Atomic force microscopy
Scanning tunnelling microscopes were the precursors to atomic force microscopes and have proved revolutionary across all scientific disciplines in the study of nanoscale surfaces and interfaces; so much so that its inventors Heinrich Rohrer and Gerd Bining received the Nobel Prize for Physics in 1986.
The reason for their importance is the relative simplicity of operation, with contrast to scanning electron microscopes or transmission electron microscopes which require complex preparation conditions by requiring the sample to be coated with gold or cooled respectively. For a nano-scientist to examine a sample surface that is going to have a room temperature application it is obvious that the best way to study its behaviour is to study it under these same conditions. This is essentially what scanning probe microscopes (SPM’s) have allowed every nano-scientist to do. A simple atomically sharp physical probe is brought close to the surface and moved across the surface using piezo crystal stacks that provide high resolution control of the tip in the x, y and z axes. The type of SPM being performed dictates what information is recorded and the specific type of tip probe.