Fluctuation-induced tunneling conduction through RuO₂ nanowire contacts

A good understanding of the electronic conduction processes through nanocontacts is a crucial step for the implementation of functional nanoelectronic devices. We have studied the current- voltage (I - V) characteristics of nanocontacts between single metallic RuO₂ nanowires and contacting Au electrodes, which were pre-patterned by simple photolithography. Both the temperature behavior of contact resistance in the low-bias voltage ohmic regime and the I - V curves in the high-bias voltage non-ohmic regime have been investigated. We found that the electronic conduction processes in the wide temperature interval 1-300 K can be well described by the fluctuation-induced tunneling (FIT) conduction theory. Taken together with our previous work [Lin, Nanotechnology 19, 365201 (2008)], where the nanocontacts were fabricated by delicate electron-beam lithography, our study demonstrates the general validity of the FIT model in characterizing electronic nanocontacts.