A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. The electrons interact with electrons in the sample, producing various signals that can be detected and that contain information about the sample's surface topography and composition. The electron beam is generally scanned in a raster scan pattern, and the beam's position is combined with the detected signal to produce an image. SEM can achieve resolution better than 1 nanometer. Specimens can be observed in high vacuum, low vacuum and in Environmental SEM specimens can be observed in wet condition.
Read more about Scanning Electron Microscope: History, Principles and Capacities, Scanning Process and Image Formation, Sample Preparation, Detection of Secondary Electrons, Detection of Backscattered Electrons, Beam-injection Analysis of Semiconductors, Cathodoluminescence, X-ray Microanalysis, Resolution of The SEM, Environmental SEM, 3D in SEM, Gallery of SEM Images