Fabrication and electrical characterization of circuits based on individual tin oxide nanowires

Abstract

Two- and four-probe electrical measurements on individual tin oxide(SnO2) nanowires were performed to evaluate their conductivity andcontact resistance. Electrical contacts between the nanowires andthe microelectrodes were achieved with the help of an electron- andion-beam-assisted direct-write nanolithography process. High contactresistance values and the nonlinear current-bias (I-V) characteristicsof some of these devices observed in two-probe measurements can beexplained by the existence of back-to-back Schottky barriers arisingfrom the platinum-nanowire contacts. The nanoscale devices describedherein were characterized using impedance spectroscopy, enablingthe development of an equivalent circuit. The proposed methodologyof nanocontacting and measurements can be easily applied to othernanowires and nanometre-sized materials.