Patent ID: 8841172

Claim:
A method for forming a package substrate, comprising steps of: providing a metal plate having a first surface and a second surface opposing to the first surface; forming a plurality of trenches on the first surface of the metal plate, wherein the trenches are crossed to each other and arranged alternately for dividing the first surface of the metal plate into a plurality of regions; providing insulation material in the trenches; removing metal plate material under the second surface of the metal plate, and exposing the insulation material in the trenches from the first and second surfaces of the metal plate to form a substrate body having two surfaces opposing to each other, wherein the substrate body includes a conductive portion made of the metal plate, and an insulation portion made of the insulation material; and forming a plurality of bonding layers on the two surfaces of the substrate body, wherein the bonding layers are in contact with the conductive portion and the insulation portion so as to be conducted via the conductive portion for heat dissipation, and separated from one another by the insulation portion.