Patent ID: 8536696

Claim:
A package structure, comprising: a core substrate comprising: a resin insulating substrate having a first side and a second side opposing the first side, a first conductive layer formed on said first side of the resin insulating substrate, a second conductive layer on said second side of the resin insulating substrate, and a through hole conductor connecting the first conductive layer to the second conductive layer; a first build up structure formed on the first side of the resin insulating substrate, the first build up structure comprising a first interlayer resin insulating layer and a first conductor layer; a second build up structure comprising: a plurality of interlayer resin insulating layers formed on the second side of the resin insulating substrate and including a second interlayer resin insulating layer and an outermost interlayer resin insulating layer, and a second conductor layer comprising a plurality of conductor circuits formed on the second interlayer resin insulating layer and below the outermost interlayer resin insulating layer; a pad structure formed on the outermost interlayer resin insulating layer; a solder resist formed on the outermost interlayer resin insulating layer and the pad structure, the solder resist comprising an organic resin and having an opening exposing a partially exposed portion of the pad structure; a conductive connecting pin configured to establish an electrical connection with another substrate, the conductive connecting pin being secured to the partially exposed portion of the pad structure via a solder; and a via hole formed through the outermost interlayer resin insulating layer directly below the pad structure and electrically connecting the pad structure and at least one of the conductor circuits of the second conductor layer formed below the outermost interlayer resin insulating layer.