title: Capillarity-Driven Welding of Semiconductor Nanowires for Crystalline and Electrically Ohmic Junctions.
abstract: Semiconductor nanowires (NWs) have been demonstrated as a potential platform for a wide-range of technologies, yet a method to interconnect functionally encoded NWs has remained a challenge. Here, we report a simple capillarity-driven and self-limited welding process that forms mechanically robust and Ohmic inter-NW connections. The process occurs at the point-of-contact between two NWs at temperatures 400-600 °C below the bulk melting point of the semiconductor. It can be explained by capillarity-driven surface diffusion, inducing a localized geometrical rearrangement that reduces spatial curvature. The resulting weld comprises two fused NWs separated by a single, Ohmic grain boundary. We expect the welding mechanism to be generic for all types of NWs and to enable the development of complex interconnected networks for neuromorphic computation, battery and solar cell electrodes, and bioelectronic scaffolds.
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Celano
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: David J
authors.initials: DJ
authors.lastname: Hill
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: Xing
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Pinion
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Christesen
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: Cory J
authors.initials: CJ
authors.lastname: Flynn
authors.affiliation: Vanderbilt Institute of Nanoscale Science and Engineering, Vanderbilt University , Nashville, Tennessee 37235, United States.
authors.forename: James R
authors.initials: JR
authors.lastname: McBride
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-3290, United States.
authors.forename: James F
authors.initials: JF
authors.lastname: Cahoon
keywords: Ohmic junction; Silicon nanowires; capillarity-driven welding; finite-element simulation; percolation network; surface diffusion