掃描電鏡SEM
掃描電鏡SEM (Scanning Electron Microscope) was designed for inspecting the topographies of specimens at very high magnifications. Currently the advanced FESEM (Field Emission Scanning Microscopes) can go to magnifications as high as 300,000X. Due to the operation flexibilities and good imaging capabilities, SEM has been widely used to inspect sample Topographies and Morphologies.
During SEM inspection, the focused energetic electron beam is scanning on sample surface being inspected, resulting in the transfer of energy to the spot focused. These injected bombarding electrons, also referred to as primary electrons, dislodge electrons from the specimen itself. The dislodged electrons, also known as secondary electrons, are attracted and collected by a positively biased grid or detector, and then translated into a signal. After signal amplification and system analysis, these signals will be transmitted into images of sample topography, and revealed on the screen. With assistance of EDX, SEM can also do elemental composition analysis with spot size as small as 1um. EDX analysis is useful in identifying materials and contaminants, as well as estimating their relative concentrations on the surface of the specimen. With Assistance of FIB, SEM is even more powerful to do precision cross-sectioning imaging. |