Tuesday, July 18, 2006

US Patent 7076871 - Ohmic Contact With Nanotube Using Evaporaton


In order for individual nanotubes to be used to construct electronic devices bonding between nanotubes and electrodes must be accomplished. This has usually been accomplished by fusion bonding, in which high temperatures are used to facilitate the connection. Unfortunately the high temperatures can also damage the nanotubes. This patent proposes an alternative that uses a scanning probe tip for field evaporation of titanium particles to accomplish the bonding at lower temperatures. Claim 1 reads:

1. A method of manufacturing a carbon nanotube device including an inner electrode, the method having a connecting step that connects a carbon nanotube to the inner electrode, wherein the connecting step comprises: attaching a conductor in a particulate form to an end or periphery thereof of a needle-shaped or rod-shaped carrying electrode; arranging the carbon nanotube in contact with or close to a predetermined connection part of the inner electrode; approaching the end of the carrying electrode on which the particulate form conductor is carried to the connection part; and transferring the particulate form conductor carried on the carrying electrode to the connection part or periphery thereof to connect the carbon nanotube to the inner electrode.