Ion beam analysis
Ion beam analysis ("IBA") is an important family of modern analytical techniques involving the use of MeV ion beams to probe the composition and obtain elemental depth profiles in the near-surface layer of solids. All IBA methods are highly sensitive and allow the detection of elements in the sub-monolayer range. The depth resolution is typically in the range of a few nanometers to a few ten nanometers. Atomic depth resolution can be achieved, but requires special equipment. The analyzed depth ranges from a few ten nanometers to a few ten micrometers. IBA methods are always quantitative with an accuracy of a few percent. Channeling allows to determine the depth profile of damage in single crystals.
- RBS: Rutherford backscattering is sensitive to heavy elements in a light matrix
- EBS: Elastic (non-Rutherford) backscattering spectrometry can be sensitive even to light elements in a heavy matrix. The term EBS is used when the incident particle is going so fast that it exceeds the "Coulomb barrier" of the target nucleus, which therefore cannot be treated by Rutherford's approximation of a point charge. In this case Schrödinger's equation should be solved to obtain the scattering cross-section (see http://www-nds.iaea.org/sigmacalc/).
- ERD: Elastic recoil detection is sensitive to light elements in a heavy matrix
- PIXE: Particle induced X-ray emission gives the trace and minor elemental composition
- NRA: Nuclear reaction analysis is sensitive to particular isotopes
- Channelling: The fast ion beam can be aligned accurately with major axes of single crystals; then the strings of atoms "shadow" each other and the backscattering yield falls dramatically. Any atoms off their lattice sites will give visible extra scattering. Thus damage to the crystal is visible, and point defects (interstitials) can even be distinguished from dislocations.
The quantitative evaluation of IBA methods requires the use of specialized simulation and data analysis software. SIMNRA and DataFurnace are popular programs for the analysis of RBS, ERD and NRA, while GUPIX is popular for PIXE.
IBA is an area of active research. The last major Nuclear Microbeam conference in Debrecen (Hungary) was published in NIMB 267(12-13).
- Biennial scientific conference devoted to IBA: there was one in Hyderabad in September 2007. The latest in this series (19th) was held in Cambridge in September 2009 (hosted by the ion beam group in Guildford) and the next (20th) will be in Itapema (Brazil) in 2011 (hosted by the ion beam group in Porto Alegre).
- Triennial European scientific conference ECAART (European Conference on Accelerators in Applied Research and Technology): the latest was in: Florence, September 2007. The next in this series (10th) will be held in Athens, Greece, September 2010.
- Trienniel scientific conference devoted to PIXE: the latest was in Mexico in 2007, and the next will be in Guildford in 2010.
- "Nuclear Instruments and Methods": The international peer reviewed scientific journal largely devoted to IBA developments and applications
- SIMNRA program for the simulation and analysis of RBS, EBS, ERD and NRA spectra
- DataFurnace program for the simulation and analysis (self-consistent fitting) of multiple PIXE, RBS, EBS, ERD, NRA, PIGE, NRP, NDP spectra
- NDF free version of NDF (the calculation engine underlying DataFurnace) for the simulation of IBA spectra
- GUPIX program for the simulation and analysis of PIXE spectra
- Software for PIXE analysis Intercomparison of PIXE spectrometry software packages
- The Acceleratorer List of IBA related conferences and facilities
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