Patent ID: 9713267
Date: 2017-07-18
CPC Classifications: H05K,Y02P,Y10T

Claim:
1. A method for manufacturing a printed wiring board, comprising: forming a first conductive layer on a first metallic foil provided on a carrier such that the first conductive layer includes a mounting pattern positioned to connect an electronic component via a plurality of conductive posts; forming on the first metallic foil a laminate structure comprising a resin insulating layer and a second metallic foil such that the first conductive layer is embedded into a surface of the resin insulating layer; forming a hole for a via conductor through the laminate structure such that the hole exposes the first conductive layer; removing the carrier from the first metallic foil such that the first metallic foil is exposed; forming a metal film on the laminate structure and the first metallic film such that the metal film is formed on the first metallic foil, on the second metallic foil and inside the hole; forming a plating resist film on the metal film such that the plating resist film has a pattern exposing portion of the metal film substantially corresponding to the mounting pattern, the hole and portion of the second metallic foil for forming a second conductive layer on the resin insulating film; applying electroplating on the portion of the metal film exposed by the pattern of the plating resist film such that an electroplating conductive layer is formed on the portion of the metal film not covered by the plating resist film; removing the plating resist film from the metal film such that portion of the metal film below the plating resist film are exposed; and applying etching removal on the portion of the metal film exposed by the removing of the plating resist film such that portion of the first metallic foil and second metallic foil below the portion of the metal film exposed by the removing of the plating resist film is removed and that the plurality of conductive posts protruding from the surface of the resin insulating layer is formed on the mounting pattern, wherein the applying of etching removal comprises applying of etching removal such that the surface of the mounting pattern of the first conductive layer has portions being in contact with the conductive posts and portions not being in contact with the conductive posts and recessed with respect to the portions being in contact with the conductive posts and the surface of the resin insulating layer, each of the conductive posts has a three layer structure comprising a metal layer formed on the first conductive layer, a first metal film formed on the metal layer, and a second metal film formed on the first metal film, the first conductive layer comprises an electroplating film, the metal layer is one of a copper foil and a nickel foil, the first metal film is one of an electroless plating film and a sputter film, and the second metal film is an electroplating film formed such that the electroplating film has a thickness which is greater than a thickness of the metal layer and a thickness of the first metal film.