Rapid imaging of nanotubes on insulating substrates

Abstract
We demonstrate the use of field-emission scanning electron microscopy for rapid imaging of small-diameter carbon nanotubes on insulating SiO2 substrates. The image contrast stems from local potential differences between the nanotube and substrate and is insensitive to surface roughness and defects. This technique may also be used as a probe of the electrical connectivity of small structures without external leads.