Package substrate

Abstract

This disclosure provides a package substrate and its fabrication method. The package substrate includes: a carrier; a first wiring layer formed on the carrier; a conductive pillar layer having a plurality of metal pillars on the first wiring layer; a molding compound layer formed on the first wiring layer, covering all the first wiring layer and the metal pillars, and exposing one end face of each metal pillar; a second wiring layer formed on the molding compound layer and the exposed end faces of the metal pillars; and a protection layer formed on the second wiring layer.

What is claimed is: 
     
         1 . A package substrate comprising:
 a carrier;   a first wiring layer formed on the carrier;   a conductive pillar layer having a plurality of metal pillars on the first wiring layer;   a molding compound layer formed on the first wiring layer, covering all the first wiring layer and the metal pillars, and exposing one end face of each metal pillar;   a second wiring layer formed on the molding compound layer and the exposed end faces of the metal pillars; and   a protection layer formed on the second wiring layer.   
     
     
         2 . The package substrate according to  claim 1 , wherein the package substrate is a flip-chip chip size package (FCCSP) substrate. 
     
     
         3 . The package substrate according to  claim 1 , wherein the first wiring layer comprises at least one metal wire. 
     
     
         4 . The package substrate according to  claim 1 , wherein the second wiring layer comprises at least one metal wire. 
     
     
         5 . The package substrate according to  claim 1 , wherein the metal pillars comprise copper pillars. 
     
     
         6 . The package substrate according to  claim 1 , wherein the molding compound layer is formed of a material selected from the group consisting of novolac-based resin, epoxy-based resin, and silicone-based resin.