Rutherford Backscattering Spectrometry (RBS)
Rutherford Backscattering Spectrometry (RBS) is a technique used for non-destructive testing of thin-film materials. This technique is widely utilized for depth profile analysis, near-surface layer analysis and compositional analysis of thin films. The results obtained from the analysis can also be utilized to examine the quality of single-crystal substrate. Thin film samples less than 1μm thick can also be subjected to depth profiling using this technique.
In the RBS method high energy helium ions (0.5–4 MeV) are applied directly onto the samples, which are repelled by the positively charged nucleus atoms in the specimen. The energy distribution and yield of backscattered ions is measured by a solid-state detector and then the compositional analysis and depth profiling are performed by the obtained information.
RBS technique is used to obtain the information regarding shape, size and orientation of various substances. Since the cross section of scattering and the energy of backscattered ions can be calculated theoretically, the elemental composition and its depth profile can be evaluated. By using the channelling measurement the damage of the crystal can be determined.
MaTestLabs has the best network of laboratories that can perform RBS tests for its clients based in the USA. These well-equipped testing labs perform routine tests as well as the custom tests according to the specific requirements of clients.
Applications of Rutherford Backscattering Spectrometry (RBS)
- Compositional analysis of thin film as well as stoichiometric ratio and thickness determination
- Measurement of film density with unknown thickness
- Near-surface layer analysis of thin film
- Determination of the metal ions concentration diffused in polymers
- Areal concentrations (atoms/cm2) analysis
- Colloidal nanocrystals determination to determine compositional changes during cation-exchange reactions
- Composition analysis of reverse osmosis membranes
- Determination of the accurate elemental composition and density
Advantages of Rutherford Backscattering Spectrometry (RBS)
- Quantification without the use of reference standards
- Non-destructive method
- High depth resolution of several nanometers (nm)
- High sensitivity in parts per million (ppm) for heavy elements
- Conductive and insulating sample can be characterized
Limitations of Rutherford Backscattering Spectrometry (RBS)
- Quantitative analysis of hydrogen is done by Less sensitive for light elements- elastic recoil detection analysis (ERDA) whereas the light elements from Li-Ne characterized by nuclear reaction analysis (NRA)
- Chemical structure of the sample cannot be determined
- Limited depth profile to top ~1 μm of samples
- Vacuum compatibility of samples is required
- The mass resolution or ability to differentiate between elements is very low for high
- Atomic number elements
