Scanning Electron Microscopy
The scanning electron microscope is a type of electron microscope whose technology has been developed since the 1950s; the most recent instruments reach a resolution of less than a nanometer (one millionth of a millimeter), allowing much more detailed information than a common optical microscope (which commonly presents a maximum resolution in the order of hundreds of nanometers).

When equipped with a detector for energy dispersive spectroscopy (EDX), a SEM can be used to determine the elements present in a sample of unknown composition. The working principle of the SEM is based on the interaction between an electron beam, focused on the sample, and the electrons of the atoms which constitute the sample. The result of this interaction leads to the emission of several signals, mainly electrons (secondary and backscattered) and X-rays, which are then analyzed with different sensors.

The SEM, combined with EDX spectroscopy, represents an indispensable tool for research in various scientific fields, from materials science to biology. It is able to provide basic information which are difficult to obtain with other investigation techniques; such information can be used, for example, in order to assess the impact of the introduction of innovative processing techniques on product characteristics.

From August 2014, a JEOL 6010-LA SEM equipped with an EDX sensor has been made available at MEMTi. The instrument is used for both research and education at the Institute and is available as a service for local companies and institutions that need SEM and EDX analysis for development and control of their products and processes.

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