Scanning Electron Microscope

A scanning electron microscope (SEM) utilizes a focused beam of electrons to probe a rectangular area on a solid surface of interest. When the beam of electrons hits the solid surface at each probed location, some of the energy carried by the beam of electrons is converted to other types of energy like emission of electromagnetic waves such as secondary electrons, visible light, x-rays, and heat. The SEM captures any of these emissions (like the secondary electrons for imaging for example) and utilizes them to recreate an image at each probed location on the surface. The SEM can be used to sample a broad range of area sizes with good 3-D representation of the sample surface. Because the wavelength of the electromagnetic radiation (or captured surface emission) captured by the SEM is much shorter than the wavelength of visible light, electron microscopes in general can reach much greater magnifications than optical microscopes can. However, it is important to keep in mind that some times, the beam of electron hitting the surface can change the surface structure. Here are some images taken with a Zeiss Ultra Scanning Electron Microscope at the CAMCOR Alice C. Tyler Nanofabrication Imaging facility at University of Oregon of a stainless steel sintered porous plate at different magnifications.

Magnification: 84X

Magnification:365X

Magnification:1540X

Magnification:4810X