What is the Scanning Electron Microscopy (SEM) Technique

What is the Scanning Electron Microscopy (SEM) Technique

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 atoms 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 a resolution better than 1 nanometer. Specimens can be observed in high vacuum, in low vacuum, in dry conditions (in environmental SEM), and at a wide range of cryogenic or elevated temperatures.

Scanning electron microscopy is used in materials science for research, quality control, and failure analysis. In modern materials science, investigations into nanotubes and nanofibres, high temperature superconductors, mesoporous architectures, and alloy strength, all rely heavily on the use of SEMs for research and investigation. In fact, just about any material science industry, from aerospace and chemistry to electronics and energy usage, has only been made possible with the help of SEMs.