Germanium depth profile

Fig. 2 shows one application of ATR depth profiling. In this case, ATR spectra were obtained as a function of angle of incidence from a polymethylmethacrylate (PMMA) film of thickness 0.5 p.m that was deposited onto a germanium hemi-cylinder [4]. The solid line represents the ATR spectrum of PMMA while the squares represent the film thickness that was recovered from the infrared spectra using four different bands. It can be observed that the recovered film thickness was very close to the measured thickness. 

FIGURE 2. Depth profile of germanium compounds in Baltic Sea (modified from Reference 11) MeGe, monomethylgermanium Me2Ge, dimethylgermanium Asi, total dissolved inorganic arsenic... 

The measurements of F depth profiles in chipped flints have been realised using the 4.7 keV wide 872 keV 19F(p,a12.3y)160 resonance. This reaction provides a good depth resolution (about 100 nm in Si02). The 4-7.5 MeV y-rays are detected with a BGO (bismuth germanium oxide) detector at 0°C with respect to the incident beam. The flint artefacts can be settled in the vacuum chamber as whole pieces without any sample preparation [35],... 

Figure 8 shows an example of the depth-profile study using the ATR technique. The sample was vapor deposited poly-para-xylylene on polyethylene. The Figure shows the ATR spectra of the sample recorded using a germanium (45°) crystal and a KRS-5 (60O) crystal. These last... 

The biological pump influences, to varying degrees, the distribution of many elements in seawater besides carbon, nitrogen, phosphorus, and silicon. Barium, cadmium, germanium, zinc, nickel, iron, selenium, yttrium, and many of the REEs show depth distributions that very closely resemble profiles of the major nutrients. Additionally, beryllium, scandium, titanium, copper, zirconium, and radium have profiles where concentrations increase with depth, although the correspondence of these profiles with nutrient profiles is not as tight (Nozaki, 1997). 

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