Patent ID: 7918020

Claim:
A method for manufacturing an electroconductive material-filled throughhole substrate of which the front side and back side have been electrically conducted to each other through an electroconductive material filled into the throughholes comprising the steps of: forming an electroconductive base layer on one side of a core substrate having throughholes, wherein the electroconductive base layer has an opening corresponding to the throughholes; and filling the throughholes with an electroconductive material by electroplating using the electroconductive base layer as a seed layer; wherein the electroconductive material is precipitated on the electroconductive base layer and further, the electroconductive material is precipitated in the openings to clog the openings at a clog site, and then the electroconductive material is precipitated and grown from the clog site toward the inside of the throughholes to fill the electroconductive material into the throughholes.