Atomic force microscope vertical resolution

In atomic force microscopy (AFM), the sharp tip of a microscopic probe attached to a flexible cantilever is drawn across an uneven surface such as a membrane (Fig. 1). Electrostatic and van der Waals interactions between the tip and the sample produce a force that moves the probe up and down (in the z dimension) as it encounters hills and valleys in the sample. A laser beam reflected from the cantilever detects motions of as little as 1 A. In one type of atomic force microscope, the force on the probe is held constant (relative to a standard force, on the order of piconewtons) by a feedback circuit that causes the platform holding the sample to rise or fall to keep the force constant. A series of scans in the x and y dimensions (the plane of the membrane) yields a three-dimensional contour map of the surface with resolution near the atomic scale—0.1 nm in the vertical dimension, 0.5 to 1.0 nm in the lateral dimensions. The membrane rafts shown in Figure ll-20b were visualized by this technique. 

Surface Uniformity A Sloan Dektak IIA profilometer and a Burleigh (Metris 2000) Atomic Force Microscope (AFM) was used to examine the polished copper surfaces of the wafers. The Dektek Profilometer is capable of a vertical resolution of 5 A°. The stylus radius is 12.5 A . The scanning rate was medium and a length of 250 micron was scanned in each run. The values of... 

Atomic force microscopy, often abbreviated as AFM, is one of the elected techniques for fine surface and geometrical characterization. Atomic force microscopes provide three-dimensional reconstruction of surface topographies with subnanometer vertical and lateral resolution, over a range which is typically no larger than a few tens or hundreds of micrometers. 

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