This includes large-area, high-resolution energy-dispersive X-ray spectroscopy (EDS) maps, probing of oxidation states using EELS, and atomic-resolution imaging of material interfaces. With STEM, extremely localized analytical data can be collected for your sample. Its primary advantage over conventional SEM imaging is the improvement in spatial resolution. The strongly focused electron beam interacts with atoms in the excitation volume, which then emit characteristic X-rays. Vibrational electron energy-loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM) has recently emerged as a powerful means of probing the vibrational response of materials at a spatial resolution that is superior to that of other experimental techniques (9, 10). Interactions between the beam electrons and sample atoms allows for simultaneous acquisition of multi-modal data, which is correlated with beam position to build a virtual image in which the signal level at any location in the sample is represented by the contrast of the image. Using state of the art scanning transmission electron microscopy (STEM) it is nowadays possible to directly image single atomic columns at sub- resolution. Transmission electron microscopes have a higher magnification of up to 50 million times, whereas scanning electron microscopes can typically magnify images around 500,000 times. Like SEM, STEM scans a very finely focused beam of electrons across the sample in a raster pattern. Scanning transmission electron microscopy (STEM) has been shown as powerful tools for material characterization, especially after the appearance of aberration-corrector which greatly enhances the resolution of STEM. One of STEM’s principal advantages over TEM is that it enables the use of other signals that cannot be spatially correlated in TEM, including characteristic X-rays and electron energy loss spectra (EELS). Like TEM, STEM requires very thin samples and looks primarily at beam electrons transmitted by the sample. While in TEM parallel electron beams are focused perpendicular to the sample plane, in STEM the beam is focused at a large angle and is converged into a focal point. Scanning transmission electron microscopy (STEM) combines the principles of transmission electron microscopy (TEM) and scanning electron microscopy (SEM). STEM (Scanning transmission electron microscopy) STEM is similar to TEM. Scanning transmission electron microscopy
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