Rutherford backscattering analysis technique

Taglauer E 1997 Low-energy Ion scattering and Rutherford backscattering Surface Analysis The Principal Techniques ed J C VIckerman (Chichester Wiley) pp 215-66... 

Within the last 5—10 years PIXE, using protons and helium ions, has matured into a well-developed analysis technique with a variety of modes of operation. PIXE can provide quantitative, nondestructive, and fast analysis of essentially all elements. It is an ideal complement to other techniques (e.g., Rutherford backscattering) that are based on the spectroscopy of particles emitted during the interaction of MeV ion beams with the surface regions of materials, because... 

The use of nuclear techniques allows the determination of C, N, H, O, and heavier contaminants relative fractions with great accuracy, and of the elements depth profile with moderate resolution (typically 10 nm). Rutherford backscattering spectroscopy (RBS) of light ions (like alpha particles) is used for the determination of carbon and heavier elements. Hydrogen contents are measured by forward scattering of protons by incident alpha particles (ERDA) elastic recoil detection analysis [44,47]. 

In addition to the techniques already discussed, aspects of MC formation in LB films have been investigated by Rutherford backscattering (RBS) (65) and fluorimetry (17,49,50.76,79,81,83,84). The results from the RBS analysis of H2S-exposed CdAr films provided evidence for the formation of spheroidal CdS particles. Investigations of the fluorescence properties of MC particles in LB films are discussed later. 

Rutherford Backscattering Spectrometry (RBS) is a non-destructive (sub)-surface analysis technique for solid systems. In principle atomic composition and depth distribution can be obtained for a sub-surface layer of a few microns. 

Rutherford Backscattering Spectroscopy (RBS) is an established technique for analysis of inorganic materials. Recently, several applications of RBS on polymer films have been reported however, the effect of ion beams on these surfaces has not been well documented. RBS has been used to determine fluorine distribution in polymers. Since ion beam irradiation of polymers can induce chemical changes, instrumental parameters need to be optimized to minimize damage. 

The application of ion beam analysis techniques to determine pore size and pore volume or density of thin silica gel layers was first described by Armitage and co-workers [114]. These techniques are non-destructive, sensitive and ideally suited for the analysis of thin porous films such as membrane layers (dense support is needed for backscattering). However, apart from a more recent report on ion-beam analysis of sol-gel films [115] using Rutherford backscattering and forward recoil spectrometry, ion beam techniques have not been developed further despite their potential for membrane characterisation. This is probably due to the limited availability of ion beam sources, such as charged particles accelerators. 

The remaining work discusses two techniques in thin film analysis, Rutherford backscattering spectrometry (RBS) and X-ray diffractrometry with emphasis on strain measurements. Rutherford backscattering spectrometry is illustrated with analysis of silicide formation as an example of thin film reactions. Silicon-germanium-carbon films serve as an example of strain calculations. 

SIMS Is more sensitive than the other common surface or Interface analysis techniques of Auger X-ray Photoelectron Spectroscopy Rutherford BackscatterIng Spectroscopy or Energy Dispersive X-ray Analysis. Detection limits and background signal levels for a large number of semiconductor materials have been reported under typical operating conditions (Ji). Table I lists the detection limits for a number of dopants used In semiconductors obtained under optimized conditions. 

Particle- or proton-induced. X-ray emission (PIXE) is another modern powerful yet non-destructive elemental analysis technique used to determine the elemental make-up of a sample material. When a material is exposed to a particle or proton beam, atomic interactions occur that give off electromagnetic radiation of wavelengths in the X-ray part of the electromagnetic spectrum characteristic of an element. Three different types of spectra can be collected from a PIXE experiment an X-ray emission spectrum, a Rutherford (proton) backscattering spectrum and a proton transmission spectrum. 

This overview covers the major techniques used in materials analysis with MeV ion beams Rutherford backscattering, channelling, resonance scattering, forward recoil scattering, PIXE and microbeams. We have not covered nuclear reaction analysis (NRA), because it applies to special incident-ion-target-atom combinations and is a topic of its own [1, 2]. 

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