Sputtered neutral mass spectrometry

Sputtered Neutral Mass Spectrometry (SNMS) is the mass spectrometric analysis of sputtered atoms ejected from a solid surface by energetic ion bombardment. The sputtered atoms are ionized for mass spectrometric analysis by a mechanism separate from the sputtering atomization. As such, SNMS is complementary to Secondary Ion Mass Spectrometry (SIMS), which is the mass spectrometric analysis of sputtered ions, as distinct from sputtered atoms. The forte of SNMS analysis, compared to SIMS, is the accurate measurement of concentration depth profiles through chemically complex thin-film structures, including interfaces, with excellent depth resolution and to trace concentration levels. Genetically both SALI and GDMS are specific examples of SNMS. In this article we concentrate on post ionization only by electron impact. 

In other articles in this section, a method of analysis is described called Secondary Ion Mass Spectrometry (SIMS), in which material is sputtered from a surface using an ion beam and the minor components that are ejected as positive or negative ions are analyzed by a mass spectrometer. Over the past few years, methods that post-ion-ize the major neutral components ejected from surfaces under ion-beam or laser bombardment have been introduced because of the improved quantitative aspects obtainable by analyzing the major ejected channel. These techniques include SALI, Sputter-Initiated Resonance Ionization Spectroscopy (SIRIS), and Sputtered Neutral Mass Spectrometry (SNMS) or electron-gas post-ionization. Post-ionization techniques for surface analysis have received widespread interest because of their increased sensitivity, compared to more traditional surface analysis techniques, such as X-Ray Photoelectron Spectroscopy (XPS) and Auger Electron Spectroscopy (AES), and their more reliable quantitation, compared to SIMS. 

The atom flux sputtered from a solid surface under energetic ion bombardment provides a representative sampling of the solid. Sputtered neutral mass spectrometry has been developed as method to quantitatively measure the composition of this atom flux and thus the composition of the sputtered material. The measurement of ionized sputtered neutrals has been a significant improvement over the use of sputtered ions as a measure of flux composition (the process called SIMS), since sputtered ion yields are seriously affected by matrix composition. Neutral panicles are ionized by a separate process after sputter atomization, and SNMS quantitation is thus independent of the matrix. Also, since the sputtering and ionization processes are separate, an ionization process can be selected that provides relatively uniform yields for essentially all elements. 

Sputtered Neutrals Mass Spectrometry Secondary Neutrals Mass Spectrometry Direct Bombardment Electron Gas SNMS... 

Sputtered Neutral Mass Spectrometry, Glow-Discharge Mass Spectrometry... 

Spurted fibers, 11 240—241 Sputter deposition, 23 7, 24 728-736 advantages and disadvantages of, 24 736 Sputter depth profiling, 24 98-100 Sputtered gold coatings, 12 693 Sputtered neutral mass spectrometry (SNMS), 24 108... 

Another important characteristic is that ion beams can produce a variety of the secondary particles/photons such as secondary ions/atoms, electrons, positrons. X-rays, gamma rays, and so on, which enable us to use ion beams as analytical probes. Ion beam analyses are characterized by the respectively detected secondary species, such as secondary ion mass spectrometry (SIMS), sputtered neutral mass spectrometry (SNMS), electron spectroscopy, particle-induced X-ray emission (PIXE), nuclear reaction analyses (NRA), positron emission tomography (PET), and so on. 

Ion Sources for Secondary Ion Mass Spectrometry (SIMS) and Sputtered Neutral Mass Spectrometry (SNMS)... 

Secondary ion mass spectrometry (SIMS) and sputtered neutral mass spectrometry (SNMS) are today the most important mass spectrometric techniques for surface analysis, especially for thin layer analysis, for depth profiling, for the determination of contaminations and element distribution on a solid sample surface. 

Keywords Silane coupling agent interpenetrating network adhesion sputtered neutral mass spectrometry solubility parameter. 

There are several methods available to probe the actual interphase to demonstrate the existence of interpenetrating networks directly. Among these techniques are depth profiling by SIMS (secondary ion mass spectrometry) or SNMS (sputtered neutral mass spectrometry), and the use of X-ray photoelectron spectroscopy (XPS) depth profiling or Auger electron spectroscopy (AES) depth profiling. 

Figure 2. Depth profile of a polystyrene/Z6020 /Ge laminate obtained using sputtered neutral mass spectrometry. The Z6020 coupling agent was dried at room tempreature (25°C) before application of the polystyrene (from ref. [9]).

SSMS spark source mass spectrometry SSNS sputtered neutrals mass spectrometry PBMS... 

SNMS secondary neutral mass spectrometry sputtered neutral mass spectrometry... 

Jede R, Ganschow O, and Kaiser U (1992) Sputtered neutral mass spectrometry (SNMS). In Briggs D and Seah MP (eds.) Practical Surface Analysis, 2nd edn., vol. 2, pp. 425-506. New York Wiley. 

Kaesdorf S, Hartmann M, Schroder H, and Kompa KL (1992) Influence of laser parameters on the detection efficiency of sputtered neutrals mass spectrometry based on non-resonant multiphoton ionization. International Journal of Mass Spectrometry and Ion Processes 116 219-247. 

Sputtered neutral mass spectrometry (SNMS) depth profiles document that carbon is present in the skin of all fibers to a depth of about 50 nm (Figure 15), whether a given fiber has a secondary carbon sheath overgrowth or not [11]. X-ray photoelectron spectroscopy (XPS)... 

FIGURE 40.18 Depth profiles by laser secondary neutral mass spectrometry (laser SNMS), secondary ion mass spectrometry (SIMS) with Ar and 02 primary ions, and Auger electron spectroscopy (AES) of implanted boron. Reprinted from Higashi, Y., Quantitative depth profiling by laser-ionization sputtered neutral mass spectrometry (1999) Spectrochimica Acta Part B Atomic Spectroscopy, 54(1), 109-122. Copyright (1999), with permission from Elsevier Science. 

Shichi, H., Osabe, S., Sugaya, M., Ino,T, Kakibayashi, H., Kanehori, K., Mitsui, Y. (2003) A resonance photoionization sputtered neutral mass spectrometry instrument for submicron microarea analysis of ULSI devices. Applied Surface Science, 203-204,228-234. 

Higashi, Y. (1999) Quantitative depth profiling by laser-ionization sputtered neutral mass spectrometry. Spectrochimica Acta Part B Atomic Spectroscopy, 54, 109-122. 

Further improvements resulted from the use of a probe for sonication.325 Jhe higher reactivity seems not to be due to an increased surface area, but rather to morphological and composition changes, as evidenced by electron microscopy and sputtered neutral mass spectrometry.i< When applied to ethyl bromo propionate and trifluoroacetaldehyde, the resulting p-hydroxy esters are obtained in good yields with predominance of the threo isomer.272... 

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