Patent ID: 9648759
Date: 2017-05-09
CPC Classifications: H05K

Claim:
1. A multilayer wiring board comprising: a laminate formed by integrally laminating an inner layer material with an inner layer wiring pattern formed thereon, an insulating layer, and a metal foil for an upper layer wiring pattern; a hole for interlayer connection penetrating the metal foil for an upper layer wiring pattern and the insulating layer of the laminate; an overhang of the metal foil for an upper layer wiring pattern formed at an opening of the hole for interlayer connection; lower space formed between the overhang of the metal foil and an inside wall of the hole for interlayer connection; and interlayer connection in which the hole for interlayer connection is filled with electrolytic filling plating layers, wherein the electrolytic filling plating layers that fill the hole for interlayer connection are formed as at least two or more layers, wherein the lower space between the overhang of the metal foil for an upper layer wiring pattern formed at the opening of the hole for interlayer connection and the inside wall of the hole for interlayer connection is filled with any electrolytic filling plating layer except for an outermost layer of the two or more layers of electrolytic filling plating layers, and a maximum diameter in the inside of the interlayer connection formed by any electrolytic filling plating layer except for an outermost layer is equal to or larger than a minimum diameter of the opening.