A co-axial structure includes a substrate, a first conductive structure, a second conductive structure, and an insulating layer. The substrate includes a first surface. The first conductive structure includes a first circuit deposited on the first surface and a first via penetrating the substrate. The second conductive structure includes a second circuit deposited on the first surface and a second via penetrating the substrate. The first via and the second via extend along a first direction. The first circuit and the second circuit extend along a second direction, and the second direction is perpendicular to the first direction. The insulating layer is located between the first via and the second via. The first conductive structure and the second conductive structure are electrically insulated. The first circuit and the second circuit are coplanar.

A co-axial structure includes a substrate, a first conductive structure, a second conductive structure, and an insulating layer. The substrate includes a first surface. The first conductive structure includes a first circuit deposited on the first surface and a first via penetrating the substrate. The second conductive structure includes a second circuit deposited on the first surface and a second via penetrating the substrate. The first via and the second via extend along a first direction. The first circuit and the second circuit extend along a second direction, and the second direction is perpendicular to the first direction. The insulating layer is located between the first via and the second via. The insulating layer includes a filler. The first conductive structure and the second conductive structure are electrically insulated. The first circuit and the second circuit are coplanar.

A transmission line includes a first structure including a first flexible resin base material, and a first ground conductor thereon, a second structure including a second flexible resin base material, and a first signal line and an interlayer connection conductor in or on the second resin base material, a first spacer between the first and second structures, and a first metal joining material joining the first and second structures with the first spacer interposed therebetween. A first hollow portion is between the first and second structures with the first spacer interposed therebetween. The first signal line and the first ground conductor face each other in a joining direction with the first hollow portion interposed therebetween. The first resin base material and the second resin base material are not in contact with each other. The first metal joining material has a melting point lower than that of the interlayer connection conductor.

A circuit board includes a first external circuit layer, a first substrate, a second substrate, a third substrate, and a conductive through hole structure. The first substrate includes conductive pillars electrically connecting the first external circuit layer and the second substrate. The second substrate has an opening and includes a first dielectric layer. The opening penetrates the second substrate, and the first dielectric layer fills the opening. The third substrate includes an insulating layer, a second external circuit layer, and conductive holes. A conductive material layer of the conductive through hole structure covers an inner wall of a through hole and electrically connects the first and the second external circuit layers to define a signal path. The first external circuit layer, the conductive pillars, the second substrate, the conductive holes and the second external circuit layer are electrically connected to define a ground path surrounding the signal path.

Provided is a circuit board, including a first substrate, a second substrate, a third substrate, a fourth substrate, multiple conductive structures, and a conductive via structure. The second substrate is disposed between the first substrate and the third substrate. The third substrate is disposed between the second substrate and the fourth substrate. The third substrate has an opening penetrating the third substrate and includes a first dielectric layer filling the opening. The conductive via structure penetrates the first substrate, the second substrate, the first dielectric layer of the third substrate, and the fourth substrate, and is electrically connected to the first substrate and the fourth substrate to define a signal path. The first substrate, the second substrate, the third substrate and the fourth substrate are electrically connected through the conductive structures to define a ground path, and the ground path surrounds the signal path.

In some embodiments, an apparatus can include a printed circuit board (PCB) that has layers and includes a first portion and a second portion. The first portion can have a data port and a power port. A first layer is associated with data of the first portion of the PCB, and a second layer is associated with power of the first portion of the PCB. The second portion can have a data port and a power port. A third layer is associated with data of the second portion, and a fourth layer is associated with power of the second portion. The first portion or the second portion can have vias defining an electromagnetic interference (EMI) shield. The apparatus can include a power filter and a data filter that can, respectively, isolate power and data of the first portion from the second portion.

A method for manufacturing a flexible circuit board capable of transmitting high frequency signals with reduced attenuation includes providing an inner wiring board including a first conductive wiring layer and a first substrate layer, the first conductive wiring layer including a signal line and two ground lines on both sides of the signal line, the first substrate layer covering a side of the first conductive wiring layer and defining first through holes which expose the signal line; providing two copper clad laminates including a second substrate layer and a copper foil, the second substrate layer having second through hole aligned with the first through holes; laminating the two copper clad laminates onto two sides of the inner wiring board via two adhesive layers, each adhesive layer defining third through holes aligned with the first and second through holes; and forming a second conductive wiring layer from the copper foil.

A printed circuit board includes a connector insertion area including many rows of crimping holes, each row of crimping holes includes at least two pairs of signal crimping holes (SCHs), and each pair of SCHs includes two SCHs. In a row arrangement direction of the crimping holes, at least one ground crimping hole (GCH) is arranged on either side of each pair of SCHs. A depth of the GCH is greater than or equal to a depth of the SCH, the GCH includes a main hole and a shielding component on at least one side of the main hole, a part of a side wall of the main hole is a part of a side wall of the shielding component, and a sum of lengths of the main hole and the shielding component in a first direction is greater than a length of the SCHs in the first direction.

A printed circuit board, includes: a first insulating layer on which a wiring line is disposed; a second insulating layer covering an upper portion of the wiring line; a first conductive shield wall spaced apart from two opposing sides of the wiring line in a width direction of the wiring line, and extending in a length direction of the wiring line; and a second conductive shield wall spaced apart from two opposing ends of the first conductive shield wall in the length direction, and extending the a width direction. At least one of the first conductive shield wall or the second conductive shield wall includes a plurality of via walls each extending in a thickness direction of the first insulating layer and the second insulating layer and having a gap is disposed therebetween.

Certain aspects of the present disclosure generally relate to a circuit board with ground vias offset from associated ground bumps. One example circuit board generally includes a first signal connection terminal configured to connect a signal line of the circuit board to an integrated circuit (IC); a ground plane having a first ground connection terminal disposed adjacent to the first signal connection terminal, the first ground connection terminal being configured to provide a ground connection between the ground plane and the IC; and a first ground via associated with and disposed adjacent to the first ground connection terminal and coupled to the ground plane, wherein, from an overhead view of the circuit board, the first ground via is located at a position that is offset from a first axis on which the first signal connection terminal and the first ground connection terminal are disposed.