Comparative friction measurements of InAs nanowires on three substrates

In English We have investigated friction between InAs nanowires and three different substrates: SiO2, fluorosilanized SiO2, and Si3N4. The nanowires were pushed laterally with the tip of an atomic force microscope and the friction force per unit length for both static and sliding friction was deduced from the equilibrium shape of the bent wires. On all three substrates, thick wires showed a difference between sliding and static friction of up to three orders of magnitude. Furthermore, all substrates display a transition to stick-slip motion for nanowires with a diameter of less than about 40 nm. Hydrophobic and hydrophilic substrates display similar friction behavior suggesting that a condensed water layer does not strongly influence our results. The patterns and trends in the friction data are similar for all three substrates, which indicates that they are more fundamental in character and not specific to a single substrate. (C) 2010 American Institute of Physics. doi: 10.1063/1.3503876