PACKAGING ARCHITECTURE WITH COAXIAL PILLARS FOR HIGH-SPEED INTERCONNECTS

Embodiments of a microelectronic assembly comprise a microelectronic assembly, comprising: a package substrate; an interposer coupled to the package substrate, the interposer comprising a dielectric material, a conductive pillar) through the dielectric material and a conductive structure at least partially surrounding the conductive pillar, the conductive structure separated from the conductive pillar by the dielectric material; and an integrated circuit (IC) die coupled to the interposer on a side opposite to the package substrate. The conductive pillar conductively couples the IC die to the package substrate, and the conductive structure is coupled to a ground connection.