Microscopes, Scanning Probe
Definition : Microscopes that can image and measure the surface of a sample in all three dimensions (i.e., topographic images) with a typical resolution of a few nanometers. These microscopes consist of a scanning system, a probe, and a sensor; they also have computer capabilities for microscope operation and to process and display the image information. Scanning probe microscopes employ one or more techniques to measure surface characteristics, including scanning tunneling microscopy (STM), using a very sharp conducting tip for scanning on a conducting surface while measuring variation in electric current, and atomic force microscopy (AFM), which applies a force in the range of the interatomic forces that holds the tip of a cantilever either in contact with or at a fixed distance from the sample surface while measuring its displacement. In addition to the topography of the surface, some scanning probe microscopes can measure other sample surface characteristics, such as magnetic force, electric field, and temperature gradients. Scanning probe microscopes are used to evaluate biological samples in air, vacuum, or liquid environments without previous preparation (e.g., staining, coating), including intracellular structures, cellular movement, and the interaction of bacteria with biomaterials.
Entry Terms : "Scanning Thermal Microscopes" , "Electric Field Microscopes" , "Magnetic Force Microscopes" , "Lateral Force Microscopes" , "Scanning Tunneling Microscopes" , "Atomic Force Microscopes" , "Scanning Probe Microscopes"
UMDC code : 18566