Scanning transmission electron microscopy

Imaging a sufficiently thin specimen using a scanned electron probe and transmitted-electron detectors.

An electron microscope that scans a focused probe across an electron-transparent specimen and records transmitted-electron signals at each scan position. Its image magnification is set by the displayed-to-scanned length ratio, separately from angular detector collection.

Detection of transmitted electrons within an angular annulus excluding the direct beam. Contrast can include diffraction, atomic-number and thickness contributions depending on the collection angles.

A scanning transmission electron microscopy mode collecting electrons scattered to sufficiently large angles. It often gives approximately monotonic atomic-number and mass-thickness contrast, with detector angles and multiple scattering still important.