New beam line for time-of-flight medium energy ion scattering with large area position sensitive detector
M K Linnarsson1, A Hallén, J Åström
1KTH Royal Institute of Technology, School of Information and Communication Technology, Integrated Circuits and Devices, P.O. Box E229, SE-16440 Kista-Stockhom, Sweden. marga@kth.se
The Review of Scientific Instruments
|October 2, 2012
Summary
A new Medium Energy Ion Mass Scattering (MEIS) system utilizing time-of-flight technology has been developed. This advanced system achieves nanometer depth resolution and mass resolution for isotope analysis, benefiting semiconductor research.
Area of Science:
- Materials Science
- Physics
- Analytical Chemistry
Background:
- Development of advanced analytical techniques is crucial for materials characterization.
- Existing methods may lack the required depth and mass resolution for nanoscale analysis.
Purpose of the Study:
- To design and implement a novel Medium Energy Ion Mass Scattering (MEIS) system.
- To evaluate the performance of the new MEIS system for depth profiling and mass spectrometry.
Main Methods:
- A time-of-flight (ToF) based MEIS system was engineered with a 4 MHz function generator for beam chopping.
- Utilized a 6-axis goniometer and a time-resolved, position-sensitive detector for ion scattering analysis.
- Tested with probing ions including H+, He+, and B+.
Main Results:
- Achieved nanometer-level depth resolution, capable of resolving 1-2 nm Pt layers.
- Demonstrated mass resolution for nearby isotopes, exemplified by Ga isotopes in GaAs.
- Obtained direct imaging of crystal channel blocking patterns in 4H-SiC.
Conclusions:
- The new ToF-MEIS system offers high performance for semiconductor and thin film analysis.
- The system is suitable for sub-nanometer depth profiling in device development.
- It will also support fundamental studies on stopping cross sections.
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