Patent ID: 8510936

Claim:
A method of forming a package carrier, the method comprising: providing a first copper foil layer, a second copper foil layer on the first copper foil layer, a third copper foil layer and a fourth copper foil layer on the third copper foil layer, wherein the second foil layer is partially bonded the fourth copper foil layer by an adhesive gel; forming a plurality of first through holes extending from the first copper foil layer to the third copper foil layer; compressing a first dielectric layer and a first conductive layer disposed thereon on the first copper foil layer, and compressing a second dielectric layer and a second conductive layer disposed thereon on the third copper foil layer, wherein the first dielectric layer and the second dielectric layer face to the first copper foil layer and the third copper foil layer respectively, and portions of the first dielectric layer and the second dielectric layer fill in the first through holes; patterning the first conductive layer and the second conductive layer to form a first circuit layer and a second circuit layer; compressing a third dielectric layer and a fifth copper foil layer disposed thereon on the first circuit layer and removing the adhesive gel to from a first carrier unit; and forming a plurality of first conductive blind via structures connecting the fifth copper foil layer and the first circuit layer, and forming a plurality of second conductive blind via structures connecting the first copper foil layer and the first circuit layer.