Atomic-Force Microscopy (STM)
Atomic-force microscopy is similar to scanning-tunneling microscopy (STM) in that it can image surfaces at atomic-scale resolution. The difference between AFM and STM is that AFM does not require that the sample be an electrically conducting material. Like STM it uses an atomically-sharp tip that is brought very close to the surface. The tip will feel a chemical attraction or repulsion and will move up or down on its supporting cantilever. This movement it monitored by an optical laser beam as the tip is moved laterally across the surface. As in STM, rastering the tip across the surface produces a topographic map of the surface.
/chem-ed/imaging/afm.htm, updated 2/9/97
Copyright © 1997 by Brian M. Tissue, all rights reserved.
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