Package substrate manufactured using electrolytic leadless plating process, and method for manufacturing the same

Abstract

A package substrate of, for example, a BGA type or a CSP type, manufactured by carrying out an electrolytic Au plating process without using any plating lead line for formation of bond fingers and solder ball pads, and a method for manufacturing the package substrate. The method includes the steps of laminating first dry films over upper and lower surfaces of a base substrate having via holes while being formed at its upper and lower surfaces with copper foils, and patterning the first dry films to expose predetermined surface portions of the base substrate, removing portions of the copper foils not covered by the first dry films to form circuits, stripping the first dry films, and forming a plated layer over the base substrate, laminating second dry films over the plated surfaces of the base substrate, and patterning the second dry films to expose portions of the plated surfaces of the base substrate corresponding to regions where Au is to be plated, removing the plated layer from the exposed surface portions of the base substrate corresponding to the Au plating regions, plating Au on the exposed surface portions of the base substrate, stripping the second dry films, and removing the remaining plated layer to expose the circuits, and coating a solder resist on the exposed circuits while exposing predetermined portions of the circuits.

Dependencies are inferred from the claim text.