards, registration apertures are provided in each board layer for alignment purposes. Interconnects between boards are made by drilling through selective pads and plating the through holes to interconnect the various board layers. Isolation of any layer of any plated through hole may be obtained by either isolation of the pad (removal of all pad interconnects) at the through hole, or alternatively by etching a larger diameter in the pad which region will be filled with laminating adhesive during the lamination process to insulate the pad from the through hole copper plating.
Abstract:
An electrically conductive adhesive comprises electrically conductive particles mixed in a non-conductive base at such a mixing ratio that the conductive particles are not in contact with one another. When this adhesive is disposed between facing electrodes, it provides electric conductivity between the facing electrodes but maintains electric insulation in the lateral direction.
Abstract:
A prefabricated printed circuit board including a plurality of laminated planar-printed circuit-carrying members, each of the printed circuits having points of connection which are placed in congruent relation upon lamination, and having exposed planar surfaces which are covered over the entire area thereof with an etchable electrically conductive material such as copper. When employed to connect a specific group of components, the bonded layer is etched to a desired pattern, including points of electrical connection, following which the electrical components are mounted upon areas of the etched surface to be placed in electrical communication therewith.
Abstract:
A wiring board includes a core substrate having a structure including an insulating base material and a large number of filamentous conductors densely provided in the insulating base material and piercing the insulating base material in a thickness direction thereof. Pads made of portions of wiring layers are oppositely disposed on both surfaces of the core substrate and electrically connected to opposite ends of a plurality of filamentous conductors in such a manner that the pads share the filamentous conductors. A wiring connection between one surface side and the other surface side of the core substrate is made through the pads. The insulating base material is made of an inorganic dielectric. Pads made of portions of the wiring layers are disposed on both surfaces of the core substrate and electrically connected only to corresponding one end sides of different groups each formed of a plurality of filamentous conductors.
Abstract:
PROBLEM TO BE SOLVED: To reduce the cost by making a core substrate common and to improve flexibility of wiring design by increasing wiring density. SOLUTION: A wiring board 30 includes the core substrate 10 having a structure in which a number of linear conductors 12 are closely provided penetrating an insulating base 11 along its thickness. On both surfaces of the core substrate 10, pads P1, P2 comprising parts of a wiring layer 22 having both ends electrically connected sharing a plurality of linear conductors 12 are arranged opposite each other, and wiring connections with one surface side and the other surface side of the core substrate 10 are formed through the pads. Further, an insulating base 11 is made of an inorganic dielectric, and pads P3, P4 which include parts of wiring layers 22 each electrically connected to only one end side of linear conductors 12 for each group of a plurality of linear conductors 12 are arranged on both surfaces of the core substrate 10. COPYRIGHT: (C)2011,JPO&INPIT