NanoSIMS

The Mattauch-Herzoggeometry (Fig. 3.20) enables detection of several masses simultaneously and is, therefore, ideal for scanning instruments [3.49]. Up to five detectors are adjusted mechanically to locations in the detection plane, and thus to masses of interest. Because of this it is possible to detect, e. g., all isotopes of one element simultaneously in a certain mass range. Also fast, sensitive, and precise measurements of the distributions of different isotopes are feasible. This enables calculation of isotope ratios of small particles visible in the image. The only commercial instrument of this type (Cameca Nanosims 50) uses an ion gun of coaxial optical design, and secondary ion extraction the lateral resolution is 50 nm. 

B. Marino, J. J. Boon, E. Hendricks, F. Horreard and F. Hillion, Imaging ToF SIMS and NANOSIMS studies of barite celestite particles in grounds from paintings by Van Gogh, e Preservation... 

Besmehn A, Hoppe P (2003) A NanoSIMS study of Si- and Ca-Ti-isoptopic compositions of presolar silicon carbide grains from supemovae. Geochim Cosmochim Acta 67 4693-4703... 

Meyer BS (1994) The r-, s-,and p-processes in nucleosynthesis. Annu Rev Astronom Astrophys 32 153-190 Mostefaoui S, Lugmair GW, Hoppe P, El Goresy A (2003) Evidence for live iron-60 in Semarkona and Chervony Kut a nanosims study. Lunar Planet Sci XXXIV 1585 Murthy VR, Sandoval P (1965) Chromium isotopes in meteorites. J Geophys Res 70 4379-4382 Nicolussi GK, Davis AM, Pellin MJ, Lewis RS, Clayton RN, Amari S (1997) s-Process zirconium in presolar silicon carbide grains. Science 277 1281-1283... 

As with the electron microprobe, the chemical composition is determined through comparison with standards. Corrections for interactions with different elements are also necessary. However, the standardization and correction procedures for the AES are much less mature than those for the electron probe. In cosmochemistry, the auger nanoprobe is used primarily to determine the chemical compositions of presolar grains. It is ideal for this application because it is a surface technique and has the same spatial resolution as the NanoSIMS (see below), which is used to identify presolar grains in situ in meteorite samples and IDPs. 

The Cameca ims 1280 is an ion microscope as well as an ion microprobe. That means that it can transmit direct ion images to an image detector. This capability has now been adapted for semi-quantitative and quantitative ion imaging. Direct ion imaging does not depend on the size of the primary ion beam for its spatial resolution. The new solid-state SCAPS detector has a spatial resolution of less than a micron, close to that of the NanoSIMS (see below). 

Figure 5.35 Instrumental setup of multiple ion collector NanoSIMS 50 ion microprobe. (Reproduced by permission of CAMECA, www.cameca.com.)...

Instruments CAMECA IMS 7f (CAMECA), ToF-SIMS (ION-TOF), Quad-SIMS 4550 (CAMECA), NanoSIMS 50 (CAMECA) SIMSLAB (VG Scientific), INA X (Specs GmbH)... 

The surface behaviour of a two-phase polymer mixture depends on the chemical structure of the polymer components, the interaction between the two polymers and the processing conditions, which was studied by ToF-SIMS to obtain the molecular surface composition. NanoSIMS as a... 

Hillion et al. [61] reported the development of the Cameca NanoSIMS 50, a commercial instrument for the analysis of submicrometer features. This instru-... 

Figure 14 Ion optical system of the NanoSIMS 50 high-spatial-resolution, high-mass-resolution scanning-probe instrument. (From Ref. 61.)...

Behrens, S., Losekann, T., Pett-Padge, J., Weber, P. K., Ng, W. O., Stevenson, B. S., et al. (2008). Linking microbial phylogeny to metabolic activity at the single-cell level by using enhanced element labeHng-catalyzed reporter deposition fluorescence in situ hybridization (EL-FISH) and NanoSIMS. Appl. Environ. Microbiol. 74, 3143—3150. 

Another interesting suite of approaches that undoubtedly wiU be further developed employs SIMS—secondary isotope mass spectrometry (also know as multiple-isotope imaging mass spectrometry (MIMS)). Orphan et al. (2001) applied FISH—SIMS or fluorescent in situ hybridization SIMS to detect isotopicaUy Ught carbon in archaeal ceUs, identifying the Archaea by FISH and using SIMS to quantify the isotopic composition of individual ceUs by ion microprobe. Finzi et al. (2006) applied nanoSIMS to visualize uptake of N2 and C02 by individual ceUs of a... 

Continuing instrumental developments allow us to make new and more measurements on the grains and likely lead to new discoveries. For example, the NanoSIMS features high spatial resolution and sensitivity, making isotopic analysis of small grains possible, and this capability has already resulted in the discovery of presolar silicate grains in IDPs (Messenger et al., 2003)... 

Mostefaoui S., Eugmair G. W., Hoppe P., and El Goresy A. (2003) Evidence for live iron-60 in Semarkona and Chervony Kut a NanoSIMS study. In Lunar Planet. Sci. XXXIV, 1585. The Eunar and Planetary Institute, Houston (CD-ROM). 

A new type of ion microprobe, the NanoSIMS, has made it possible to measure the isotopic compositions of chondritic IDPs on a scale of 0.5-1 pm (Floss and Stadermann, 2003 Messenger et al., 2003). Six silicate grains identified by Messenger et al. in nine chondritic IDPs have isotopic compositions confirming their presolar origins. Three of the grains exhibit elevated ratios and solar ratios... 

Although hints of depletions of (with large errors) have previously been reported (McKeegan, 1987), the NanoSIMS measurements provide the first indication of correlated carbon and nitrogen isotope anomalies. 

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