Patent ID: 8866025

Claim:
A multilayer wiring board comprising: a build-up layer including a conductor layer and a resin insulation layer that are alternately layered; a conductive pad formed so as to project from a surface of the resin insulation layer and having an upper surface, the upper surface having an outer periphery portion and a center portion recessed relative to the outer periphery portion; a solder layer formed on the conductive pad so that the solder layer over the upper surface of the conductive pad is situated above a level defined by the outer periphery portion; and a barrier metal layer formed between the conductive pad and the solder layer so as to cover the entire conductive pad; wherein: the solder layer covers the conductive pad and the barrier metal layer that covers the conductive pad in its entirety; and a coating thickness of the barrier metal layer formed on a side end face of the conductive pad situated on the resin insulation layer is made greater than a coating thickness of the barrier metal layer formed on the surface of the conductive pad situated at a higher position than the side end face.