Sputtering time

If the primary ion beam is used to continuously remove material from the surface of a specimen in a given area, the analytical zone is advanced into the sample as a function of the sputtering time. By monitoring the secondary ion count rates of selected... 

Figure 3a Unprocessed depth profile (secondary ion intensity versus sputtering time) of a silicon sample containing a boron ion implant.

Figure 3b Depth profile in (a), after converting the sputtering time to depth and the sec-...

A mass scan is acquired in cases when a survey of all impurities present in a volume of material is needed. Rather than measuring the secondary ion count rates of preselected elements as a fimction of sputtering time the count rates of all secondary ions are measured as a fimction of mass. Because a mass scan is continuously acquired over a mass range, no depth profiling or lateral information is available while operating in this mode. Figure 4 shows a mass scan acquired from a zirconia... 

By acquiring mass-resolved images as a function of sputtering time, an imaging depth profile is obtained. This combined mode of operation provides simultaneous lateral and depth resolution to provide what is known as three-dimensional analysis. 

Fig. 3.38. HF-plasma SNMS sputter time profile (HFM) ofa multilayer system consisting of five double layers, 100 nm Si02 + 100 nm Si3N4, each, on a glass substrate (courtesy V.-D. Hodo-roaba, BAM Berlin, and Schott Glas, Mainz, Germany).

XPS can be used to determine the composition of a solid as a function of distance away from the surface and into the bulk of the solid. Such a depth profile can be constructed in two ways. One way in which a depth profile can be constructed is by using a beam of inert gas ions to sputter away material from the surface of the sample and to then record the XPS spectrum. If this procedure is repeated several times, a profile showing the composition of the material as a function of sputtering time and thus of depth into the sample can be constructed. Another way to construct a depth profile involves tilting the sample with respect to the X-ray beam. In Fig. 17A, the take-off angle or the angle between the sample surface and the direction of propagation of the ejected photoelectrons is 90 . In... 

The Fe-N /Ti-N nano-multilayers were prepared by using the magnetron-sputtering technique [34]. Si (111) wafers are used as the substrate. The multilayers have a total thickness of about 500 nm with alternately Fe-N and Ti-N layers (shown in Fig. 38). The Fe-N layer was the outermost layer and the Ti-N layer was the iimermost layer. The thickness of each layer was strictly controlled by the sputtering time. Table 4 shows the thickness of each layer of the samples. Because the multilayer sample was supposed to be used as the magnetic write head, the thickness of the nonferromagnetic Ti-N layer was not changed. 

Figure 5. Morphology and particle size distribution of an island silver thin film deposited on native oxide covered silicon (a) before ion bombardment and after (b) 0.5 keV Ar sputtering with 1.1 X 10, (c) 2.5 X 10, and (d) 3.9 x 10 ion/cm dose. Sputtering speed for silver was around 3-4ML/min. Total elapsed sputtering time is indicated on each size distribution graphs. (Reprinted from Ref [123], 2003, with permission from Springer.)...

Figure 11. Size dependence of the UPS valence band spectra from gold nanoparticles. The sputtering time on curves (a), (b), and (c) are the same as in Figure 9. Curves (bi) and (b2) were recorded after 20 and 25min. (Reprinted from Ref [171], 2002, with permission from Elsevier.)...

The SNMS depth profile (ion intensity as a function of sputter time) for the matrix elements of a Ba07Sr03TiO3 layer on a silicon substrate with Pt/Ti02/Si02 buffer layers is illustrated in Figure 9.8. Inhomogeneity of the perovskite layer was detected especially for Sr. Furthermore, an interdiffusion of matrix elements of the Ba07Sr03TiO3 layer and of the Pt barrier layer was observed. 

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