Electrical characterization of suspended Pt nanowires grown by EBID with water vapour assistance

Suspended nanowires (SNWs), 600nm-long, 20nm-wide and 30nm-thick, were grown by electron beam-induced deposition of metallorganic Pt, with and without water vapour assistance, and electrically characterized at room temperature. SNWs have Ohmic behaviour in the (−0.1, 0.1V) range, and show conductivity improvement and structural evolution as subsequent I–V cycles are applied; both effects being enhanced by water vapour assistance. Typical resistivities after two I–V cycles are 1–3×10−4Ωm and 6–8×10−5Ωm, for Pt and (Pt+water) depositions, respectively. Structural evolution consists of a progressive coalescence of the Pt nanocrystals into large (15–20nm) and separated grains, leaving wide regions essentially made of carbon material. I–V characteristics over an extended (−2, 2V) range show a non-linear behaviour outside the (−0.4, 0.4V) interval, with currents up to ∼90μA at 2V, corresponding to current densities of ∼1×107A/cm2.