### US Patent 7859104 - CNT thermal interface with transition structure

In order to continue the transistor scaling rates predicted by Moore's Law there is an increased interest in fabricating 3D circuit architectures by stacking multiple semiconductor layers. Due to the increased density of these designs more efficient cooling solutions will need to be developed to deal with the increased heat generation. This patent from Hon Hai Precision teaches one such solution using the high thermal transport properties of carbon nanotubes. Claim 1 reads:

*1. A thermal interface material comprising:*

a carbon nanotube array comprising a plurality of carbon nanotubes, spaces being defined between adjacent carbon nanotubes;

a transition structure covering an entire peripheral surface of each of the carbon nanotubes; and

a matrix occupying the spaces and encompassing the carbon nanotubes with each transition structure disposed between the matrix and a corresponding one of the carbon nanotubes;

wherein each of the carbon nanotubes has a length substantially equal to a thickness of the matrix, and each transition structure has a length substantially equal to the thickness of the matrix.

a carbon nanotube array comprising a plurality of carbon nanotubes, spaces being defined between adjacent carbon nanotubes;

a transition structure covering an entire peripheral surface of each of the carbon nanotubes; and

a matrix occupying the spaces and encompassing the carbon nanotubes with each transition structure disposed between the matrix and a corresponding one of the carbon nanotubes;

wherein each of the carbon nanotubes has a length substantially equal to a thickness of the matrix, and each transition structure has a length substantially equal to the thickness of the matrix.

Labels: Hon Hai Precision Industry