Tuesday, January 27, 2009

US Patent 7481267 - Anisotropic thermal CNT/ceramic film


This patent from the University of California System teaches an improved anisotropic thermal interface achieved by carbon nanotube ceramic composites. Claim 1 reads:

1. In an application requiring the conduction of heat between an exothermic device and a heat sink surface, the improvement comprising:

interposing between said exothermic device and said heat sink surface a heat-spreading layer of a composite comprised of carbon nanotubes dispersed in a matrix of ceramic material, said composite having been uniaxially compressed in a direction transverse to said heat sink surface to provide said composite with a thermal diffusivity in said transverse direction that is lower than the thermal diffusivity in directions parallel to said heat sink surface.

The basic research behind this patent is described in the article "Anisotropic thermal properties of single-wall-carbon- nanotube-reinforced nanoceramics" by Zhan et al.