Atomic force microscopy (AFM) is a very high-resolution type of microscopy with the capacity of Ångström resolution on certain samples. A tip as sharp as one molecule is scanned over the surface. Forces between the tip and the surface result in deflections of the cantilever and these deflections are monitored through a laser beam. We use AFM in combination with foremost ellipsometry and QCM but also in combination with more available instruments such as ATR-FTIR to image and measure changes on a surface at a nanoscale. In many cases, we are interested in the thickness of a film or adsorbed material. We are also looking at the homogeneity of the surface.
A topography scan of an adsorbed material where both the layer thickness (here corresponding to an expected lamellar structure) and the inhomogeneity on the surface is shown.