A wiring board includes a first wiring layer disposed on the first adhesion layer; and a second wiring layer disposed on the second adhesion layer, wherein a proportion of copper remaining in the first wiring layer is represented by C=B/A (%), where A is a total area of the first wiring layer, B is an area of copper in the first wiring layer, and C is a remaining copper ratio C defined as the proportion of copper remaining in the first wiring layer, and wherein when the remaining copper ratio C is set to 70 to 100%, the first adhesion layer is comprised of at least one material having a first predetermined Young's modulus, and the first wiring layer is comprised of at least one material having a second predetermined Young's modulus, the first predetermined Young's modulus being 0.1 to 0.85 times the second predetermined Young's modulus.

A printed circuit board stack structure includes a first printed circuit board, a second printed circuit board, and a filling glue layer. The first printed circuit board has at least one overflow groove, and includes first pads and a retaining wall surrounding the first pads. The second printed circuit board is disposed on the first printed circuit board, and includes second pads and conductive pillars located on some of the second pads. The conductive pillars are respectively connected to some of the first pads to electrically connect the second printed circuit board to the first printed circuit board. The filling glue layer fills between the first and the second printed circuit boards, and covers the first pads, the second pads, and the conductive pillars. The retaining wall blocks the filling glue layer so that a portion of the filling glue layer is accommodated in the overflow groove.

A method may include obtaining a printed circuit board (PCB) that includes a set of vias that include a set of stub regions. The PCB may include a set of layers perpendicular to the set of vias. The set of layers may include a signal layer and a ground layer. The ground layer may be located between the set of stub regions and the signal layer. The method may include drilling to remove at least a portion of a stub region of a via of the set of vias. The method may include performing an electrical test to determine whether a sliver of conductive material is included within the via after drilling to remove the at least a portion of the stub region of the via.

The present invention provides a method for detecting and adjusting failed back-drills in PCBs in the process of fabricating a PCB so that the failed back-drill can be screened out or repaired. This is accomplished, by after detecting poor back drills in a PCB, measuring the actual thickness of each PCB board. Next, the measured actual thickness of each PCB board is compared with .the theoretical thickness of each PCB board. The back drill depth for each area of the PCB board is then adjusted for its theoretical thickness and percent variation from the measured thickness.to adjust the poor back drill.

An electromagnetic wave transmission board proofed against internal signal leakage includes an inner plate, a first outer plate, a second outer plate, a first plate bump, a first conductive bump, a second plate bump, and a second conductive bump. The inner plate defines a first through hole with a plated metal layer on the hole wall. The first and second plated bumps are disposed between the first outer and inner plates. The second plate bump and the second conductive bump are disposed between the second outer plate and the inner plate. The plate metal layer, the first plate bump, the first conductive bump, the first outer plate, the second outer plate, the second conductive bump, and the second plated bump jointly form an air-filled chamber. A method for manufacturing the electromagnetic wave transmission board is also provided.

Embodiments of the disclosure provide a via structure, a method for preparing the same and a method for regulating impedance of a via structure. The via structure includes a first via, a second via and a first connecting through hole; and a first metal layer a the second metal layer. The first connecting through hole is located between the first via and the second via, and covers part of the first via and part of the second via. The first metal layer and the second metal layer are respectively located in the first via and the second via. The first metal layer and the second metal layer respectively cover a sidewall of the first via and a sidewall of the second via. The first metal layer is separated from the second metal layer through the first connecting through hole.

The present disclosure relates to systems and methods using thermal vias to increase the current-carrying capacity of conductive traces on a multilayered printed circuit board (PCB). In various embodiments, parameters associated with vias may be selected to control various electrical and thermal properties of the conductive trace. Such parameters include the via diameter, a plating thickness, a number of vias, a placement of the vias, an amount of conductive material to be added or removed from the conductive trace, a change in the resistance of the conductive trace, a change in a fusing measurement of the conductive trace, and the like.

A semiconductor package according to an embodiment includes a first insulating layer including a through hole; an insulating member disposed in the through hole of the first insulating layer; a first electrode layer disposed on the insulating member; a second insulating layer disposed on the first electrode layer; and a first through electrode passing through the second insulating layer, wherein the first through electrode overlaps the first electrode layer and the insulating member in a vertical direction.

A rigid-flex board is manufactured by attaching multiple self-adhesive copper foil films to a flexible circuit board through multiple build-up processes, thereby eliminating the need to pre-fabricate a rigid board and slot the rigid board. The build-up processes of the self-adhesive copper foil films allow the resulting rigid boards to be highly uniform in thickness so that thickness deviation of the rigid-flex board can be reduced.

The present disclosure discloses a multilayer circuit board comprising a plurality of metal layers, a blind via and/or a buried via, the multilayer circuit board is capable of transmitting signal between the different metal layers. The blind via has a pad on a non-opening side of the blind via. An upper or lower layer metal layer on the non-opening side of the blind via adjacent to the blind via has a first hole which is located in a position corresponding to the pad on the non-opening side of the blind via in a depth direction of the blind via; and/or an upper and/or lower layer adjacent to the buried via has a second hole which is located in a position corresponding to the pad of an upper and/or lower orifice of the buried via in a depth direction of the buried via.