LEIS primary ion source:
- Operation with noble gases, He+, Ne+ and Ar+.
- Adjustable ion currents, 1pA – 100 nA.
- Beam energies from 1 keV to 8 keV
- Spot size < 30 µm. Can be rastered over an area up to 4 x 4 mm.
- Pulsed ion beam operation for TOF filtered measurements.
The low energy sputtering source:
- High current ion optical column used for ultra-low energy sputtering in dual beam depth profiling.
- Operation with Ar+.
- Adjustable ion currents, typically up to 600 nA.
- Beam energies typically from 0.2 keV to 2 keV
Analyser
- Double toroidal analyser offers 3,000× increase in sensitivity compared to conventional LEIS.
- TOF filter improves detection limit in the low energy range.
- Self-adjusting charge compensation source enables analysis of insulators.
Imaging:
- Secondary ion and secondary electron detector for imaging.
- Rastering of focussed ion beams allows evaluation of the chemical information with respect to the position on the sample surface, generating images of the lateral distribution of individual surface materials.
Sample mounting and manipulation
- A 5-Axis sample stage is used. Full automation and computer control of all axes.
- Carousel for mounting up to 8 samples in chamber.
- Typical sample size up to 12 x 12mm. Holders for larger samples and powder samples are also available.
- Load lock entry for fast loading into UHV system. ~60s to load sample.
- Sample holders for in-situ heating up to 900°C in UHV.
- Analysis chamber base pressure < 1x10-10 mbar.
In-situ sample processing
- Equipped with a plasma source allowing the treatment of samples with low energy atomic hydrogen or oxygen. Atomic beam has a diameter of more than 1 cm². This can be used for in-situ chemical sample cleaning and controlled reduction/oxidation of samples.
- In-situ (in vacuo) processing chamber to enable the simulation of various processing or environmental conditions. DN25KF outlet, DN16CF input flanges, viewports. Users will be able to connect gases, pumps, sensors and other equipment to the reaction cell to simulate a range of manufacturing processes.
LEIS operating modes
- Surface spectroscopy
- Very sensitive
- Highly quantitative
- Negligible ‘matrix effect’
- Static depth profiling
- Non-destructive
- 10nm depth
- Quantitative
- Sputter depth profiling (dual beam mode)
- Destructive
- Up to ~100nm depth
- Much finer depth resolution than XPS and Tof-SIMS
- Surface ‘imaging’
- Ion beam scanning & also stage scanning
- Chemical mapping
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