A printed circuit board includes: a first substrate including a first cavity and first circuit units; and a second substrate disposed in the first cavity of the first substrate with an electronic component disposed therein, and including second circuit units having a higher density than the first circuit units, wherein the second substrate includes a first region and a second region, the first region of the second substrate includes an outermost circuit layer among the second circuit units, and circuit layers in the first region of the second substrate have a higher density than circuit layers in the second region of the second substrate.

A flexible circuit board and a manufacturing method thereof are provided. The flexible circuit board includes a circuit structure, a first cover layer, and a second cover layer. The circuit structure has a top surface and a bottom surface opposite to the top surface. The circuit structure includes multiple circuit layers and multiple insulating layers stacked alternately. A material of the insulating layers is a photosensitive dielectric material and a Young's modulus of the insulating layers is between 0.36 GPa and 8 GPa. The first cover layer is disposed on the top surface of the circuit structure. The second cover layer is disposed on the bottom surface of the circuit structure.

A printed circuit board includes a plurality of layers including attachment layers and routing layers; and via patterns formed in the plurality of layers, each of the via patterns including first and second signal vias forming a differential signal pair, the first and second signal vias extending through at least the attachment layers; ground vias extending through at least the attachment layers, the ground vias including ground conductors; and shadow vias located adjacent to each of the first and second signal vias, wherein the shadow vias are free of conductive material in the attachment layers. The printed circuit board may further include slot vias extending through the attachment layers and located between via patterns.

In one embodiment, the substrate is configured for a semiconductor laser diode and comprises a plurality of substrate layers. The substrate layers include insulating layers and carrier layers, which are thicker. A plurality of electrical contact surfaces, which are configured for the semiconductor laser diode, a laser capacitor and a control chip, are located on an assembling side of a first, uppermost substrate layer, which is an insulating layer. Electrical conductor tracks, which electrically interconnect the contact surfaces, are located on the one hand between the first insulating layer and a second insulating layer, and on the other hand between the second insulating layer and a third substrate layer, which is preferably an insulating layer.

A multilayer board includes a flexible substrate including insulating layers stacked and a pair of through-holes penetrating the insulating layers, and an interlayer connecting conductor in an opposing region in which the pair of through-holes opposes each other in a plan view of the insulating layers viewed from a stacking direction. A cross section of the flexible substrate taken in a lateral direction passing through the pair of through-holes and the interlayer connecting conductor and the stacking direction has a U or S shape. In the cross section, a curvature radius of an inner region located between the pair of through-holes is larger than a curvature radius of an outer region adjacent to the pair of through-holes on an outer side thereof.

A component carrier includes a stack with at least one electrically conductive layer structure and at least one electrically insulating layer structure, a component embedded in the stack, and a via formed in the at least one electrically insulating layer structure along a horizontal path having a length being larger than a horizontal width.

Systems and methods for applying solder to a pin. The methods comprising: disposing a given amount of solder on a non-wetable surface of a planar substrate; aligning the pin with the solder disposed on the non-wetable surface of the planar substrate; inserting the pin in the solder; and performing a reflow process to cause the solder to transfer from the planar substrate to the pin.

A printed circuit board which improves the peel strength of a wiring pattern formed at a cavity bottom portion while enabling connection between an electronic component inside a cavity and a circuit outside the cavity to be performed at the cavity bottom portion, includes a cavity in a partial region of a multilayer substrate laminated with an insulating resin layer and an electrical conductor layer on a bottom layer of an insulating resin substrate. The cavity opens on a side of the insulating resin substrate, penetrates the insulating resin substrate, and includes a surface of the insulating resin layer as a bottom surface. The electrical conductor layer has a surface, the surface having a height equivalent to a height of the surface of the insulating resin layer and being embedded in the insulating resin layer in a manner to form a portion of the bottom surface.

A wiring substrate includes a first conductor layer, an insulating layer formed on the first conductor layer, a second conductor layer formed on the insulating layer, a connection conductor penetrating through the insulating layer and connecting the first and second conductor layers, and a coating film formed on a surface of the first conductor layer and adhering the first conductor layer and the insulating layer. The first conductor layer includes a conductor pad in contact with the connection conductor such that the conductor pad has a surface having a first region and a second region on second conductor layer side and that surface roughness of the first region is different from surface roughness of the second region, and the conductor pad of the first conductor layer is formed such that the first region is covered by the coating film and that the second region is covered by the connection conductor.

A printed circuit board includes a first insulating layer; a first wiring layer having at least a portion buried in one surface side of the first insulating layer and having at least a portion of one surface exposed from the one surface of the first insulating layer; a metal post disposed on the exposed one surface of at least the portion of the first wiring layer; and a second wiring layer disposed on the other surface of the first insulating layer. A width of a first surface, connected to the exposed one surface of at least a portion of the first wiring layer, of the metal post, is greater than a width of a second surface of the metal post opposing the first surface.