Explain the principle involved in scanning electron microscope (SEM).

Explanation

In scanning electron microscope (SEM) electrons are focused by means of lenses into a very fine point. The interaction of electrons with the specimen results in the release of different forms of radiation (such as auger electrons, secondary electrons, back scattered electrons) from the surface of the specimen. these radiations are then captured by an appropriate detector, amplified and then imaged on fluorescent screen.