Materials Analysis

This overview covers the major teclnhques used in materials analysis with MeV ion beams Rutherford backscattering, chaimelling, 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]. 

Tesmer J R and Nastasi M (eds) 1995 Flandbook of Modem Ion Beam Materials Analysis (Pittsburgh, PA Materials Research Society)... 

Feldman L C, Mayer J W and Picraux S T 1982 Materials Analysis by Ion Channelling (New York Academic)... 

Cox R P, Leavitt J A and Mointyre L C Jr 1995 Non-Rutherford eiastio baoksoattering oross seotions Handbook of Modem Ion Beam Materials Analysis ed J R Tesmer and M Nastasi (Pittsburgh, PA Materiais Researoh Sooiety) oh A7, p 481... 

Breese M B H, Jamieson D N and King P J C 1996 Materials Analysis with a Nuclear Mioroprobe (New York Wiiey)... 

In the x-ray portion of the spectmm, scientific CCDs have been utilized as imaging spectrometers for astronomical mapping of the sun (45), galactic diffuse x-ray background (46), and other x-ray sources. Additionally, scientific CCDs designed for x-ray detection are also used in the fields of x-ray diffraction, materials analysis, medicine, and dentistry. CCD focal planes designed for infrared photon detection have also been demonstrated in InSb (47) and HgCdTe (48) but are not available commercially. 

The most important general test methods are issued as ASTM Test Methods and are periodically updated by the Polyurethane Raw Materials Analysis Committee (PURMAC) of the Society for the Plastics Industry (SPI). PURMAC has collected all pertinent analytical methods in a manual (271). 

Raw material analysis (indicate liquid chromatography or gas chromatography)... 

Computers will be integrated more and more into commercial SEMs and there is an enormous potential for the growth of computer supported applications. At the same time, related instruments will be developed and extended, such as the scanning ion microscope, which uses liquid-metal ion sources to produce finely focused ion beams that can produce SEs and secondary ions for image generation. The contrast mechanisms that are exhibited in these instruments can provide new insights into materials analysis. 

There are thousands of commercial spectrometers in use today in materials analysis, chemistry, and ph) ics laboratories. The largest concentrations are in the US and Japan. They are used in universities, the semiconductor and computer industries, and the oil, chemical, metallurgical, and pharmaceutical industries. 

PracticalSu face Analysts, edited by D. Briggs and M. P. Seah, published by J. Wiley Handbook of XPS and UPS, edited by D. Briggs. Both contain extensive discussion on use of XPS for surface and material analysis. 

As stated earlier, the major use of UPS is not for materials analysis purposes but for electronic structure studies. There are analysis capabilities, however. We will consider these in two parts those involving the electron valence energy levels and those involving low-lying core levels accessible to UPS photon energies (including synchrotron sources). Then we will answer the question why use UPS if XPS is available ... 

In principle all the X-ray emission methods can give chemical state information from small shifts and line shape changes (cf, XPS and AES in Chapter 5). Though done for molecular studies to derive electronic structure information, this type of work is rarely done for materials analysis. The reasons are the instrumental resolution of commercial systems is not adequate and the emission lines routinely used for elemental analysis are often not those most useftil for chemical shift meas-ure-ments. The latter generally involve shallower levels (narrower natural line widths), meaning longer wavelength (softer) X-ray emission. 

Photoluminescence is a well-established and widely practiced tool for materials analysis. In the context of surface and microanalysis, PL is applied mostly qualitatively or semiquantitatively to exploit the correlation between the structure and composition of a material system and its electronic states and their lifetimes, and to identify the presence and type of trace chemicals, impurities, and defects. 

Early work in ellipsometry focused on improving the technique, whereas attention now emphasizes applications to materials analysis. New uses continue to be found however, ellipsometry traditionally has been used to determine film thicknesses (in the rang 1-1000 nm), as well as optical constants. " Common systems are oxide and nitride films on silicon v ers, dielectric films deposited on optical sur ces, and multilayer semiconductor strucmres. 

Manual null ellipsometry is accurate but infrequently done, due to the length of time needed to acquire sufficient data for any meaningffil materials analysis. Automated null ellipsometers are used, for example, in the infrared, but are still slow. Numerous versions of last automated ellipsometers have been built. Examples... 

J. R. fiiid and J. S. Williams. Ion Beams for Materials Analysis. Academic Press, Australia, 1989. Chapter 3 provides an overview of RfiS, while Chapter 6 reviews channeling techniques. This book also reviews NRA PIXE, SIMS, and other related ion-beam analyses. 

Ion Beam Handbook for Material Analysis. (J. W. Mayer and E. Rimini, eds.) Academic Press, New York, 1977. This book provides useful tabular and graphic data for RBS, channeling, PIXE, and NRA. 

J. E. E. Baglin and J. S. Williams. High Energy Ion Scattering Spectrometry. In Ion Beamsfor Materials Analysis. Q. R. Bird and J. S. Williams, eds.) Academic Press, Sydney, 1989. 

L. C. Feldman, J. W. Mayer, and S. T. Picraux. Materials Analysis by Ion Channeling. Academic, New York, 1982. General introduction to ion scattering. 

Obtaining the aqueous solution to analyze is often a challenge in materials analysis. Thin films usually can be dissolved by acids without dissolving the underlying substrate, however sometimes this is difficult. A film can also be oxidized and the oxide dissolved. Temperatures involved in this procedure are sometimes quite elevated so care must be taken to maintain sample integrity. The chemistry of the sample must be kept in mind so that the limits of the analysis are known. 

Since the recognition in 1936 of the wave nature of neutrons and the subsequent demonstration of the diffraction of neutrons by a crystalline material, the development of neutron diffraction as a useful analytical tool has been inevitable. The initial growth period of this field was slow due to the unavailability of neutron sources (nuclear reactors) and the low neutron flux available at existing reactors. Within the last decade, however, increases in the number and type of neutron sources, increased flux, and improved detection schemes have placed this technique firmly in the mainstream of materials analysis. 

J. A. Leavitt, L. C. McIntyre, M. R. Weller in J. R. Tesmer, M. Nastasi (eds.) Handbook of Modem Ion Beam Materials Analysis, Materials Research Society, Pittsburgh... 

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