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Lensfree On-chip Tomographic Microscopy Employing Multi-angle Illumination and Pixel Super-resolution
Published on: August 16, 2012
A novel in-lens detector for electrostatic scanning LEEM mini-column
Frank1, Mullerova, el Gomati MM
1Institute of Scientific Instruments, Academy of Sciences of the Czech Republic, Brno, Czech Republic. ludek@isibrno.cz
Ultramicroscopy
|September 22, 2000
Summary
A new in-lens electron detector offers superior efficiency for very slow electrons, enabling low-energy imaging. This advancement surpasses conventional scanning electron microscope detectors for secondary electrons.
Area of Science:
- Physics
- Materials Science
- Electron Microscopy
Background:
- Conventional scanning electron microscopes (SEM) struggle with imaging very slow electrons.
- Auger electron microanalysis requires high sensitivity for low-energy electron detection.
Purpose of the Study:
- To describe a novel in-lens detector for very slow electrons.
- To evaluate the efficiency of this new detector design.
Main Methods:
- Integration of an in-lens detector into a coaxial column for a Cylindrical Mirror Analyser.
- Formation of a cathode lens for low-energy scanned imaging.
- Utilizing a micro-channel-plate based detector for signal electrons.
Main Results:
- The detector demonstrated high acceptance ratios: 0.86 for 1 eV and 0.985 for 10 eV electrons.
- Conversion efficiencies of 0.35 (1 eV) and 0.31 (10 eV) surpass conventional SEM detectors.
- Successful acquisition of micrographs at energies as low as a few eV.
Conclusions:
- The novel in-lens detector provides superior performance for detecting very slow electrons.
- This technology enables advanced low-energy imaging capabilities in electron microscopy.
- The detector is suitable for applications like Auger electron microanalysis requiring high sensitivity.
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