Patent 7886438 was granted and assigned to Fujikura on February, 2011 by the United States Patent and Trademark Office.
At least one base material having a wiring circuit that has been formed into a predetermined outer shape is bonded to a motherboard. The motherboard wiring board and the base material having a wiring circuit are electrically connected to each other at least one portion through an inner via hole. The outer shape of the base material having a wiring circuit is smaller than the outer shape of the motherboard, with the base material having a wiring circuit having an island shape on the motherboard.