Scanning ion microscopy with low energy lithium ions
Kevin A Twedt1, Lei Chen2, Jabez J McClelland2
1Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA; Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA.
Ultramicroscopy
|April 23, 2014
Summary
We developed a new scanning ion microscope using laser-cooled lithium atoms. This low-energy ion microscope offers surface-sensitive analysis for applications like etching processes in nano-imprint lithography.
Area of Science:
- Materials Science
- Surface Science
- Nanotechnology
Background:
- Conventional ion microscopes (He-ion, Ga-FIB) operate at higher energies.
- Higher beam energies can lead to larger interaction volumes and reduced surface sensitivity.
Purpose of the Study:
- To develop a scanning ion microscope utilizing low-energy, laser-cooled lithium ions.
- To demonstrate the advantages of low-energy ion microscopy for surface analysis.
Main Methods:
- Utilized a photoionization source with laser-cooled lithium atoms.
- Developed a scanning ion microscope with probe sizes of tens of nanometers.
- Operated at beam energies from 500 eV to 5 keV.
Main Results:
- Achieved probe sizes of a few tens of nanometers.
- Demonstrated advantages of low-energy beams for backscattered ion detection.
- Enabled surface-sensitive composition analysis due to decreased interaction volume.
Conclusions:
- Low-energy ion microscopy offers unique advantages for surface analysis.
- The developed lithium ion microscope is suitable for non-destructive imaging of thin film removal during etching.
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