Mapping the process dependent conductivity of carbon nanotube thin-films using a non-invasive contact probing system.

We report on a non-invasive contact probing (NICP) system for measuring the distribution of local surface conductivity of macroscopic thin-films of carbon nanotubes. Using the NICP system, we were able to obtain the local sheet resistance of the conducting thin-films continuously at ∼10 μm resolution over few centimeters which would not have been possible using conventional contact probing methods. Measurements performed on carbon nanotube thin-films with various nanotube densities, physical, and chemical treatments revealed that the local variation in electrical characteristics was not reflected in global conductance measurements. This demonstrated the usefulness of the NICP system for evaluating the effect of processing on the electrical uniformity of conducting thin-films made using nanomaterials.