Secondary ion mass

SIMS Secondary-ion mass spectroscopy [106, 166-168] (L-SIMS liquids) [169, 170] Ionized surface atoms are ejected by impact of -1 keV ions and analyzed by mass spectroscopy Surface composition... 

Ions are also used to initiate secondary ion mass spectrometry (SIMS) [ ], as described in section BI.25.3. In SIMS, the ions sputtered from the surface are measured with a mass spectrometer. SIMS provides an accurate measure of the surface composition with extremely good sensitivity. SIMS can be collected in the static mode in which the surface is only minimally disrupted, or in the dynamic mode in which material is removed so that the composition can be detemiined as a fiinction of depth below the surface. SIMS has also been used along with a shadow and blocking cone analysis as a probe of surface structure [70]. 

Benninghoven A, Rudenauer F G and Werner FI W 1987 Secondary ion Mass Spectrometry Basic Concepts, instrumentai Aspects, Appiications, and Trends (New York Wiley)... 

Chang C-C and Winograd N 1989 Shadow-cone-enhanced secondary-ion mass-spectrometry studies of Ag(110) Rhys. Rev. B 39 3467... 

SIMS Secondary Ion mass spectroscopy A beam of low-energy Ions Impinges on a surface, penetrates the sample and loses energy In a series of Inelastic collisions with the target atoms leading to emission of secondary Ions. Surface composition, reaction mechanism, depth profiles... 

Secondary ion mass spectrometry (SIMS) is by far the most sensitive surface teclmique, but also the most difficult one to quantify. SIMS is very popular in materials research for making concentration depth profiles and chemical maps of the surface. For a more extensive treatment of SIMS the reader is referred to [3] and [14. 15 and 16]. The principle of SIMS is conceptually simple When a surface is exposed to a beam of ions... 

Vickerman J C, Brown A and Reed N M (eds) 1989 Secondary Ion Mass Spectrometry, Principles and Applications (Oxford Clarendon)... 

Briggs D, Brown A and Vickerman J C 1989 Handbook of Static Secondary Ion Mass Spectrometry (Chichester Wiley)... 

Barish E L, Vitkavage D J and Mayer T M 1985 Sputtering of chlorinated silicon surfaces studied by secondary ion mass spectrometry and ion scattering spectroscopy J. AppL Phys. 57 1336-42... 

Fast-Atom Bombardment (FAB) and Liquid-Phase Secondary Ion Mass Spectrometry (LSIMS) Ionization... 

A big step forward came with the discovery that bombardment of a liquid target surface by abeam of fast atoms caused continuous desorption of ions that were characteristic of the liquid. Where this liquid consisted of a sample substance dissolved in a solvent of low volatility (a matrix), both positive and negative molecular or quasi-molecular ions characteristic of the sample were produced. The process quickly became known by the acronym FAB (fast-atom bombardment) and for its then-fabulous results on substances that had hitherto proved intractable. Later, it was found that a primary incident beam of fast ions could be used instead, and a more generally descriptive term, LSIMS (liquid secondary ion mass spectrometry) has come into use. However, note that purists still regard and refer to both FAB and LSIMS as simply facets of the original SIMS. In practice, any of the acronyms can be used, but FAB and LSIMS are more descriptive when referring to the primary atom or ion beam. 

The basic principles of fast-atom bombardment (FAB) and liquid-phase secondary ion mass spectrometry (LSIMS) are discussed only briefly here because a fuller description appears in Chapter 4. This chapter focuses on the use of FAB/LSIMS as part of an interface between a liquid chromatograph (LC) and a mass spectrometer (MS), although some theory is presented. 

FAB has evolved, and fast atoms are being replaced by fast ions, such as cesium (Cs+). This variation is called liquid secondary ion mass spectrometry (LSIMS) because the sample solution affords the secondary ion beam while the bombarding ions constitute the primary beam. Spectra... 

Confusingly, FAB is sometimes called secondary ion mass spectrometry (SIMS), the secondary referring to the nature of the process (primary bombardment, secondary emission), but see next item. 

Historically, the term SIMS was developed for bombardment of solid surfaces with ions, so, for greater descriptive precision, the name liquid secondary ion mass spectrometry (LSIMS) is better and can be used synonymously with FAB,... 

The term liquid secondary ion mass spectrometry (LSIMS) is sometimes used synonymously with FAB and is preferred by some as being more descriptive, since FAB could apply to bombardment of solid or liquid surfaces and does not indicate the types of secondaries investigated. In practice, little confusion is likely to result from using either term. Strictly, LSIMS can refer to the use of fast ions (FIB). 

Desorption ionization (DI). General term to encompass the various procedures (e.g., secondary ion mass spectrometry, fast-atom bombardment, californium fission fragment desorption, thermal desorption) in which ions are generated directly from a solid or liquid sample by energy input. Experimental conditions must be clearly stated. 

LSIMS. liquid-phase secondary ion mass spectrometry... 

SIM. selected (or single) ion monitoring SIMS, secondary ion mass spectrometry SIR. selected (or single) ion recording... 

Benninghoven, A., Rudenauer, F.G., and Werner, H.W., Secondary Ion Mass Spectrometry Basic Concepts, Instrumental Aspects, Applications and Trends, Wiley, New York, 1987. 

Vickerman, J.C., Brown, A., and Reed, N.M., Secondary Ion Mass Spectrometry Principles and Applications,... 

Wilson, R.G., Stevie, F.A., and Magee, C.W., Secondary Ion Mass Spectrometry A Practical Handbook for Depth Profiling and Bulk Impurity Analysis, Wiley, Chichester, U.K., 1989. 

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