SHIELDED SIGNAL VIAS IN PRINTED CIRCUIT BOARDS FOR HIGH-FREQUENCY AND BROADBAND SIGNALS

A printed circuit board (PCB) core structure is provided for the transition of signals from one side of a PCB to an opposing side of the PCB. The PCB core structure may include a laminated core including an inner core including a plurality of conductive layers (N layers), a first dielectric layer, a first conductive trace disposed over the Nth conductive layer on a first side of the laminated core. The PCB core structure may also include a signal via extending from a first conductive layer to an Nth conductive layer through the laminated core, the signal via configured to connect the first conductive trace to a pin or a second conductive trace on a second side of the laminated core. The PCB core structure may also include a shielding structure surrounding the signal via and partially extending from the first conductive layer to the Nth conductive layer. The PCB core structure may also include a cavity removing a portion of the shielding structure in the Nth conductive layer and filled with a dielectric material. The cavity filled with the dielectric material prevents the first conductive trace from shorting to the shielding structure. The PCB core structure may be fabricated by using a single-lamination cycle.