Microlocal analysis

G. Kato and D. Struppa, Fundamentals of Algebraic Microlocal Analysis (1999)... 

Vol. 1495 J. M. Bony, G. Grubb, L. Hdrmander, H. Komatsu, J. SjOstrand, Microlocal Analysis and Applications. Montecatini Terme, 1989. Editors L. Cattabriga, L. Rodino. VII, 349 pages. 1991. 

The application of a laser in mass spectrometers offers the possibility of a direct microlocal analysis with a lateral resolution down to the (tm range. The capability of near-field LA-ICP-MS (NF-LA-ICP-MS)65 created in the author s laboratory provides local information on inhomogeneous element distribution on solid sample surfaces with a spatial resolution in the sub-p,m range. 

A laser-induced ToF mass spectrometer (LIMA-2A) was manufactured by Cambridge Mass Spectrometry Ltd., Cambridge, UK, for micro local analysis and was used to analyze thin sections of biological samples in the transmission mode or bulk material in the reflection mode.150,151 Typical LIMA applications in microelectronics include identification of impurities in dielectrics, microlocal analysis, depth profiling, thick film analysis and investigations on hybrid circuits. 

In SIMSLAB from VG Scientific, both surface analytical techniques - SIMS and SNMS - have been applied (see Figure 5.34). In this mass spectrometer different types of primary ion sources are available. Ar+, Cs+, Ga+ or O) primary ions are accelerated in the secondary ion source on the solid sample surface. Similar to the CAMECA IMS-7f, with this experimental arrangement, besides depth profiling, a microlocal analysis can also be performed. The sputtered secondary ions (for SIMS) or the post-ionized sputtered neutrals (for SNMS) - the post-ionization is carried out by an electron beam in an ionizer box (right-hand schematic in Figure 5.34) - are separated... 

Figure 9.13 Microlocal analysis by LA-ICP-MS on a tested solid oxide fuel cell with local Impurities. The small black spots are the laser craters. (]. S. Becker, Spectrochim. Acta 57B, 1805 (2002). Reproduced by permission of Elsevier.)...

In addition to ICP-MS for the multi-element analysis of aqueous solutions, LA-ICP-MS allows the direct determination of trace elements in biological samples and due to this feature it is a well suited analytical technique for microlocal analysis with spatial resolution. In 1995, Outridge el al.lg reported on the performance of an LA-ICP-MS analysis for studying incremental biological structures as archives of trace element accumulation. The use of LA-ICP-MS for several biological (and environmental) applications is reviewed by Durrant and Ward.19 Selected examples for determination of trace elements and species in biological samples are summarized in Table 9.25. 

Consequently, the contamination danger can be minimized. Furthermore, isotope dilution analysis with LA-ICP-MS can be used as a microlocal analytical technique for multi-element determination in thin layers or nanowires of high purity platinum and palladium nanoclusters on DNA. LA-ICP-MS allows microlocal analysis for studying the elemental distribution in layered systems and bulk material. 

Due to the lack of suitable standard reference material for quantification purposes in phospho-proteomics and metallomics, reliable calibration strategies were developed for the direct microlocal analysis of phosphorus and metals in protein spots and in thin sections of brain tissue using LA-ICP-MS.16,17,116 For quantification of analytical data, the application of a solution based calibration strategy was proposed with LA-ICP-MS6 and the simultaneous determination of P, S, Si, Al, Cu and Zn concentrations in human brain proteins (Alzheimer s disease) or for imaging thin... 

The geological MPI-DING references glasses prepared and characterized by Jochum et al. employing several analytical techniques as described in Chapter 6 are recommended to improve possible quantification procedures for in situ microlocal analysis.4,12... 

Inorganic mass spectrometry requires the development of suitable reference materials, such as matrix matched standard reference materials for trace, surface (including depth profiling and microlocal) analysis and/or the creation of matrix independent calibration procedures. The development of species specific standards will be intensified for speciation studies in the future. 

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