METHOD OF MANUFACTURING MULTILAYER WIRING BOARD

PROBLEM TO BE SOLVED: To provide a method of manufacturing a multilayer wiring board in which a conductor layer can be uniformly formed on an external insulating layer by electrolytic plating with good operability without causing a defect such as a flaw. SOLUTION: When the external insulating layer 30 is laminated on at least one surface of an internal layer circuit board 10, the end of the internal layer circuit board is extended out beyond the edge of an external insulating layer, an exposed conductor portion 20 is formed at the extended end, and one or more vias 47 reaching the conductor wiring circuit pattern of the internal layer circuit board are formed in an external layer substrate 55', a conductive layer 52 connected to the conductor wiring circuit pattern of the internal layer circuit board is formed on the internal surface of the via, and a feeding conductor layer 52A connecting the exposed conductor portion or conductor wiring electrically connected to the exposed conductor portion to an external layer board surface is formed. Electric power is fed from the exposed conductor portion of the feeding internal layer circuit board through the conductor layer for electric power feeding, and the via internal surface and the surface of the external layer substrate are subjected to electrolytic plating. COPYRIGHT: (C)2009,JPO&INPIT