Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) microanalysis

The Geo Laboratory at the Natural History Museum (NHM-UiO) is equipped with a Hitachi S–3600N Scanning Electron Microscope (SEM), installed in 2004, which is suitable for high-resolution imaging of geological materials (minerals, microfossils) and semi-quantitative X-ray microanalysis of both conductive and non-conductive specimens. 

The Hitachi S–3600N SEM can be operated in two modes:

  • High-vacuum (HV) mode (< 1 Pa). Used for high-resolution imaging and semi-quantitative X-ray microanalysis of conductive samples or coated samples. 
  • Variable pressure (VP) mode (10–200 Pa). This allows observation of non-conductive samples in their natural state or in a wet condition, without the need for coating. 

Instrument Features

  • High-resolution secondary (SE) and backscattered (BSE) electron detectors.
  • Bruker XFlash® 5030 energy dispersive X-ray detector (EDX), running on Quantax 400 (Esprit 1.9), for semi-quantitative elemental analysis and hyperspectral mapping, with <127 eV FWHM at MnKα energy resolution. 
  • Large chamber accommodating samples up to 150 mm in diameter and ~50 mm in height.
  • A 5-axis motorized stage with eucentric tilt (0 – 52°, depending on sample size) and 360° rotation.

Examples of images

list

Sample Preparation Equipment

Electrically insulating samples may be coated with a thin layer of conducting material, e.g. carbon, gold or some other metal alloy. The choice of material depends on the data to be acquired; carbon is most desirable for elemental analysis, while metal coatings are most effective for high-resolution imaging.

  • Agar Auto Carbon Coater, designed to evaporate conducting carbon layers on the SEM/EDX samples to prevent charging effects.
  • Jeol Fine Coat Ion Sputter, JFC-1100 with a PtPd metal alloy target.

Prices

The SEM is available for rent with or without an operator. Prices are in NOK excl. VAT.

Internal users with operator 400 NOK/hour
External users without operator 800 NOK/hour
External users with operator 1500 NOK/hour
Tags: SEM, BSE, EDX, EDS, variable pressure, mineralogy, paleontology, microanalyses
Published Feb. 12, 2019 9:15 AM - Last modified June 6, 2019 1:35 PM