High temperature resistance of small diameter, metallic single-walled carbon nanotube devices

The effects of high temperature cycling on the resistance of metallic single-walled carbon nanotube (SWCNT) devices is measured in situ. Individual, small-diameter SWCNTs contacted by palladium or titanium electrodes were measured from room temperature up to 1000 K in ultrahigh vacuum. Upon the first thermal cycling, the device resistances fluctuate and generally decrease. Pd-contacted devices typically become stable by 450 K, whereas Ti-contacted devices require higher treatments above 600 K. Once these temperatures have been exceeded, subsequent thermal cycling has minimal effects. Heat-treated devices exhibit linear temperature dependences, with Pd and Ti contacts producing average temperature coefficients of -3× 10-4 K and 1.1× 10-3 K, respectively.