A method for manufacturing a printed circuit board includes forming a through hole in an insulating layer of the printed circuit board, filling the through hole by plating to form a plating layer on the insulating layer, and removing the plating layer from the insulating layer; and forming a circuit pattern on the insulating layer.

A method for selective metallization includes: selectively adsorbing catalytic nanoparticles onto an imprint mold to form a selectively adsorbed catalytic nanoparticle (SACN) mold; using the SACN mold in an imprinting process to synchronously transfer a pattern and the catalytic nanoparticles onto a film; separating the film from the SACN mold; and selectively depositing metal onto the film based on the pattern transferred to the film.

A circuit board has a dielectric core, a foil top surface, and a thin foil bottom surface with a foil backing of sufficient thickness to absorb heat from a laser drilling operation to prevent the penetration of the thin foil bottom surface during laser drilling. A sequence of steps including a laser drilling step, removing the foil backing step, electroless plating step, patterned resist step, electroplating step, resist strip step, tin plate step, and copper etch step are performed, which provide dot vias of fine linewidth and resolution.

A printed wiring board includes a conductor layer including first and second pads, a coating layer covering the conductor layer and having first opening exposing the first pad and second opening exposing the second pad, and metal bumps including a first bump on the first pad and a second bump on the second pad such that the first and second bumps protrude from the coating layer. The first and second openings are formed such that diameter of the second pad is smaller than diameter of the first pad. The first and second bumps are formed such that height of protruding portion of the first bump from the surface of the coating layer is substantially equal to height of protruding portion of the second bump from the surface of the coating layer and that the second bump covers an area of the coating layer on the surface surrounding the second opening.

A method for manufacturing a printed circuit board (PCB) with high component density includes at least two reinforcing plates, at least two connecting plates, a first circuit board unit, and a second circuit board unit. The reinforcing plate includes a supporting portion, a first connecting portion, and a second connecting portion. The first connecting portion and the second connecting portion connect to ends of the supporting portion. The connecting plates are bendable circuit boards. Each connecting plate is attached to the supporting portion, the first connecting portion, and the second connecting portion of a reinforcing plate. The first circuit board unit is fixed and electrically connected to a connecting plate away from first connecting portion. The second circuit board unit is fixed and electrically connected to a connecting plate away from the second connecting portion.

A base material for a printed circuit board includes: an insulating base film; a sintered layer that is layered on at least one side surface of the base film and that is formed of a plurality of sintered metal particles; an electroless plating layer that is layered on a surface of the sintered layer that is opposite to the base film; and an electroplating layer that is layered on a surface of the electroless plating layer that is opposite to the sintered layer, wherein an arithmetic mean height Sa of the surface of the electroless plating layer opposite to the sintered layer is greater than or equal to 0.001 m and less than or equal to 0.5 m.

A printed circuit board includes a substrate having a first surface and a second surface, opposite to the first surface, and having a through-portion penetrating between the first surface and the second surface; and a through-via disposed in at least a portion of the through-portion, wherein the through-via includes a first metal layer having a first groove portion facing an interior of the through-portion from the first surface of the substrate and a second groove portion facing the interior of the through-portion from the second surface of the substrate, and the first metal layer has a first region, and a second region, having different average grain sizes.

A wiring board includes a wiring layer; a diffusion suppressing layer that. covers the wiring layer and suppresses diffusion of a metal component of the wiring layer; a base metal layer that covers the diffusion suppressing layer; and a passivation layer that covers the base metal layer.

Disclosed is a surface treated copper foil in which the dropping of the roughening particles from the roughening treatment layer provided on the surface of the copper foil is favorably suppressed. Also disclosed is a surface treated copper foil, comprising a copper foil, a roughening treatment layer on one surface, and/or another roughening treatment layer the other surface of the copper foil, wherein a height of roughening particles of the roughening treatment layer is 5 to 1000 nm from the surface, a color difference E*ab according to JIS Z 8730 of a surface of a side of the roughening treatment layer is 65 or less, and a glossiness of the TD of the surface of the side of the roughening treatment layer is 70% or less.

A circuit board pad resonance control system includes a board. A signal transmission line is included on the board. A plurality of connector pads are positioned on the board. A first connector pad receives the signal transmission line adjacent a first end of that connector pad. The first connector pad includes a mounting surface that mounts directly to a coupling element that is configured to couple a subsystem to the board, and reduces a resonance that is produced by an open portion of a signal transmission path that is created when the coupling element is directly mounted to the mounting surface of the first connector pad in a first orientation. In a specific example, the mounting surface may include a plurality of protrusions, a plated surface, and/or a mask that reduces the conductivity of the connector pad which reduces signal integrity issues due to resonance.