Thursday, October 08, 2009

US Patent 7598127 - CNT fuse

Nantero has focused most of their patents on mechanical switches based on carbon nanotubes for applications in non-volatile memory and programmable logic. This patent takes a slightly different approach including claims to a nanotube fuse operable under Joule heating. Claim 3 reads:

3. A carbon nanotube fuse comprising:

a carbon nanotube layer,

a cap layer formed directly over the carbon nanotube layer, where the cap layer is formed of a material that has an insufficient amount of oxygen to significantly oxidize the carbon nanotube layer under operating conditions, and is otherwise sufficiently robust to protect the carbon nanotube layer from oxygen and plasmas, the cap layer formed at a smaller size than the carbon nanotube layer, to expose a contact area at distal ends of the carbon nanotube layer, and

electrically conductive contacts disposed on each of the two distal ends of the carbon nanotube layer and in electrical continuity with the carbon nanotube layer through the contact area, where the contact area is of a size sufficient for at least one of the contacts to ablate from the carbon nanotube layer upon application of a current that causes a Joule heating effect in the carbon nanotube layer.