Probe and Scanner

The probe is the basic SPM component that directly interacts with a sample surface to be examined or measured. Either the probe can scan over a stationary surface, or it can be stationary while the sample surface is moved by a scanner underneath. 

The scanner controls the probe that moves over the sample in three dimensions in a precise way. The scanning probe needs to be positioned with an accuracy of 1 pm (10 12 m) if atomic resolution is required. To achieve this level of precision, a scanner is made from piezoelectric materials. 

Piezoelectric materials change shape in an electric field or generate an electric field due to shape change. The relative length of the change is proportional to applied voltage (E). 

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