STRUCTURE OF A HIGH-DENSITY PACKAGE SUBSTRATE AND A FABRICATION METHOD THEREOF CAPABLE OF IMPROVING A DEGREE OF CIRCUIT INTEGRATION

摘要

PURPOSE: A structure of a high-density package substrate and a method for fabricating thereof are provided to perform gold-plating using a base copper foil as a lead line, thereby improving a degree of freedom in circuit design.;CONSTITUTION: A fabrication method of a printed circuit board comprises the steps of: forming a base copper foil (20) on top and bottom surfaces of a dummy; forming a carrier copper foil (30) on the base copper foil; applying a dry film to the surface of the carrier copper foil and transferring a circuit pattern to form a plating mask; copper-plating the dry film to form a first copper circuit and removing the dry film; laminating successively an insulation layer (60) and a second copper foil (70) on the first copper circuit; making a via hole to electrically connects the second copper foil and the first copper circuit; copper-plating to fill the via hole and form an outer copper foil and transferring a circuit pattern on the outer copper foil to form a second copper circuit; applying a solder resist on the surface of the second copper circuit; peeling off the dummy to divide a result of the previous step into two structures; and exposing a selected portion of copper surface of the second copper circuit by opening the solder resist and then gold-plating without making a lead line.;COPYRIGHT KIPO 2013