Abstract: Laser microprobe mass spectrometry (LMMS) aims at the identification of local organic and inorganic constituents at the surface of solids, The low mass resolution capabilities of the initially used time-of-flight (TOF) mass spectrometers have often proved to be insufficient for identification, Therefore, high mass resolution Fourier transform (ET) LMMS was developed, Neo-ceramic powders with oxide or carbide coatings were analyzed by both FT LMMS and TOF LMMS, The data are useful to compare the analytical information gained from both methods, Analytical results of these samples by electron microprobe x-ray analysis (EPXMA) and secondary ion mass spectrometry (SIMS) are discussed to assess the place of FT LMMS and TOF LMMS in the spectrum of microanalytical techniques.

Abstract: The quartic force field of thioformaldehyde has been calculated ab initio using large basis sets and augmented coupled cluster methods. Calculated fundamentals are in excellent agreement with experiment, as is the most important Coriolis coupling constant. Computed values for the anharmonicity, rovibrational coupling, and centrifugal distortion constants of the four isotopomers (H2CS)-S-32, (H2CS)-S-34, (HDCS)-S-32, and (D2CS)-S-32 have been reported. Predictions have been made for all vibrational transitions from the ground state to excited states with at most two quanta for these isotopomers, both using second-order perturbation theory corrected for Darling-Dennison resonance and using vibrational SCF-CI calculations. For (D2CS)-S-32, perturbation theory performs quite well; for the other isotopomers, performance is poorer for states involving excitation of the out-of-plane bend and, for the (H2CS)-S-32 and (H2CS)-S-34 isotopomers, also for the antisymmetric bend that is in severe Coriolis resonance with it. A possible explanation has been suggested. (C) 1994 Academic Press, Inc.

Abstract: The technique of imaging time-of-flight secondary ion mass spectrometry (TOF-SIMS) and dual beam depth,profiling has been used to study the composition of the surface of tabular silver halide microcrystals. Analysis of individual microcrystals with a size well below 1 mum from a given emulsion is possible. The method is successfully applied for the characterization of silver halide microcrystals with subpercent global iodide concentrations confined in surface layers with a thickness below 5 nm. The developed TOF-SIMS analytical procedure is explicitly demonstrated for the molecular imaging of adsorbed thiocyanate layers (SCN) at crystal surfaces of individual crystals and for the differentiation of iodide conversion layers synthesized with KI and with AgI micrates (nanocrystals with a size between 10 and 50 nm). It can be concluded that TOF-SIMS as a microanalytical, surface-sensitive technique has some unique properties over other analytical techniques for the study of complex structured surface layers of silver halide microcrystals. This offers valuable information to support the synthesis of future photographic emulsions.

Abstract: Based on the existing experimental data and their statistical errors, it is not possible to make a sound recommendation of the cross-section set of Campbell et al (J. Phys. B: At. Mol. Opt. Phys. 34 (2001) 1185). We comment on this paper.

Abstract: Fourier transform laser microprobe mass spectrometry (FT LMMS) has been developed for the molecular analysis of both organic and inorganic components at the surface of microobjects with the ultimate specificity of high-mass resolution. These capabilities are needed in numerous applications of practical material analysis, such as tracing back anomalies in microobjects. The purpose of this paper is to address representative example from industrial trouble shooting, in which organic and inorganic analytes in a single microparticle have been identified unambiguously. This motivates the research to extend the methodology towards quantification. This paper deals with the fundamental aspect of information depth, specifically for inorganic molecular adduct ions. Finally, data will show the quantitative capabilities of FT LMMS. A suitable methodology for the preparation of reference specimens has allowed the empirical calibration of the response as a function of the local concentration to be achieved.

Abstract: We analyzed ultra-thin ZrO2/SiO2/Si gate dielectrics under post-deposition anneals in dry O-2 at temperatures from 500 to 700 degreesC. TOF-SIMS profiling of ZrO2/SiO2/Si stacks is hampered by many sputter induced artifacts. The depletion of oxygen leads to a decrease in SIMS intensities. However, preferential sputtering is accompanied by transport of the depleted species towards the surface. Due to recoil implantation oxygen gets piled-up near the ZrO2/SiO2 interface. Either normal or radiation-enhanced diffusion transports oxygen back to the surface. Simultaneously also segregation of zirconium towards and through the interface is observed, resulting in a large zirconium tail in the underlying silicon substrate. (C) 2002 Elsevier Science B.V. All rights reserved.