When the incident electron hits the sample, surface area of the
sample are very much vulnerable to get that electron, they absorb the electron
that comes in but they themselves release some electrons which is called
secondary electrons. The electron that goes inside which is absorbed is primary
electrons. So the electrons they release from them their selves that are called
secondary electrons. The interaction range is only few nanometres and it is low
Using secondary electrons we can study the surface topography and composition of the molecules.
Backscattered electrons are another type of signal that comes
out from the sample surface when the incident beam of electrons bombards to the
sample. Some electrons will be reflected whichever electron comes in. In simple
words back scattered electrons are primary beam of electrons scattered back out
of sample. It comes from the surface and from the deeper within the specimen.
The Backscattered electrons can be used to study the atomic number and topography and even
composition of the molecules can be determined.
When the incident beam of electrons strikes the surface of the
specimen, some amount of electrons are also absorbed, so no electrons comes
out, they absorb the electrons. Some region of the specimen can absorb the
electrons, that absorption can give rise to specific x-ray radiation. In simple
words, as an effect of interaction between the sample and the electron beam,
the primary electron will be slowed down or break and do the conservation of
energy and the electron give off an x-ray to maintain its momentum.
The X-rays can tell us about the Thickness and atomic composition of the molecules.
This is one of the types of signal produced when the electron
beams strikes the sample surface. As a result of interaction photons are
generated and the photons hit an electron from the outer energy levels with
high energy, auger electrons are generated.
atomic composition can be studied using Auger electrons.