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Glossary terms about Secondary Electrons

Secondary Electrons
Produced through inelastic scattering that results in the ejection of loosely bound electrons from the specimen. Secondary electrons have energies from ~2-50eV.


13 pages mention Secondary Electrons

Conventional (high vacuum) scanning electron microscopy (SEM)
This type of machine is used for routine imaging, using either secondary electrons (SE) or backscattered electrons (BSE). 
Cryo-scanning electron microscope (Cryo-SEM)
It is imaged using either secondary electrons (SE) or backscattered electrons (BSE). 
Detectors
Due to the low energies of secondary electrons (SE) (~2 to 50 eV) they are ejected only from near-surface layers. 
Electromagnetic lenses, apertures and beam size
 
Electron-matter interactions
Some electrons are bounced back out of the sample (backscattered electrons), others knock into atoms and displace electrons that, in turn, come out of the sample (secondary electrons); alternatively X-rays, and light or heat (in the sample) can be the result of these interactions. 
Generating an image
For routine scanning electron microscope images, secondary electrons (SE) form the usual image of the surface. 
High vacuum mode and pump system
The high vacuum condition also optimises collection efficiancy, especially of the secondary electrons
Images from electrons
There are a range of imaging techniques available. Image from secondary electrons (below lens SE detector) Zincite (ZnO) powder and tabular crytals of shigate (Mn7AL4(SO4)2(OH)228H2O) showing crystal shape and size. 
Introduction - aims and learning outcomes
 
Recommended reading
 
SEM challenge
The term SE includes all types of secondary electrons
Specimen chamber
A high vacuum condition also optimises collection efficiency, especially of the secondary electrons
Troubleshooting: edge effect, charging, sample damage
They are caused by the effects of topography on the generation of secondary electrons and are what gives form and outline to the images produced by the Secondary Electron detector.