Scanning beam-specimen backscattered electrons

As compared to TEM, scanning electron microscopy (SEM) can avoid destroying the bulky specimen, because a focused electron beam is scanned during catalyst observation. SE and backscattered electron (BSE) signals can be collected separately or together in any ratios simultaneously. Stereoscopic morphologies can be obtained but with resolution much inferior to that of TEM. Similar to TEM, EDS could be applied as accessory to analyze microdomain composition and element distribution. 

Type 3, scanning beam A focused beam (laser tight or electron beam) scans across the specimen, resulting in a reflected beam from the surface (as in a confocal laser scanning microscope) or in secondary or backscattered electrons (in scanning electron microscopes) thick and thin specimens can be studied. 

In this type of Microscopy a fine beam of electrons is scanned across the surface of an opaque specimen to which a light conducting film has been applied by evaporation. Secondary electrons, backscattered elections, or (in the electron microprobe)... 

---