Glass SIMS depth profiles

Figure 1. SIMS depth profiles in a simulated nuclear waste glass. Major and minor elemental profiles are shown for fractured surfaces exposed to 25° C aqueous leaching for 2 d (a) and 50 d (b). (Reproduced, with permission, from Ref. 4. Copyright 1980, North-Holland Publishing Co.)...

Figure 2. SIMS depth profiles for a sodium borosilicate glass blank sample, air-exposed only (a), and sample exposed to aqueous leaching at 25°C for 30 min (b).

Figure 3. Comparison of SIMS depth profiles of aqueous leaching of a sodium borosilicate glass, for 30 min (a). Key ----------, 0°C and--------, 25°C. Error func-...

Figure 4. SIMS depth profiles for a borosilicate glass exposed to 0°C aqueous leaching for periods of 5 (-----------------------) and 30 (------) min.

Fig. 4.52. SIMS and IBSCA depth profiles of the altered layer region of a lithium aluminosilicate (LAS) glass ceramic (conditions SkeVAr" ).

Secondary ion mass spectrometry (SIMS) is a widespread analytical technique for the study of surfaces in materials science. Mostly used for elemental analyses and depth profiling, it is particularly relevant for many different fields of research including cultural heritage studies. Reviews of its use for the study of ancient glasses or metal artefacts already exist in the literature [Spoto 2000, Darque-Ceretti and Aucouturier 2004, Dowsett and Adriaens 2004, Adriens and Dowsett 2006, Anderle et al. 2006, McPhail 2006], but as only elemental information is obtained, these studies are limited to inorganic materials. 

Dynamic SIMS is used for depth profile analysis of mainly inorganic samples. The objective is to measure the distribution of a certain compound as a function of depth. At best the resolution in this direction is < 1 nm, that is, considerably better than the lateral resolution. Depth profiling of semiconductors is used, for example, to monitor trace level elements or to measure the sharpness of the interface between two layers of different composition. For glass it is of interest to investigate slow processes such as corrosion, and small particle analyses include environmental samples contaminated by radioisotopes and isotope characterization in extraterrestrial dust. 

FIG. 3. Depth profiles of components on glass electrodes as measured by the SIMS technique. 

Depth profiling glasses with ion beam techniques is also difficult due to surface charging problems. Pulsed ion beams in ToF-SIMS with relatively long interpulse periods have been used successfully, however. ARXPS can be used to study variation in composition and chemical states over the outer 10 nm. Nuclear techniques, such as PIXE, NRA, RBS and ERDA, are particularly useful in studying the composition of deeper lying altered layers to depths of pm. The latter techniques generally have depth resolutions of the order of 10 nm which is sufficient in most cases [93]. 

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