Growth of single-crystalline RuO2 nanowires with one- and two-nanocontact electrical characterizations

Single-crystalline RuO2 nanowires were grown by using a thermal evaporation method. A control of the sizes (width and length) and the length-to-width ratio of the nanowires were achieved by tuning the growth time. A transmission electron microscope–scanning tunneling microscope technique invoking one-nanocontact electrical characterization was adopted to determine the room-temperature resistivity (∼100μΩcm) of the nanowires. An e-beam lithography technique facilitating two-nanocontact measurements was performed to establish the metallic characteristic of individual nanowires. The authors found that a nanocontact may introduce high contact resistance, nonlinear current-voltage characteristics, and even semiconducting behavior in the temperature dependent resistance.