Patent ID: 8785786

Claim:
A wiring board comprising: a conductor layer; a solder resist layer comprised of thermosetting resin and laminated on the conductor layer, the solder resist layer defining a through-hole extending through the solder resist layer such that a portion of the conductor layer is located below the through-hole; and a conductor post comprised of tin, copper, or a solder that is electrically connected to the portion of the conductor layer below the through-hole, the conductor post including a lower conductor post and an upper conductor post located above the lower conductor post; wherein the lower conductor post is located within the through-hole and includes an external side surface with an external alloy layer comprised of copper and tin, and a lower end surface with a lower end alloy layer comprised of copper and tin; and wherein the upper conductor post projects outside the solder resist layer and at least a part of a lower end surface of the upper conductor post is brought into intimate contact with an outer surface of the solder resist layer.