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ISSN Online: 2377-424X

ISBN Print: 978-1-56700-474-8

ISBN Online: 978-1-56700-473-1

International Heat Transfer Conference 16
August, 10-15, 2018, Beijing, China

CHARACTERIZATION OF THERMAL AND ELECRICAL CONTACT RESISTANCE BETWEEN METALLIC NANOWIRES AND ELECTRODES

Get access (open in a dialog) DOI: 10.1615/IHTC16.nmt.021297
pages 7107-7115

Sinopsis

Micro/nanoscale devices based on nanowires have attracted increasing attention, and contacts and interfaces have been recognized as an important aspect in energy transport in the nanostructures and nanodevices. To characterize the thermal and electrical resistances between nanowire and Au electrodes, the two-probe and four-probe experiments are conducted on the same Ag nanowire. Three different Ag nanowires with length of 5, 10 and 15 ?m are detected using a microscale device. The electrical contact can be significantly improved by covering polyvinylpyrrolidone (PVP) with thickness of about 2-3 nm, but the reported value changes case by case, ranging from few to hundreds of Ohms, which can be possibly explained by the randomly distributed roughness of nanowire and electrodes. The electrical resistance is almost temperature-independent, indicating that the ballistic transport across the contacts is dominated, and the Wiedeman-Franz (W-F) law is crudely valid. The contact can be further stabilized by using the electron-beam-induced deposition (EBID) method. The thermal contact resistance is negligible small, but the corresponding electrical resistance cannot be ignored. Due to the parasitic thermal conduction, the EBID-enhanced contact violates the W-F law. The thermal contact resistance per unit length between the supported nanowire and the electrode is calculated using a current-heating fin model, which is found to be about two orders smaller than the reported value of the carbon nanotube/substrate contact. The observed phenomenon described in this paper provides insights into improving the management of electrical and thermal transport across metallic contacts, thus has important implications for the energy management of microscale devices.