In situ manipulation and electrical characterization of multiwalled carbon nanotubes by using nanomanipulators under scanning electron microscopy

摘要

The results of in situ manipulation and electrical transport characterization of individual multiwalled carbon nanotubes (MWCNTs) grown on a nickel tip by using a piezoelectric nanomanipulation system operating in a scanning electron microscope chamber have been reported. The growth of MWCNT directly on nickel wire by chemical vapor deposition technique ensures good electrical contact with the catalyst substrate. Using the electron beam induced welding, a full characterization of electronic properties of several MWCNTs has been explored without the usual postprocessing methods which may alter, in principle, the intrinsic properties of the carbon nanotube (CNT). Thanks to the high mechanical and electrical stability ensured by the electron beam welding procedure, a detailed study of the modification of CNT electrical transport properties under CNT buckling has been performed. The crucial role played by the structural defects in determining an irreversibility of a long MWCNT I-V characteristic under mechanical stress has been clearly evidenced. Finally, by a proper sequence of CNT/tip welding and movement, the potential in creating an Ohmic junction between two nanotubes has been demonstrated, opening the route to a systematic investigation of one of the most fundamental aspect of CNT physics.