The Zeiss EVO 15LS analytical scanning electron microscope is a very versatile instrument suited to diverse imaging and analytical functions.
This is the most frequent application, done before detailed composition analysis is performed. Backscattered electron images (BEI) are the most common pictures taken. They show variation in composition across the sample as different grey tones.
Composition analysis can then be performed using the Cameca SX100 electron microprobe.
This can be done for conductive or metal-coated specimens, including biological ones. Other microscopes suitable for this application are the LEO 1455VP and the Philips XL30.
This type of imaging is ideal for examining important museum specimens where their preservation is vital as it doesn’t damage their surface.
These can be used for colour anaglyphs or even 3D models whose size and shape can be measured.
The EDX detector is routinely calibrated for analysis of major elements in silicates, the most common rock-forming minerals, and can very rapidly give information necessary for mineral identification.
The microscope can be controlled automatically by the EDX detector computer and can be programmed to make maps of large areas of the sample. These show differences in composition across centimetre-scale areas and allow measurement of areas.
Analyses can be taken at pre-selected locations, and the program can hunt for particles of interest.
If elements are present at very low concentrations or the EDX cannot separate their signals the WDX detector can be used to create spectrum scans. The Cameca SX100 electron microprobe also has WDX detectors.
The cathodoluminescence detector can be used to create images from light emitted by a sample. The images can be used to gain information about the history of mineral deposition and crystal growth.