Packaging architecture with thermally conductive integrated circuit bridge

An IC die, comprising:

• a substrate;
• and
• a metallization stack parallel and adjacent to the substrate,
• wherein:
• the metallization stack comprises electrically conductive pathways,
• a first side of the IC die proximate to the metallization stack is coupled to at least two other IC dies by die-to-die (DTD) interconnects,
• a second side of the IC die opposite to the first side is coupled to a package substrate having thermal vias extending through a thickness of the package substrate,
• the IC die is surrounded on its remaining sides by an organic dielectric material, and
• a thermally conductive material is between the second side of the IC die and the package substrate and in contact with the thermal vias, wherein:
• the thermally conductive material comprises graphite and an adhesive material,
• the IC die is attached to the package substrate by the adhesive material,
• the adhesive material forms a ring along a periphery of the IC die, and
• the graphite is enclosed within the ring of the adhesive material.

A method for fabricating a microelectronic assembly, the method comprising:

• providing a package substrate having a first surface, an opposing second surface, and at least one thermal via through the package substrate between the first surface and the second surface such that a portion of the thermal via is exposed on the first surface;
• depositing a thermally conductive material on the exposed portion of the thermal via, wherein depositing the thermally conductive material comprises:
• applying an adhesive paste or film in a shape of a ring around the exposed portion of the thermal via, the ring having an inner perimeter and an outer perimeter;
• and
• placing a sheet of graphite within the inner perimeter such that the graphite is in contact with the exposed portion of the thermal via;
• depositing electrically conductive traces and conductive pillars on the first surface;
• coupling a first IC die to the thermally conductive material;
• depositing an organic dielectric on the first surface around the first IC die, the conductive traces and the conductive pillars;
• exposing contact pads on the first IC die opposite to the package substrate;
• and
• coupling a second IC die and a third IC die to the contact pads, wherein at least one conductive pathway in the first IC die electrically couples the second IC die and the third IC die.