A method for manufacturing a printed wiring board includes forming through holes in a double-sided copper-clad laminated plate such that a high-density region of the through holes and a low-density region of the through holes are formed, forming an electrolytic plating film on a copper foil of the plate in the high-density and low-density regions, forming a masking resist to mask the plating film in the high-density region, etching the plating film in the low-density region exposed from the resist such that the plating film in the low-density region is thinned, peeling off the resist from the plating film in the high-density region, and forming a conductor circuit including the copper foil and the plating film in the high-density and low-density regions. The forming of the plating film on the copper foil of the plate includes forming the plating film in the through holes in the high-density and low-density regions.

A printed circuit board includes: a first insulating layer having a recess portion in one surface of the first insulating layer; a first circuit pattern embedded in the first insulating layer and being in contact with a lower surface of the recess portion; a second insulating layer disposed on the one surface of the first insulating layer to be disposed in at least a portion of the recess portion; and a via penetrating through at least a portion of the second insulating layer, disposed in the recess portion, and connected to the first circuit pattern.

A method of manufacturing a printed circuit board a includes preparing an insulating substrate on which a first metal layer is formed, stacking a resist laminate having a plurality of layers on the first metal layer, forming an opening exposing a portion of the first metal layer by patterning the stacked resist laminate having the plurality of layers, forming a second metal layer on the exposed portion of the first metal layer, removing the patterned resist laminate having the plurality of layers, and etching at least another portion of the first metal layer.

The invention discloses a method of improving a wire structure of a circuit board, comprising the following steps: providing a multi-layer circuit board, including an inner circuit and a surface circuit; forming an opening to expose the inner circuit; forming a first circuit layer in the opening; removing the first circuit layer, the first conductive circuit, and the surface circuit on the multi-layer circuit board and removing a part of the first circuit layer in the opening; forming an adhesion promoter layer in the opening and on the multi-layer circuit board; forming a second conductive circuit on the adhesion promoter layer and on the first conductive circuit layer in the opening; forming a photoresist layer on the second conductive circuit layer; forming a second circuit layer in the opening and on the multi-layer circuit board, and removing the photoresist layer and a part of the second conductive circuit.

An insulating sheet for use in forming an insulating layer of an interconnect substrate includes a semi-cured insulating resin layer, a semi-cured protective resin layer laminated on an upper surface of the insulating resin layer, and a cover layer laminated on an upper surface of the protective resin layer, wherein the protective resin layer has lower resistance to a predetermined solution than the insulating resin layer has, the predetermined solution being capable of dissolving the insulating resin layer and/or the protective resin layer.

A printed wiring board includes an insulating layer, and a conductor layer including a solid layer and wirings. The solid layer has an opening part. The wirings are formed in the opening part. The opening part includes first and second opening parts. The wirings include first and second wirings. The first wiring has a first land, a first portion, and a second portion. The second wiring has a second land, a third portion, and a fourth portion extending in parallel to the second portion. A first boundary between the first and second portions is in the second opening part. The first portion is bending at the first boundary and increasing distance between the first and second wirings. A second boundary between the third and fourth portions is in the second opening part. The third portion is bending at the second boundary and increasing distance between the first and second wirings.

A connection method for a chip and a circuit board includes: placing the circuit board on the chip, the circuit board having a first surface in contact with the chip having a plurality of contacts, and the circuit board having a plurality of through holes aligned with the plurality of contacts respectively; placing a mask on a second surface of the circuit board, the mask having a plurality of openings aligned with the plurality of through holes respectively; covering a surface of the mask with a conductive adhesive to fill the plurality of through holes with the conductive adhesive; and keeping portions of the conductive adhesive that are respectively in the plurality of through holes to be spaced apart from each other. The portions of the conductive adhesive that fill the plurality of through holes remain to provide an electrical connection between the circuit board and the chip.

An electronic device and a method for manufacturing a flexible circuit board are provided. The electronic device includes the flexible circuit board. The flexible circuit board includes a first flexible substrate, a first seed layer, a first conductive layer, and a second seed layer. The first seed layer is disposed on the first flexible substrate. The first conductive layer is disposed on the first seed layer. The second seed layer is disposed on the first conductive layer. The first seed layer is in contact with the first conductive layer.

A system for providing selective adhesion printed circuit board (PCB) production comprises a conveyor mechanism, a curing system, and a computer. The conveyor mechanism is configured to convey a series of selective adhesion blanks, wherein each selective adhesion blank is utilized to produce a PCB and includes a flexible film, a substrate, a conductive layer, and a curable adhesive. The conductive layer is formed from electrically conductive material and adhered to the substrate. The curable adhesive is positioned between the flexible film and the conductive layer and is configured to selectively bond with the conductive layer when the curable adhesive is cured. The curing system is configured to cure the curable adhesive. The computer includes a processing element configured or programmed to: receive a plurality of PCB designs, and direct the curing system to cure the curable adhesive of a plurality of selective adhesion blanks for each PCB design.

A printed wiring board includes a first conductor layer, a resin insulating layer formed on the first conductor layer, a second conductor layer formed on a surface of the resin insulating layer and including a signal wiring, and a via conductor formed in the resin insulating layer such that the via conductor is connecting the first conductor layer and the second conductor layer. The resin insulating layer has an opening such that the opening is exposing a portion of the first conductor layer and that the via conductor is formed in the opening of the resin insulating layer, and the resin insulating layer includes inorganic particles and resin such that the resin is forming the surface of the resin insulating layer.