Patent ID: 8692129

Claim:
A printed wiring board, comprising: an interlayer insulation layer; a plurality of first pads positioned to mount a semiconductor element and forming a first pad group on the interlayer insulation layer; a plurality of second pads forming a second pad group on the interlayer insulation layer and positioned along a peripheral portion of the first pad group; a first solder-resist layer formed on the interlayer insulation layer and having a plurality of first opening portions exposing portions of the first pads, respectively, and a plurality of second opening portions exposing portions of the second pads, respectively; a plurality of conductive posts formed on the plurality of second pads through the plurality of second opening portions of the first solder-resist layer, respectively; and a second solder-resist layer formed on the first solder-resist layer and having a third opening portion exposing the plurality of first pads and a plurality of fourth opening portions exposing surface portions of the conductive posts, respectively, wherein the plurality of second opening portions has a diameter which is set greater than a diameter of the plurality of conductive posts, and the second solder-resist layer is filling gaps formed between the second opening portions and the conductive posts.