Patent ID: 8878078

Claim:
A printed wiring board, comprising: an interlayer resin insulating layer provided on a substrate; a first via hole formed in the interlayer resin insulating layer and having a via conductor layer therein; a second via hole formed in the interlayer resin insulating layer and having a via conductor layer therein; a conductor circuit provided on the interlayer resin insulating layer; a solder resist layer provided on the conductor circuit, the via conductor layers and on the interlayer resin insulating layer, the solder resist layer having an opening which exposes only an exposed portion of the conductor circuit, and another opening which exposes an exposed portion of the via conductor; a single metal layer of tin provided on and in direct contact with said exposed portion of the conductor circuit, and a conductive adhesive provided on and in direct contact with the single metal layer and configured to adhere the single metal layer to an electrode of an integrated circuit to be connected to the printed wiring board; and another single metal layer of tin provided in direct contact with said exposed portion of the via conductor, and a conductive adhesive provided on and in direct contact with the another single metal layer and configured to adhere the single metal layer to another electrode of the integrated circuit to be connected to the printed wiring board.