Rutherford Backscattering Spectrometry – RBS

Rutherford Backscattering Spectrometry (RBS) is a widely used ion scattering analytical technique used to determine the elemental composition profile and depth of thin films. RBS is a non-destructive technique frequently used in a testing lab for thin-film semiconductor material stacks and for determining the concentration of trace elements heavier than the major constituents of the substrate.

Rutherford Backscattering Spectrometry

Rutherford Backscattering Spectrometry (RBS) is a non-destructive elemental analysis technique frequently used for thin-film semiconductor material stacks. It is frequently used for quantitative compositional analysis of a sample, depth profiling of individual elements, and near-surface layer analysis of the samples. This information can be used to determine the quality of single-crystal substrate samples as well. Depth profiling characterization of films can be performed up to less than 1μm thick samples.

RBS test uses beams of high-energy helium ions (typically 0.5–4 MeV) directed onto a sample, which are repelled by the positively charged nucleus of atoms in the specimen. A solid-state detector measures the energy distribution and yield of backscattered ions from the sample which is used to obtain the elemental composition and depth profile.

Our well-equipped testing labs perform RBS test for our clients based in the USA and other parts of the world. We at Infinita Lab perform not only routine tests, but also custom tests designed in our laboratory as per the client’s specific requirements.

Rutherford Backscattering Spectrometry (RBS) Common Uses

• Determination of composition, thickness, and stoichiometric ratio of thin films
• Quantification of the film density (when the thickness is known)
• Determination of near-surface crystallinity of the sample
• The concentration profiles of metal ions diffused in polymers
• Determine areal concentrations (atoms/cm²)
• Characterization of colloidal nanocrystals to quantify compositional changes during cation-exchange reactions
• The composition analysis of reverse osmosis membranes in laboratory

Rutherford Backscattering Spectrometry (RBS) Advantages

• Provides quantitative analysis of a sample without the need for reference standards
• Non-destructive technique
• The good depth resolution of the order of several nanometers (nm)
• Good sensitivity for heavy elements in the order of parts per million (ppm)
• Analysis of both conductive and insulating samples is possible

Rutherford Backscattering Spectrometry (RBS) Limitations

• Less sensitive for light elements- elastic recoil detection analysis (ERDA) is used for the quantitative determination of hydrogen, while nuclear reaction analysis (NRA) is used for the determination of light elements from Li-Ne
• RBS can not determine the chemical structure of the sample
• Useful depth profile limited to top ~1μm of samples
• The sample should be compatible with vacuum

Industries served in the USA and other countries

• Semiconductors
• Advanced Materials
• Coatings, Thin Films, and Membranes
• Laboratories
• EAG Laboratories, Inc.
• Amethyst Analytical
• Cerium Laboratories, LLC
• Materials Research Laboratory, University of Illinois

More Details

• Working principle of RBS
• Advantages of RBS
• Limitations of RBS