Backscattered Electron Detector Introduction in Scanning Electron Microscope

Interaction of an accelerated electron beam with a sample target produces a variety of elastic and inelastic collisions between electrons and atoms within the sample. Elastic scattering changes the trajectory of the incoming beam electrons when they interact with a target sample without significant change in their kinetic energy. Backscattered electrons (BSE) are incident electrons reflected back from a target specimen by elastic scattering and imaged with scanning electron microscope (SEM). BSE detectors are typically placed above the sample in the sample chamber based on the scattering geometry relative to the incident beam often with separate components for simultaneous collection of back-scattered electrons in different directions. BSE detectors above the sample collect electrons scattered as a function of sample composition.