PROBING ELECTRICAL-TRANSPORT IN NANOMATERIALS - CONDUCTIVITY OF INDIVIDUAL CARBON NANOTUBES

A general approach has been developed to determine the conductivity of individual nanostructures while simultaneously recording their struct ure. Conventional lithography has been used to contact electrically si ngle ends of nanomaterials, and a force microscope equipped with a con ducting probe tip has been used to map simultaneously the structure an d resistance of the portion of the material protruding from the macros copic contact. Studies of individual carbon nanotubes demonstrate that the structurally most perfect nanotubes have resistivities an order o f magnitude lower than those found previously and that defects in the nanotube structure cause substantial increases in the resistivity.