The research team from Institute of Physics, Academia Sinica in Taiwan, use carbon nanotubes as a model system for this purpose. The selected single-wall CNT bundle is cut to a length of between 5 and 7 µm using FIB irradiation. It is then placed atop freestanding parallel Au electrodes using a scanning electron microscope (SEM)-based probe station. The resultant device is a through-hole chip comprising Au electrodes with suspended CNT and FIB deposited contacts (as shown in left figure).

Pt contamination

They find that the FIB deposition of Pt on the contact regions can significantly reduce the contact resistance. However, TEM inspections reveal serious Pt contaminations near the deposition areas and on the carbon nanotubes. These contaminations are suspected to be the origin of the observed unstable Coulomb oscillation behaviour (as shown in right figure) in electrical measurement. This finding addresses an important issue about the future application of FIB technology on nanoelectronics.

More information can be found in the journal Nanotechnology 26 055705.

Further reading

Patterning bumpy surfaces (July 2014)
Patterning technique prepares graphene nanoribbons for photodetector applications (Jan 2014)
Nanopores form more quickly through FIB boiling (Jan 2014)