Scanning Electron Microscopy Laboratory

Laboratory of Scanning Electron Microscopy (SEM) at DiSTAR is equipped with a SEM Jeol JSM5310 and a FESEM ZEISS Merlin VP. They both allow the investigation of the microstructure and morphology of raw inorganic and suitably prepared organic materials, through the acquisition of high resolution magnified digital images.
SEM Jeol JSM5310, in the lab since 1998, provides both 3D images through a secondary electron detector (SE) and topographic and compositional images through a backscattered electron detector (BSE). It is also equipped with an EDS X-Stream Inca Oxford detector that supplies qualitative evaluation of chemical elements starting from fluorine. A well performing reference standardization allows single point analyses of polished samples (resin embedded or thin sections).
The FESEM ZEISS Merlin VP SEM, available in the lab since 2017, works both in high vacuum and in variable pressure and reaches 1 million magnification. The very large vacuum chamber of Gemini 2 apparatus hosts samples up to 15 cm diameter. This SEM is equipped with an “”inlens”” detector of both secondary and backscattered electrons, a normal secondary electron detector and a variable pressure secondary electron detector. It is linked to an EDS Oxford X-Max detector and to a WDS Wave Oxford spectrometer equipped with 4 analytical crystals. The combined use of EDS and WDS analytical facilities allows the quantitative analysis of chemical elements starting from Boron. A dedicated software provides us with compositional maps for the automated evaluation of the mineralogical composition in an unknown sample. The FESEM facility allows non-destructive and non-invasive analyses of large samples, which makes this apparatus the most powerful tool for SEM investigation in cultural heritage and forensic geology fields. The laboratory is officially accredited for SEM analysis of asbestos, on both massive samples and airborne fibers.