Scanning electron microscopy uses electron beams instead of light to produce the images. As a result, a significantly higher resolution is achieved. The scanning electron microscope images surfaces of samples with a three-dimensional perspective, wherein the large depth of focus is of particular importance. Electrons emitted from an electron source are condensed into a fine beam. This beam moves in a well-defined grid over the sample surface. The electrons emitted by the interaction with the primary beam from the sample surface are captured by detectors and converted into an image: the secondary electron (SE) imaging enables the representation of the topography of the sample surface; the backscattered electron (BSE) image also provides information about the different composition of the sample surface (in BSE mode: bright spots – heavier elements, dark spots – lighter elements).
Topography and structure
Cross-section analysis and microstructure