rasterelektronmikroskop

Rasterelektronenmikroskopie, often abbreviated as REM or SEM (Scanning Electron Microscope), is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. As the electron beam interacts with the atoms on the sample's surface, it generates various signals that can be detected and used to form an image. These signals include secondary electrons, backscattered electrons, and characteristic X-rays. Secondary electrons, which are emitted from the sample's surface, are most commonly used for imaging and provide high-resolution topographic information. Backscattered electrons, which are high-energy electrons that have been scattered back from the sample, are sensitive to the atomic composition of the sample and can reveal differences in elemental makeup.

The primary advantage of REM is its ability to achieve very high magnifications and resolutions, allowing for the visualization of extremely fine details on a sample's surface. This makes it invaluable in a wide range of scientific fields, including materials science, biology, geology, and nanotechnology. REM instruments typically have a vacuum chamber to house the sample and the electron column, as well as detectors for the emitted signals and a computer system for image acquisition and processing. Sample preparation is often required, which can involve coating non-conductive samples with a thin layer of conductive material like gold or carbon to prevent charge buildup. The resulting images are typically black and white, representing the intensity of the detected signals.