Field Ion Microscope

Field Ion Microscope

Field ion microscopy (FIM) is an analytical technique used in materials science. The field ion microscope is a type of microscope that can be used to image the arrangement of atoms at the surface of a sharp metal tip. It was the first technique by which individual atoms could be spatially resolved. On October 11, 1955, Muller & Bahadur (Pennsylvania State University) observed individual tungsten (W) atoms on the surface of a sharply pointed W tip by cooling it to 78 K and employing helium as the imaging gas. Muller & Bahadur were the first persons to observe individual atoms directly; to do so, they used an FIM, which Muller had invented in 1951.