A rigid-flexible circuit board which can be simply and easily manufactured includes a wiring substrate, two adhesive layers, and two outer conductive wiring layers. The wiring substrate defines an opening penetrating and splitting the wiring substrate. The two outer conductive wiring layers are stacked on opposite surfaces of the wiring substrate. Each of the two adhesive layers is bonded between one of the two outer conductive wiring layers and the wiring substrate and infills the opening. A simplified method for manufacturing the rigid-flexible circuit board is also disclosed.

A circuit board structure includes a first sub-board including a plurality of circuit patterns, a second sub-board including a plurality of pads, and a connecting structure layer having a plurality of through holes and including an insulating layer, first and second adhesive layers, and a plurality of conductive blocks. The first adhesive layer is directly connected to the first sub-board. The second adhesive layer is directly connected to the second sub-board. The through holes penetrate through the first adhesive layer, the insulating layer, and the second adhesive layer. The conductive blocks are located in the through holes. An upper surface and a lower surface of each conductive block are respectively lower than a first surface of the first adhesive layer and a second surface of the second adhesive layer relatively away from the insulating layer. Each circuit pattern contacts the upper surface, and each pad contacts the lower surface.

A method for manufacturing a multilayer wiring board is disclosed. The Method comprises a step (I) of preparing printed wiring boards having both electrical connection pads for establishing an electrical connection between the boards and non-connection pads for not establishing an electrical connection between the boards on the same plane; and a lamination step (II) of overlaying the boards so that the electrical connection pads face each other, and laminating the boards so that the boards are bonded to each other through a conductive material provided between the facing electrical connection pads. In the step (I), to at least one of surfaces faced when the boards are overlaid in the step (II), an insulating film having through holes formed in positions corresponding to the electrical connection pads on the surface is attached (Ia), and the conductive material is provided in the through holes (Ib).

The present invention relates to a patterned fiber substrate comprising: a fiber substrate; and a pattern consisting of a functional material and formed on the fiber substrate, wherein at least a part of the functional material that constitutes the pattern is present in inside of the fiber substrate, the fiber substrate has a contact angle of 100 to 170° with pure water on its surface, and the pattern has a narrowest line width of 1 to 3000 μm.

A honeycomb core includes a honeycomb substrate comprised of a number of sheets. A number of traces are printed onto the sheets of the honeycomb substrate. A number of integrated electronic devices are disposed within the honeycomb substrate. The integrated electronic devices are electrically coupled to the traces.

A multilayer substrate includes a laminate, first and second signal lines, first and second ground conductors, and interlayer connection conductors. The first and second signal lines extend along a transmission direction and include parallel extending portions that extend in parallel or substantially in parallel with each other. The first and second ground conductors sandwich the first and second signal lines in a laminating direction. The first and second ground conductors respectively include a first opening and a third opening between the signal lines when viewed from the laminating direction, and respectively include second openings and fourth openings disposed outside in a width direction orthogonal or substantially orthogonal to the transmission direction in the parallel extending portions when viewed from the laminating direction. The interlayer connection conductors are disposed in the transmission direction and at least between the signal lines.

A method includes forming a first redistribution line, forming a polymer layer including a first portion encircling the first redistribution line and a second portion overlapping the first redistribution line, forming a pair of differential transmission lines over and contacting the polymer layer, and molding the pair of differential transmission lines in a molding compound. The molding compound includes a first portion encircling the pair of differential transmission lines, and a second portion overlapping the pair of differential transmission lines. An electrical connector is formed over and electrically coupling to the pair of differential transmission lines.

A method may include forming a plurality of multilayer cores wherein each multilayer core comprises a sheet of cured dielectric material having a layer of metal on each side of the sheet of cured dielectric material, patterning each layer of metal in the plurality of multilayer cores to form wiring traces in each layer of metal, embedding a solder element in at least one sheet of a plurality of sheets of uncured dielectric material, wherein the solder element having a melting point temperature within a temperature range of a curing temperature of the uncured dielectric material, forming a printed circuit board by alternately stacking the plurality of multilayer cores with the plurality of sheets of uncured dielectric material between each multilayer core, laminating the stack of multilayer cores and sheets of uncured dielectric material to cause curing of the sheets of uncured dielectric material and melting of the solder element.

A board-to-board connecting structure which adds no significant thickness to a single printed circuit board includes a first circuit board and a second circuit board. The first circuit board includes first circuit substrate, adhesive layer, and second circuit substrate. The first circuit substrate includes first base layer, first inner wiring layer with first pad, and first outer wiring layer defining a receiving space. The second circuit substrate includes insulating layer and two second outer wiring layers. A conductive via in the second circuit substrate connects the two second outer wiring layers. The second circuit board includes second base layer and also two third outer wiring layers each with a second pad. The second circuit board is laterally disposed in the receiving space and one second pad connects to the conductive via and the other to the first pad.

Pastes are disclosed that are configured to coat a passage of a substrate. When the paste is sintered, the paste becomes electrically conductive so as to transmit electrical signals from a first end of the passage to ta second end of the passage that is opposite the first end of the passage. The metallized paste contains a lead-free glass frit, and has a coefficient of thermal expansion sufficiently matched to the substrate so as to avoid cracking of the sintered paste, the substrate, or both, during sintering.