Atomic Force Microscopy–AFM

Atomic force microscopy is a powerful, high-resolution technique capable of recording topographic images of a wide variety of samples. Two key strengths of AFM are its ability to produce images in almost any environment—in air, vacuum, or solvent—and to measure a wide variety of physical properties of the sample. First, this article discusses how the atomic force microscope operates, beginning with a background and general principles and then describing all the major components of the atomic force microscope. Second, all the most commonly used modes of AFM are described, including contact and oscillating modes; lateral force microscopy; modes that measure mechanical properties, magnetic force microscopy, and electrical modes; and force spectroscopy and nanoindentation. Finally, several example applications are given with the focus on measurements with particular relevance to chemistry. These include electrochemical AFM, high-resolution imaging, measurement of molecular interactions, AFM-based nanolithography, and characterization of heterogeneity in polymeric systems.

Keywords: atomic force microscopy; surface analysis; scanning probe microscopy