Dynamic Secondary Ion Mass Spectrometry SIMS

Material properties often depend on the constituents of inclusions as small as a few micrometers large or surface layers with a thickness of 0.1-100 nm. From the 1970s onward, microanalysis has become a major challenge. Initial methods such as electron probe X-ray microanalysis (EPXMA) or dynamic secondary ion mass spectrometry (SIMS) determine elements at the microscopic scale, but charge buildup and beam-induced sample damage hamper their application to nonconducting organic materials. 

Guerquin-Kern, J. L., Wu, T. D., Quintana, C., Croisy, A. (2005) Progress in analytical imaging of the cell by dynamic secondary ion mass spectrometry (SIMS microscopy). Biochim Eiophys Acta, 1724, 228-238. 

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]. 

Spectrometric Analysis. Remarkable developments ia mass spectrometry (ms) and nuclear magnetic resonance methods (nmr), eg, secondary ion mass spectrometry (sims), plasma desorption (pd), thermospray (tsp), two or three dimensional nmr, high resolution nmr of soHds, give useful stmcture analysis information (131). Because nmr analysis of or N-labeled amino acids enables determiaation of amino acids without isolation from organic samples, and without destroyiag the sample, amino acid metaboHsm can be dynamically analy2ed (132). Proteia metaboHsm and biosynthesis of many important metaboUtes have been studied by this method. Preparative methods for labeled compounds have been reviewed (133). 

Dynamic Secondary Ion Mass Spectrometry (Dynamic SIMS)... 

Secondary Ion Mass Spectrometry Dynamic Secondary Ion Mass Spectrometry Static Secondary Ion Mass Spectrometry SIMS using a Quadruple Mass Spectrometer SIMS usii a Magnetic Sector Mass Spectrometer See Magnetic SIMS... 

In secondary ion mass spectrometry (SIMS) the sample surface is sputtered by an ion beam and the emitted secondary ions are analyzed by a mass spectrometer (review Ref. [360]). Due to the sputtering process, SIMS is a destructive method. Depending on the sputtering rate we discriminate static and dynamic SIMS. In static SIMS the primary ion dosis is kept below 1012 ions/cm2 to ensure that, on average, every ion hits a fresh surface that has not yet been damaged by the impact of another ion. In dynamic SIMS, multiple layers of molecules are removed at typical sputter rates 0.5 to 5 nm/s. This implies a fast removal of the topmost layers of material but allows quantitative analysis of the elemental composition. 

Figure 8 Atomika Dynamic In Depth Analyzer (ADIDA), quadrupole-based-imaging secondary ion mass spectrometry (SIMS) instrument.

Secondary ion mass spectrometry (SIMS) is to measure the secondary ions, ionized clusters, atoms and atomic clusters, which are emitted from the surface of particles, when it is bombarded with a primary beam of ions, such as He", Ne", or Ar", with energies in the range of hundreds of eV to keV scale. The emitted ions and ionized clusters are analyzed directly by using a mass spectrometer. Therefore, chemical composition of the surface can be analyzed with the obtained accordingly. SIMS has two modes of analysis (i) static and (ii) dynamic. Static SIMS uses an ion beam with low current density, so as to confine the analysis to the outermost layers. Dynamic SIMS uses beams of high current density, so that successive atomic layers can be eroded at a relatively high rate. Comparatively, the analytical conditions of dynamic SIMS are less suitable for surface analysis. 

Secondary-ion mass spectrometry (SIMS) is used largely as a surface characterization technique [18]. It is practiced in two formats, dynamic SIMS and static SIMS. In both formats, a beam of keV-energy ions, usually of Ar ions, bombards the surface of the sample directly. The momentum transfer from the beam to the... 

The ultrahigh vacuum technique of secondary ion mass spectrometry (SIMS) is the most sensitive of all the commonly employed sruface analytical techniques. There are a number of variants of the technique for example, static SIMS is used to examine submonolayer elemental analysis, dynamic SIMS is used to obtain compositional information as a function of depth below the sruface, and imagining SIMS is used for spatially resolved elemental analysis. Specimens commonly examined by SIMS are 2.5 cm in diameter and 1 cm thick. When ceramic materials are examined, sample charging is prevented by flooding the surface of the sample with an electron beam. Dynamic SIMS is of great interest and has been used to study changes in elemental composition from weathered or corroded surfaces of samples into the bulk matrix. 

Three different experiments for surface and interface analysis are possible by SIMS (secondary ion mass spectrometry) SIMS static, dynamic and imaging SIMS. 

The chemical mapping of simple ions such as C, Na, and have been applied to the TOF-SIMS analysis of biological samples of organs, tissues, and cells [22-27,89,90], and 3D images of the elemental distributions [91] have also been obtained. In addition, lateral and 3D distributions of Na+, K+, Ca+, and isotope-labeled elements in cells can be obtained with dynamic secondary ion mass spectrometry (DSIMS) imaging techniques [91,92]. 

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