Rutherford backscattering spectrometry (RBS) and related techniques have long been used to determine the elemental depth profiles in films a few nanometres to a few microns thick. However, although obtaining spectra is very easy, solving the inverse problem of extracting the depth profiles from the spectra is not possible analytically except for special cases. It is because these special cases include important classes of samples, and because skilled analysts are adept at extracting useful qualitative information from the data, that ion beam analysis is still an important technique.We have recently solved this inverse problem using the simulated annealing algorithm. We have implemented the solution in the 'IBA DataFurnace' code, which has been developed into a very versatile and general new software tool that analysts can now use to rapidly extract quantitative accurate depth profiles from real samples on an industrial scale. We review the features, applicability and validation of this new code together with other approaches to handling IBA (ion beam analysis) data, with particular attention being given to determining both the absolute accuracy of the depth profiles and statistically accurate error estimates.We include examples of analyses using RBS, non-Rutherford elastic scattering, elastic recoil detection and non-resonant nuclear reactions. High depth resolution and the use of multiple techniques simultaneously are both discussed. There is usually systematic ambiguity in IBA data and Butler's example of ambiguity (1990 Nucl. Instrum. Methods B 45 160-5) is reanalysed. Analyses are shown: of evaporated, sputtered, oxidized, ion implanted, ion beam mixed and annealed materials; of semiconductors, optical and magnetic multilayers, superconductors, tribological films and metals; and of oxides on Si, mixed metal silicides, boron nitride, GaN, SiC, mixed metal oxides, YBCO and polymers. OverviewWe will review our recent software developments in thin film depth profiling with ion beam analysis (IBA, see the 6 Centre de Física Nuclear da Universidade de Lisboa, Avenida Prog. Gama Pinto 2, 1699 Lisboa Codex, Portugal Glossary in section 2 for an explanation of the acronyms) in the context of the work of the community; discussing the scientific implications of these developments. We hope to show that these developments improve the usability of IBA to such an extent as to effectively establish a new depth profiling tool.We start (section 2) with a simplified overview of IBA since we believe that our new software tool (the IBA

ABSTRACT:The first analytical intercomparison of fingerprint residue using equivalent samples of latent fingerprint residue and characterized by a suite of relevant techniques is presented. This work has never been undertaken, presumably due to the perishable nature of fingerprint residue, the lack of fingerprint standards, and the intradonor variability, which impacts sample reproducibility. For the first time, time-of-flight secondary ion mass spectrometry, high-energy secondary ion mass spectrometry, and X-ray photoelectron spectroscopy are used to target endogenous compounds in fingerprints and a method is presented for establishing their relative abundance in fingerprint residue. Comparison of the newer techniques with the more established gas chromatography/mass spectrometry and attenuated total reflection Fourier transform infrared spectroscopic imaging shows good agreement between the methods, with each method detecting repeatable differences between the donors, with the exception of matrix-assisted laser desorption ionization, for which quantitative analysis has not yet been established. We further comment on the sensitivity, selectivity, and practicability of each of the methods for use in future police casework or academic research.

The early stages of C 60 bombardment of octane and octatetraene crystals are modeled using molecular dynamics simulations with incident energies of 5-20 keV. Using the AIREBO potential, which allows for chemical reactions in hydrocarbon molecules, we are able to investigate how the projectile energy is partitioned into changes in potential and kinetic energy as well as how much energy flows into reacted molecules and internal energy. Several animations have been included to illustrate the bombardment process. The results show that the material near the edge of the crater can be ejected with low internal energies and that ejected molecules maintain their internal energies in the plume, in contrast to a collisional cooling mechanism previously proposed. In addition, a single C 60 bombardment was able to create many free and reacted H atoms which may aid in the ionization of molecules upon subsequent bombardment events.