title: Controlling nanowire growth through electric field-induced deformation of the catalyst droplet.
abstract: Semiconductor nanowires with precisely controlled structure, and hence well-defined electronic and optical properties, can be grown by self-assembly using the vapour-liquid-solid process. The structure and chemical composition of the growing nanowire is typically determined by global parameters such as source gas pressure, gas composition and growth temperature. Here we describe a more local approach to the control of nanowire structure. We apply an electric field during growth to control nanowire diameter and growth direction. Growth experiments carried out while imaging within an in situ transmission electron microscope show that the electric field modifies growth by changing the shape, position and contact angle of the catalytic droplet. This droplet engineering can be used to modify nanowires into three dimensional structures, relevant to a range of applications, and also to measure the droplet surface tension, important for quantitative development of strategies to control nanowire growth.
authors.affiliation: Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK.|IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA.
authors.forename: Federico
authors.initials: F
authors.lastname: Panciera
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Norton
authors.affiliation: Department of Micro and Nanotechnology, Technical University of Denmark, Kongens Lyngby DK-2800, Denmark.
authors.forename: Sardar B
authors.initials: SB
authors.lastname: Alam
authors.affiliation: Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK.
authors.forename: Stephan
authors.initials: S
authors.lastname: Hofmann
authors.affiliation: Department of Micro and Nanotechnology, Technical University of Denmark, Kongens Lyngby DK-2800, Denmark.
authors.forename: Kristian
authors.initials: K
authors.lastname: Mølhave
authors.affiliation: IBM T.J. Watson Research Center, Yorktown Heights, New York 10598, USA.
authors.forename: Frances M
authors.initials: FM
authors.lastname: Ross