Patent ID: 8230592

Claim:
A method comprising the steps of: providing a substrate having a plurality of insulator layers and one or more internal conductive traces, wherein a first through-hole extends completely through the substrate from a first surface of the substrate to a second surface of the substrate, and wherein the first through-hole passes through a first one of the one or more internal conductive traces; providing a first plated-through-hole (PTH) plug in the first through-hole, wherein the first PTH plug extends from a second end thereof at or adjacent to the substrate's second surface to a first end thereof at or adjacent to the first internal conductive trace; providing a seed photoresist on portions of the substrate's first and second surfaces, wherein the seed photoresist has open regions in the vicinity of the first through-hole, and wherein the open regions of the seed photoresist expose a portion of the substrate's first surface adjacent the first through-hole, a portion of the first through-hole extending from the substrate's first surface to the first internal conductive trace, the first end of the first PTH plug, and the second end of the first PTH plug; applying seed material to the seed photoresist, the exposed portion of the substrate's first surface, the exposed portion of the first through-hole, the exposed first end of the first PTH plug, and the exposed second end of the first PTH plug; stripping the first PTH plug and the seed photoresist so that the seed material remains substantially only at a portion of the substrate's first surface adjacent the first through-hole and at a portion of the first through-hole extending from the substrate's first surface to the first internal conductive trace; plating a first conductive via plating onto the first through-hole so that the first conductive via plating extends from the substrate's first surface to and terminates substantially at the first internal conductive trace.