Conductance probe microscopy investigation on the local electronic properties of single walled carbon nanotube systems

Abstract

In order to build electronic devices and circuits comprised of nanoscale materials as the active element it is imperative to unravel the local electronic properties of these materials. We have performed an in-depth study on the local electronic behavior of individual single walled carbon nanotubes (SWCNT) and on two dimensional networks based on these tubes using conductance imaging atomic force microscopy (CI-AFM). This technique allows us to simultaneously investigate the morphology and the local electronic structure of the nanotubes, when a metal coated tip is scanned over the surface. SWCNTs solubilised in N-methyl pyrrolidone (NMP) were sprayed onto Si02 substrates to form homogeneous and percolating networks. The electrodes were fabricated using UV-lithographically and these samples were subjected to controlled annealing at 500 degrees Celsius under Ar/H2 atmosphere to remove the adsorbed NMP molecules.