Patent ID: 7795542

Claim:
A multi-layer printed circuit board comprising: a core substrate having a plurality of penetrating holes and having a first surface and a second surface; a plurality of buildup layers over the first and second surfaces of the core substrate, respectively, each of the buildup layers comprising a plurality of interlayer resin insulating layers and a plurality of conductor layers alternately provided, the plurality of interlayer resin insulating layers including a lower interlayer resin insulating layer formed adjacent to the core substrate; a plurality of through holes formed in the plurality of penetrating holes of the core substrate, respectively, and through the lower interlayer resin insulating layers and filled with a resin filler including inorganic particles; a plurality of via holes filled with a resin filler including inorganic particles and formed in the lower interlayer resin insulating layers; and a plurality of vias holes formed over the plurality of vias holes in the lower interlayer resin insulating layers, respectively, wherein the conductor layers include ones formed to cover exposed surfaces of the resin filler filled in the via holes in the lower interlayer resin insulating layers, and the via holes are formed right on the via holes in the lower interlayer resin insulating layers through the ones of the conductive layers, respectively.