The present invention relates to a method of making a semiconductor package with package-on-package stacking capability. In accordance with a preferred embodiment, the method is characterized by forming through openings that extend through a metallic carrier between first and second surfaces of the metallic carrier, attaching a chip-on-interposer subassembly on the metallic carrier using an adhesive, with the chip inserted into a cavity of the metallic carrier, and with the chip-on-interposer subassembly attached to the metallic carrier, forming first and second buildup circuitry on a first surface of the interposer and the second surface of the metallic carrier, respectively, and subsequently forming plated through holes that extend into the through openings to provide electrical and thermal connections between the first and second buildup circuitry. The method and resulting device advantageously provides vertical signal routing and stacking capability for a semiconductor package.