Secondary Ion mass spectrometer

Fig. 45—The schematic of a Time-of-Flight Secondary Ion Mass Spectrometer.

Secondary Ion Mass Spectrometers (SIMS) and Sputtered Neutral Mass Spectrometers (SNMS)... 

A few SIMS and SNMS instruments for surface analysis187-189 are commercially available on the analytical market. These are SIMS instruments using a double-focusing sector field mass spectrometer (e.g., CAMECA IMS-7f), time-of-flight secondary ion mass spectrometers (ToF-SIMS IV from CAMECA, Cedex, France, or ToF-SIMS 5, the ToF-SIMS 300 from ION-TOF, Munster, Germany and the PHI TRIFT IV from Physical Electronics, USA) and quadrupole based SIMS (SIMS 4550 and 4600 CAMECA, Cedex, France) or the quadrupole based SNMS instruments with SIMS option (INA-X, SPECS GmbH, Berlin, Germany). 

Figure 5.31 Instrumental arrangement of secondary ion mass spectrometer, CAMECA IMS 7f (Reproduced by permission of CAMECA, www.cameca.com.)...

In spite of the high cost of secondary ion mass spectrometers and the technical expertise required, this sensitive microlocal and surface analytical technique can be applied successfully in forensic studies, e.g., for measurement of trace elements and inks on counterfeit banknotes.18... 

Secondary Ion Mass Spectrometer Design Considerations for Organic and Inorganic Analysis... 

Figure 1. Schematic representation of a secondary ion mass spectrometer.

Figure 5 Ion microprobe mass analyzer, first scanning-probe imaging secondary ion mass spectrometer (SIMS). (From Ref. 24.)...

Figure 28 Example of positive and negative secondary ion mass spectrometer (SIMS) mass spectra. An 160" primary beam of 1 nA at 15 keV was used for these spectra of 347 and 304 stainless steels, (a) Positive ion spectrum 347 stainless steel and (b) negative ion spectrum 304 stainless steel. (From Ref. 84.)... 

At its simplest the secondary ion mass spectrometer needs only five elements. These are an ion source to create the bombarding primary ions, a target or sample holder, a mass analyzer for analysis of the secondary ions, a detector to transform the ions to recordable form, and a recording device. Usually, the practical SIMS... 

A secondary ion mass spectrometer (SIMS) able to analyze the chemical composition and speciation of the surface of ion emitters at full operating temperature... 

The principles of ion sources which use a primary ion beam for sputtering of solid material on sample surface in a high vacuum ion source of a secondary ion mass spectrometer or a sputtered neutral mass spectrometer are shown in Figure 2.30a and Figure 2.30b, respectively. Whereas in SIMS the positive or negative secondary ions formed after primary ion bombardment are analyzed, in SNMS the secondary sputtered ions are suppressed by a repeUer voltage and the sputtered neutrals which are post-ionized either in an argon plasma ( plasma SNMS ), by electron impact ionization ( e-beam SNMS ) or laser post-ionization are nsed for the surface analysis (for details of the ionization mechanisms see references 122-124). 

J., Jeffery, M., Rowland, B. (2002). Hydrolysis of VX on concrete rate of degradation by direct surface interrogation using an ion trap secondary ion mass spectrometer. Environ. Sci. Technol. 36 4790. ... 

Kita N. T., Liu Y. Z., Ikeda Y., Prinz M., and Morishita Y. (2000) Identification of a variety of clasts in the Dar al Gani 319 polymict ureihte using secondary ion mass spectrometer oxygen-isotopic analyses. Meteorit. Planet. Sci. 35, A88-A89. 

Figure 16.18. Schematic diagram of a secondary-ion mass spectrometer. This particular design is called the Ion Microprobe because very small areas can be investigated with it. From Chemical and Engineering News, August 19, 1968, p 30, by permission of the American Chemical Society, copyright owner.

FIGURE 17.17. The Cameca IMS-6F secondary ion mass spectrometer. Figure from De Laeter (2001), pg. 49. 

Figure 2.12 illustrates the mass spectrum of a narrow-dispersed polystyrene sample recorded using a Secondary Ion Mass Spectrometer equipped with a time-of-flight detector (TOF-SIMS). There are a series of mass spectral peaks due to ions of the type H-(St) -C4H9, Ag (silver was added as a cationization agent). Equahon (2.1) yielded Mn = 4550, which is within 8% with the value Mn = 4964 obtained by VPO. 

PHI 550 ESCA/SAM electron spectrometer was used to conduct all the ESCA and AES experiments. Mg Ka x-ray source (400 W) was used for ESCA. PHI 2500 Secondary Ion Mass Spectrometer was used for SIMS experiment. The ESCA exper imental deviation of the measurmeent of binding energy is + 0.1 eV. 

Transportation of Li in the electrolyte through the SEI may occur via several different mechanisms. One possible mechanism is that Li after desolvation directly passes through pores since SEI is porous the other possibility is that Li after desolvation exchanges with Li in the SEI. Recently, Harris et al. provided a more detailed description of ion transport mechanisms in SEI film by using isotope-labeled electrolyte approach [71]. They immersed three copper electrodes which were preformed SEI in LiC104 EC/DEC electrolyte into 1 M LiBp4 EC/DEC electrolyte for 30 s, 3 min, and 15 min. After immersion, the electrodes were rinsed with DMC solvent and then transferred under Ar to a time-of-flight secondary ion mass spectrometer (TOF-MS) the results are shown in Fig. 5.24. 

Niehuis, E., Heller, T., Feld, H., and Benninghoven, A. (1987) Design and performance of a reflectron based time-of-flight secondary ion mass spectrometer with electrodynamic primary ion mass separation. J. Vac. Sci. TechnoL, A5,1243-1246. 

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