Atomic-scale roughness effect on capillary force in atomic force microscopy
Jang, J.; Ratner, M.A.; Schatz, G.C., 2006: Atomic-scale roughness effect on capillary force in atomic force microscopy. Journal of Physical Chemistry. B 110(2): 659-662
We study the capillary force in atomic force microscopy by using Monte Carlo simulations. Adopting a lattice gas model for water, we simulated water menisci that form between a rough silicon-nitride tip and a mica surface. Unlike its macroscopic counterpart, the water meniscus at the nanoscale gives rise to a capillary force that responds sensitively to the tip roughness. With only a slight change in tip shape, the pull-off force significantly changes its qualitative variation with humidity.