How atomic probe microscopy works

This video from the Australian Centre for Microscopy and Microanalysis at the University of Sydney demonstrates how atomic probe tomography delivers the highest spatial resolution in three dimensions of any microscopy technique. It is said to be the only material analysis technique capable of both 3D imaging and chemical composition measurements at the atomic scale.

The sample is prepared in the form of a very sharp tip. The cooled tip is biased at high DC voltage, which induces a very high electrostatic field at the tip surface, just below the point of atom evaporation. Under laser or high-voltage pulsing, one or more atoms are evaporated from the surface, and projected onto a detector,