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Updated: Aug 5, 2026
08:04
Preparation and Observation of Thick Biological Samples by Scanning Transmission Electron Tomography
Published on: March 12, 2017
Sub-Angstrom high-resolution transmission electron microscopy at 300 keV
M A O'Keefe1, C J Hetherington, Y C Wang
1Materials Science Division, National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. maok@lbl.gov
Ultramicroscopy
|January 5, 2002
Summary
The National Center for Electron Microscopy achieved sub-Angstrom resolution using the one-Angstrom microscope (OAM). This breakthrough in transmission electron microscopy offers unprecedented detail for materials science research.
Area of Science:
- Materials Science
- Physics
- Microscopy
Background:
- Advanced transmission electron microscopy (TEM) is crucial for materials characterization.
- Existing TEM resolution limits, like Scherzer resolution, can be overcome with enhanced hardware and software.
- The National Center for Electron Microscopy (NCEM) has pursued higher resolution imaging capabilities.
Purpose of the Study:
- To achieve sub-Angstrom resolution in transmission electron microscopy.
- To demonstrate the capabilities of the one-Angstrom microscope (OAM) project.
- To provide materials scientists with enhanced imaging resolution.
Main Methods:
- Utilized enhanced hardware and software developed within the Ultramicroscopy Brite-Euram project.
- Employed image reconstruction techniques, including off-axis holograms and focal series of underfocused images.
- Leveraged the higher information limit of a field emission gun transmission electron microscope (FEG-TEM).
Main Results:
- Achieved a resolution of 0.89 Angstroms using the OAM on a [1 1 0] diamond test specimen.
- Measured coherence parameters predicted an information limit of 0.78 Angstroms.
- Demonstrated effective image reconstruction to surpass the Scherzer resolution limit.
Conclusions:
- Sub-Angstrom resolution in transmission electron microscopy is achievable.
- The OAM project successfully enhanced TEM capabilities at NCEM.
- Advanced reconstruction methods significantly improve the effective resolution of TEM imaging.
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