CONTACT HIGH DENSITY TYPE BALL GRID ARRAY PACKAGE FOR FLIP CHIP

摘要

PROBLEM TO BE SOLVED: To obtain a flip chip ball grid array package which has a smaller size than the conventional package has. SOLUTION: A plurality of conductive contacts 20 are arranged on the upper surface of a substrate 10 so as to electrically connect a semiconductor device mounted on the substrate 10 to the substrate 10. A plurality of through holes 14 is formed through the substrate 10 from the upper surface to the lower surface so as to electrically connect all layers in the substrate 10 to each other. The contacts 20 are electrically connected to the holes 14 through a plurality of conductive traces 24 and a Z-conductive layer is attached to the lower surface of the substrate 10. The electrical continuity between the lower surface of the Z-conductive layer and the holes 14 is limited to the Z-axis of the Z- conductive layer in accordance with a prescribed pitch.