Patent ID: 7303978

Claim:
A method of fabricating a board for mounting a semiconductor chip thereon, said method comprising the steps of: forming an etching resist pattern at a portion that corresponds to a position for an electrode pad on one surface of a matrix sheet which is a metal plate; etching said one surface of said metal plate to make the portion of said metal plate, which is covered by said etching resist pattern, convex shape; peeling and removing said etching resist pattern; forming a plating resist on said one surface of said metal plate, said plating resist having an opening which has a smaller diameter than the diameter of said convex-shaped portion at a portion that corresponds to a position for the electrode pad; etching an exposed portion of said metal plate through said opening of said plating resist to make a recessed portion on a surface of said convex-shaped portion; forming an electroplating layer at said recessed portion to form the electrode pad which protrudes from said surface of said convex-shaped portion; peeling and removing said plating resist; forming an insulating layer of insulating resin on said surface of said metal plate on which said electrode pad is formed, by a single process using a single material; forming a via hole in said insulating layer; forming a via in said via hole in said insulating layer by plating; forming a conductive layer by plating on a surface of said insulating layer remote from said metal plate, said conductive layer being connected to said electrode pad through said via; and removing said metal plate by etching, wherein a pattern of recess and land is transferred from said surface of said metal plate to a surface of said insulating layer in order to form a recess on said insulating layer and to position said electrode pad in said recess so that the outer periphery of said electrode pad is located away from the inner periphery of said recess and a surface of said electrode pad is positioned between a bottom surface of said recess and said surface of said insulating layer.