Multilayer wiring board

摘要

A multilayer wiring board including a build-up layer comprising a conductor layer and a resin insulation layer that are alternately layered, conductive pads formed on a surface of a resin insulation layer so as to project from the surface, and a solder layer formed over an upper surface of each of the conductive pads is provided. The upper surface of the conductive pads may have a recess, and the entire surface of the solder layer may be situated at an elevated position with respect to an outer periphery portion of the upper surface.

主权项

1. 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; anda 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.