Realized is a multilayer substrate and a multilayer substrate array, each of which has a high degree of freedom in a production method. At least part of an outer periphery (51) of a multilayer substrate (100), which includes a wiring provided on an inner layer, is processed so as to have a wave shape.

A transmission line substrate includes a line portion and a connecting portion. The transmission line substrate includes a base material, a first ground conductor, a second ground conductor, a signal line, an external electrode, a second interlayer connection conductor. In the line portion, a transmission line having a strip line structure including the signal line, the first ground conductor, and the second ground conductor is provided. In the connecting portion, the signal line and the external electrode face each other in a stacking direction, without including therebetween an interlayer connection conductor. The second interlayer connection conductor surrounds a facing portion in which the signal line and the external electrode face each other in the Z-axis direction.

Provided is a printed circuit board which includes: a first dielectric layer including a first principal surface and a second principal surface on a side opposite to the first principal surface; a first adhesive layer formed on the first principal surface; a first metal foil pattern formed on the first adhesive layer and forming a signal line; and a second metal foil pattern formed on the second principal surface and forming a ground layer, in which the first metal foil pattern has a higher specific conductivity than a specific conductivity of the second metal foil pattern.

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.

An interconnection for flex circuit boards used, for instance, in a quantum computing system are provided. In one example, the interconnection can include a first flex circuit board having a first side and a second side opposite the first side. The interconnection can include a second flex circuit board having a third side and a fourth side opposite the third side. The first flex circuit board and the second flex circuit board are physically coupled together in an overlap joint in which a portion of the second side for the first flex circuit board overlaps a portion of the third side of the flex circuit board. The interconnection can include a signal pad structure positioned in the overlap joint that electrically couples a first via in the first flex circuit board and a second via in the second flex circuit board.

A flexible flat cable according to various embodiments of the disclosure may include a first insulation layer having a plate shape, a first conductive pattern disposed on the first insulation layer, a second conductive pattern disposed on the first insulation layer to be spaced apart from the first conductive pattern at a predetermined interval, a second insulation layer covering at least a portion of the first conductive pattern and disposed on the first insulation layer to cover the first conductive pattern, a first shield member including a first shield layer disposed on the first insulation layer and the second insulation layer to cover the first conductive pattern and the second conductive pattern, and a second shield layer disposed on the first shield layer to cover the first shield layer, and a third insulation layer surrounding the first shield layer such that at least a portion of the first shield layer of the first shield member, which is exposed between the first insulation layer and the second shield layer of the first shield member is covered.

A circuit board structure includes a substrate, a third dielectric layer, a fourth dielectric layer, a first external circuit layer, a second external circuit layer, a conductive through hole, a first annular retaining wall, and a second annular retaining wall. The conductive through hole penetrates through the third dielectric layer, a second dielectric layer, and the fourth dielectric layer. The conductive through hole is electrically connected to the first external circuit layer and the second external circuit layer. The first annular retaining wall is disposed in the third dielectric layer, surrounds the conductive through hole, and is electrically connected to the first external circuit layer and the first inner circuit layer. The second annular retaining wall is disposed in the fourth dielectric layer, surrounds the conductive through hole, and connects to the second external circuit layer and the second inner circuit layer electrically.

An electronic substrate includes a dielectric core, a first conducting layer on a first side of the core and a second conducting layer on the second side of the core opposite the first side. At least one differential coaxial through-via includes a first inner signal through-via that is at least electrical conductor lined for a first signal path and at least a second inner signal through-via that is also at least electrical conductor lined positioned side-by-side and being dielectrically isolated from the first inner signal through-via for a second signal path. An annular-shaped outer ground shield enclosure is at least conductor lined that surrounds and is dielectrically isolated from both the first and second inner signal through-vias.

An electronic substrate includes a dielectric core, a first conducting layer on a first side of the core and a second conducting layer on the second side of the core opposite the first side. At least one differential coaxial through-via includes a first inner signal through-via that is at least electrical conductor lined for a first signal path and at least a second inner signal through-via that is also at least electrical conductor lined positioned side-by-side and being dielectrically isolated from the first inner signal through-via for a second signal path. An annular-shaped outer ground shield enclosure is at least conductor lined that surrounds and is dielectrically isolated from both the first and second inner signal through-vias.

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.