Abstract: A supported graphene device comprises at least one graphene feature of 1 to about 10 graphene layers having a predetermined shape and pattern, with at least a portion of each graphene feature being supported on a substrate. In some embodiments the device comprises graphene features supported on crystalline semiconductor substrate, such as silicon or germanium. The graphene features on a crystalline semiconductor substrate can be fabricated by forming an amorphous carbon doped semiconductor on the crystalline semiconductor substrate and then epitaxially crystallizing the amorphous semiconductor with carbon migration to the surface to form a graphene feature of one or more graphene layers. The epitaxy can be promoted by heating the device or by irradiation with a laser.

Abstract: A multi-layer heatsink module for effecting temperature control in a three-dimensional integrated chip is provided. The module includes a high thermal conductivity substrate having first and second opposing sides, and a gallium nitride (GaN) layer disposed on the first side of the substrate. An integrated array of passive and active elements defining electronic circuitry is formed in the GaN layer. A metal ground plane having first and second opposing sides is disposed on the second side of the substrate, with the first side of the ground plane being adjacent to the second side of the substrate. A dielectric layer of low thermal dielectric material is deposited on the back side of the ground plane, and a metal heatsink is bonded to the dielectric layer. A via extends through the dielectric layer from the metal heatsink to the metal ground plane.