Electronic microscopy is based on the same principle as optical microscopy, with the only difference that the relevant rays are constituted by a group of electrons rather than visible light. The Scanning Electronic Microscope (SEM) enables a reflected image of the sample to be obtained (magnified up to 100,000 times or more) that highlights details (like the “depth effect”) that are otherwise impossible to observe. The SEM examination technique is used to study solid materials. The preparation of the sample consists of turning it into a conductor (if it is not already) by using a mix of carbon and layers of gold-palladium and includes variants depending on the materials and the purpose of the analysis.
Electronic micro-analysis by x-rays (SEM + Microprobe Energy-dispersive Spectroscopy (EDS))
This tool is extremely useful in studying surfaces; it has “x-ray microprobes” installed in the SEM. It consists of a system where the regular bombarding of the sample by electrons generates fluorescent x-rays. This device enables the chemical micro-analysis of the material, the reliability of which is exceptional.