Analytical Electron Microscopy

Scanning Electron Microscope (SEM), Electron Microprobe (EMP)

Since 2012 the modernized and updated laboratories for analytical electron microscopy are in operating state. These labs include two Scanning Electron Microscopes and a modern Electron Microprobe with field emission gun (a state-of-the-art machine for Austria). Furthermore, there is a table-electron microscope installed in showroom 21 (microcosmos) which can be used by museum visitors to observe show objects under a magnification up to 40000 times.
Electron microscopy is applied to study objects down to micro- and even nanometer scale (0,000001 mm) in a structural or analytical way. In contrary to standard light microscopy, the images in an electron microscope are generated by an electron beam which is „shot" at the object of interest and then reflected in different ways by the studied sample, depending on its composition and morphology. Different detectors receive signals from the reflected electrons and convert them into the following informations:
  • Morphology imaging of the studied object up to a magnification of 300000 times in a scanning electron microscope
  • Imaging of different chemical phases also up to a magnication of 300000 times
  • Detailed chemical analysis of the sample, in an electron microprobe down to trace elements (parts per million, ppm scale, 0,0001%)
  • Crystallographic informations, internal deformaton inside the studied object down to micrometer scale (0,001 mm)
  • Internal structures of the studied object (cathodoluminescence)
These types of analytical investigations are common since many years especially in geosciences (mineral- and crystal studies, microfossils etc.). During the last decade electron microspcopy became highly important in many different research areas, especially in material sciences but also in others like biology, archeology, art history and many more. The analytical electron microscopy labs of the NHM are open for all research departments of the museum and perform analyses by order and for account of other research institutions (see below “Services - Electron Microscopy and Electron Microprobe“).