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Updated: Jul 19, 2026
08:04
Preparation and Observation of Thick Biological Samples by Scanning Transmission Electron Tomography
Published on: March 12, 2017
A history of scanning electron microscopy developments: towards "wet-STEM" imaging
A Bogner1, P-H Jouneau, G Thollet
1Groupe d'Etudes de Métallurgie Physique et de Physique des Matériaux, UMR CNRS 5510, INSA de Lyon, Bâtiment B. Pascal, 7 Avenue Jean Capelle, 69621 Villeurbanne Cedex, France. Agnes.Bogner@insa-lyon.fr
Micron (Oxford, England : 1993)
|September 23, 2006
Summary
Wet scanning transmission electron microscopy (STEM) enables high-resolution imaging of nano-objects in liquids. Advances in environmental scanning electron microscopy (ESEM) and electron sources were crucial for this breakthrough.
Area of Science:
- Materials Science
- Nanotechnology
- Microscopy
Background:
- Environmental scanning electron microscopy (ESEM) has been enhanced to enable new imaging capabilities.
- Traditional scanning electron microscopy (SEM) is limited in observing samples in liquid environments.
Observation:
- A novel imaging mode, wet scanning transmission electron microscopy (wet-STEM), allows direct observation of nano-objects in liquid.
- This technique operates in transmission mode within an environmental SEM (wet-STEM-in-SEM).
Findings:
- Wet-STEM achieves nanometer resolution with a good signal-to-noise ratio for liquid-suspended nano-objects.
- Key advancements include high-brightness electron sources and improvements in ESEM technology.
Implications:
- Wet-STEM expands the application scope of SEM as an accessible, high-resolution imaging tool.
- This technique facilitates the study of a wider range of samples, particularly those in liquid phases.
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