Scanning Electron Microscopy

Scanning electron microscopy (SEM) is a type of electron microscope that produces high-resolution images of a sample by scanning it with a focused beam of electrons. This technique is used to obtain information about the sample’s surface topography, chemistry, and structure. SEM can achieve resolution of up to 0.2 nanometers, which is much higher than the resolution achieved by light microscopes. The sample is placed in the SEM and a beam of electrons is projected onto it. The electrons interact with the sample’s surface and cause it to emit secondary electrons, which are then collected and focused onto a detector. The detector then creates an image of the sample based on the number and intensity of the secondary electrons. By adjusting the energy of the electron beam, the SEM can be used to image different layers of the sample. The main advantage of SEM is its ability to provide extremely detailed images of a sample’s surface. This makes it well suited for studying fine features such as pores, cracks, and other surface irregularities. It also allows researchers to obtain chemical information about the sample’s composition. By combining SEM with other techniques such as energy dispersive X-ray spectroscopy (EDS) or electron backscatter diffraction (EBSD), researchers can gain a better understanding of the sample’s structure and composition. SEM is a powerful tool for a wide range of applications such as materials science, engineering, medicine, and biology. It can be used to study the surface of a sample in order to better understand how it behaves or to troubleshoot manufacturing defects.