Common heat spreader: Cu More expensive and commercially available heat spreaders: capillary driven fluid convection devices, diamond, SiC

Interface materials are subject to challenging requirements, including the ability to reduce thermal stress between region with vastly differing thermal expansion coefficients. Common Thermal interface materials a variety of polymer based materials with high thermal conductivity particle inclusions, typically with 1-25 micro meter. Effective thermal conductivity is around 2 W/mK Metallic TIMs are less attractive due to their high mechanical stiffness.

Thermal Transport in one dimensional nanotubes and nanowires k of single wall carbon nanotube: 6000W/mK k of Randomly aligned mat of nanotube ropes=35 W/mK For a large density >200 W/mK

Field effect transistor

Graphene- the latest of the discovered allotropes of carbon: k=