AVS 51st International Symposium
    Nanometer-scale Science and Technology Thursday Sessions
       Session NS2-ThM

Paper NS2-ThM3
Fabrication of Gold Nanowires by Non-contact Atomic Force Microscopy

Thursday, November 18, 2004, 9:00 am, Room 213D

Session: Nanowires I
Presenter: M.E. Pumarol, McGill University, Canada
Authors: M.E. Pumarol, McGill University, Canada
Y. Miyahara, McGill University, Canada
P. Grutter, McGill University, Canada
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Interfacing nanostructures to the macroscopic world is fundamental for their study and possible electronic applications. SPM-based metal deposition techniques are an attractive approach for this goal: due to their easy implementation and the possibility of a maskless direct modification of the surface. These techniques exploit the very intense electric field that appears when an SPM tip is in close proximity with a surface and a potential difference is applied. Here we use a commercial AFM operated in a dynamic mode and in ambient conditions for direct writing /patterning of gold nanowires. For their fabrication, voltage pulses of 20 â?" 30V are applied to a gold coated AFM tip and an insulating surface with a finite tip-surface gap of several nanometers. This produces gold dots with lateral dimensions from under 10 nm to 100 nm, and by increasing the deposition duty cycle dots are overlapped to form a nanowire. Control of the tip sample separation is critical to ensure the reliability and reproducibility of the deposition process. In this work, we use an innovative non-contact based technique to precisely control this separation and by extension the electric field. An advantage of this method of deposition is the ability of locating the part of the sample to which the nanowire will be contacted / attached. Here, we bridge gold macro-electrodes, deposited by EBL, by forming a nanowire between them. A new way for overcoming proximity effects of the AFM tip with a protruding electrode is presented. In the future, this technique will be useful for attaching contact leads to nanostructures like q-dots, nanodots, nanoparticles, and others.