METHOD OF FABRICATING SOLDER FOR CORELESS PACKAGE SUBSTRATE

摘要

A method for forming a solder is provided to form a high reliable solder with a low cost by not using a feeding process and a pad process for an electrolytic plating process, and a metal sputtering process. A copper foil is coated in a side of an insulating layer of a CCL(Copper Cladded Layer) by performing a copper plating on the overall surface of the CCL. A solder(506') is formed by performing a solder plating and exposing a copper foil selectively by patterning and forming a dry film(545) formed on the surface of the CCL. A first insulating layer(510) and the copper foil are aligned and stacked on the CCL peeling off the dry film. A copper foil circuit electrically connected to the solder is formed on the external surface(535) by selectively opening the first insulating layer stacked with the solder and performing the copper plating. A protective layer is coated on the upper layer and the lower layer and the copper foil coated on a side surface of the CCL layer is removed by performing the alkali etching. Two substrates stacked in the upper and lower parts of the CCL are separated from the CCL by peeling off the CCL by pressurizing the side of the substrate. The solder is completed by IR reflowing the exposed solder in the separated substrate.