Rutherford backscattering spectrum

Figure 5. Rutherford backscattering spectra (RBS) of films 1 (a) and 2 (b) deposited on Si wafers.

Fig. 5 Rutherford backscattering spectra of a 200-nm Ni thin film on a silicon substrate before and after annealing. (View this art in color at WWW. dekker. com.)...

Figure 7 Rutherford backscattering spectra from a Ag(111) crystal for ion incidence along a <110> direction. The four spectra are for increasing coverages of Au (bottom to top). (Reproduced with permission from Culbertsen RJ, Feldman LC, Silverman PL, and Boehm H (1981) Epitaxy of Au on Ag (111) studied with high-energy ions scattering. Physical Review Letters 47 657 American Physical Society.)...

Channeling Rutherford backscattering spectra (RBS) of a crystalline Si wafer that was implanted by He ions (10 ion/cm units) then annealed. Virgin and random spectra are also included (Manuaba et al. 2001)... 

RUMP Doolittle LR (1985) Algorithms for the Rapid Simulation of Rutherford Backscattering Spectra Nucl. Instrum. Methods in Phys. Res. B9 344... 

That these ideas have some merit is indicated by the work of Hart, Dunlap, and Marsh . These investigators deposited a fraction of a monolayer of copper onto a silicon wafer and then monitored the position and concentration of the copper using Rutherford backscattering. After deposition, the copper, which was then located on the immediate surface, was bombarded with 20 keV Ne ions to a fluence sufficient to sputter 90 A of Si from the surface. The Rutherford backscattering spectrum, which was taken after this bombardment, showed that the copper was uniformly distributed to a depth of 600 A which corresponds roughly to the projected range of the Ne" " ions, i.e., the depth of the altered layer was approximately equal to the projected range of the Ne. 

Figure 1. A Rutherford backscattering spectrum for a thin (40/ig/cm2) MoSt sputter-deposited film. Conditions 4He ions normally incident at 3.0 MeV, and scattered ions detected at a 135° angle by a surface-barrier diode detector. Note the scale factor for other than the Mo peak and the Si substrate. The sample layer configuration is indicated at the upper left.

Figure 2. A partial Rutherford backscattering spectrum for a relatively thick (430jxg/cm2) sputter-deposited solid lubricant thin film with conditions as in Fig. 1.

An example of the change in composition of a silicide layer is shown in Fig. 12.5 for PtSi that was sputtered with 20keV argon ions and then analyzed with 2 MeV 4He ions. The Rutherford backscattering spectrum shows an enrichment of the Pt concentration in the surface region. The ratio of Pt/Si increased from the value of unity associated with that of the bulk to a value near two in the surface region. The increased concentration of Pt at the surface occurs because the partial... 

The essentially non-destructive nature of Rutherford backscattering spectrometry, combined with the its ability to provide both compositional and depth information, makes it an ideal analysis tool to study thin-film, solid-state reactions. In particular, the non-destructive nature allows one to perform in situ RBS, thereby characterizing both the composition and thickness of formed layers, without damaging the sample. Since only about two minutes of irradiation is needed to acquire a Rutherford backscattering spectrum, this may be done continuously to provide a real-time analysis of the reaction [6]. 

Figure 1 Rutherford backscattering spectrum ( = 2MeV, 0lab = 14O) from an Si crystal with thin layers of Cr (3x 10 atoms cm and Au (8 x 10 atoms cm evaporated onto the surface. The continuum at low energies is due to ions backscat-tered from Si after penetration into the bulk. The energy of such ions can be related to the scattering depth.

Rutherford backscattering spectrometry spect A method of determining the concentrations of various elements as a function of depth beneath the surface of a sample, by measuring the energy spectrum of ions which are backscattered out of a beam directed at the surface. roth-or-ford bak,skad-3-rir spek tram-o-tre rutherfordium chem A chemical element, symbolized Rf, atomic number 104, a synthetic element the first element beyond the actinide series, and the twelfth transuranium element., r3lh 3t fdr-de-3m ... 

Figure 13.8 Rutherford backscattering for 2.0 MeV 4He ions incident on a Si (Co) sample. Dots represent the experimental data while the solid line is a simulated spectrum. Scattering angle = 170°, with 0i = 02 = 5°. [From Saarilahti and Rauhala (1992).]...

It was also revealed that Tm3+ ions doped in GaN QDs embedded in AIN layer are partially located in the GaN QDs and partially at the GaN/AIN interface by means of structural characterizations such as EXAFS and Rutherford backscattering spectroscopy (RBS) (Andreev et al., 2005a). Consistently, CL spectra (fig. 21) can be well interpreted by assuming that Tm3+ is located inside QDs but also in the surrounding AIN spacer. (1) Intense sharp emission lines from the 1le, JD2, and1G4 levels of Tm3+ in the blue-green region (450-550 nm), which were absent for the Tm-doped GaN thick layer, were observed in the PL spectrum (fig. 21b). This provides clear evidence for Tm3+ ions located in QDs. (2) Compared to the PL spectrum, the CL spectrum of the same GaN Tm QD sample (fig. 21c) shows additional sharp lines which coincide with those of the CL spectrum of AIN (fig. 2Id). Thus it confirms that Tm3+ ions are also present in the AIN barrier layer. 

Fig. 4.14 Schematic representation of Rutherford backscattering (RBS). (a) The incident ions are directed such that they either scatter back from surface atoms or channel deeply into the crystal, (b) The ions scatter back from target atoms throughout the outer micrometers and suffer inelastic losses, causing the energy of the backscattered ions to tail to zero, (c) Scattering from the heavy outer layer gives a sharp peak separated from the spectrum of the substrate as in (b).

Glancing angle (a=80 ) Rutherford backscattering spectrometry (RBS) with a 2.0 MeV He" beam was used to obtain the depth-resolved elemental composition of the films. In order to obtain sufficient counting statistics, and at the same time minimize beam-induced damage, each spectrum was accumulated from 20 different spots on the sample. The He ion beam dose was kept below 1 C/cm per spot. Spectral simulation was performed using the computer code RUMP (14). 

Figure 7.40. Rutherford backscattering (RBS) spectrum of a LiNiV04 film (thickness of 240( 5) A) on a carbon substrate. The open squares represent the experimental RBS data, and the continuous fine is the simulated data. Reproduced with permission from Reddy, M. V. Pecquenard, B. Vinatier, R Levasseur, A. J. Phys. Chem. B 2006,110,4301. Copyright 2006 American Chemical Society.

Fig. 2.13. Result of a Kirkendall marker experiment carried out by Rutherford backscattering spectroscopy. The upper part shows the marker shifts (A m and A ) for the tungsten marker and the Zr edge from the backscattering spectrum. The lower part compares the experimental data with the expected behavior of the marker shift when only one species moves (dashed lines). Within experimental error, it is found that only Ni moves (see [2.46] for details)...

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. 

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