Gradient sputtering

Figure 3.5 Details of sputtering plant for gradient sputtering (a single aperture orifice is shown in the lower right photograph) (source IMM).

Steam to carbon ratio Sensor analytical manager Split-and-recombine Sodium dodecyl sulphate Scanning electron microscopy Simultaneous gradient-sputtering Staggered herringbone mixer Static mixing elements... 

Ion sputtering mass spectrometry has been applied to several problems in the analysis of solids with various types of instruments. These include studies of semiconductor devices as shown in Fig. 3. oxygen concentrations and concentration gradients and of processes of oxidation in a variety of metals, some catalytic and corrosion processes on metals, and the chemistry of trace elements in geologic specimens. The distribution of trace elements in lunar rocks has also been studied. 

The catalysts to be deposited are inserted into the sputter plant as the so-called targets. The shuttle carries the titer-plate and revolves below the metal targets (Figure 3.4). In every rotation up to three sublayers are deposited. For a binary system, the sublayer thickness was 10 nm in each revolution. The thickness gradients were realized by aperture orifices which shaped the particle beam (Figure 3.5). 

In certain applications of plasma polymerization, the incorporation of electrode material, particularly in a controlled and designed manner, is extremely useful and becomes a great asset in LCVD. For instance, a thin layer of plasma polymer of methane with a tailored gradient of copper has been shown to improve the adhesion of the thin layer to a copper substrate as well as the adhesion of metal to a polymer film [3,4]. In general applications of LCVD, in which the metal contamination should be avoided, it is important to select the electrode material that has low sputtering yield. Titanium has been used successfully in such cases. 

Fig. 8.10. Sputter atomization and ionization processes occurring in a glow-discharge. M cathode metal atom, f potential gradient of cathode fall. (Reproduced with permission of the American Chemical Society.)...

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