Probing depth

Zone 2 The area of coverage of the probe begin to interact with the slot. The impedance change increases. This situation is true over the probe depth, that is to say until the inner coil reaches the edge of the slot. The range of the zone is [x 1 x2]... 

A depth profile is a record of the variation of a property (such as composition) as a function of depth. Some of the techniques in this volume have essentially no intrinsic depth profiling capabilities the signal is representative of the material integrated over a fixed probing depth. Most, however, can vary the depth probed by varying the condition of analysis, or by removing the surface, layer by layer, while collecting data. 

Detection limits Depth probed Depth profiling... 

Site symmetry Depth Probed Depth profiling Detection limits Lateral resolution Imaging/mapping... 

Detection limit Quantification Dynamic range Probing depth Lateral resolution Mass range... 

Bulk analysis Depth probed Depth profiling Lateral resolution... 

Destructive Chemical bonding Quantification Accuracy Detection limits Depth probed Depth resolution Lateral resolution Imaging/ mapping... 

One should compare capabilities to the electron beam X-ray emission methods of Chapter 3. The major difference is the higher lateral resolution with electron beams and the associated mapping capabilides. Another difference is the shorter probing depth possible with electrons, except when compared to the specialized TXRF method. Comparing electron-beam EDS to X-ray/particle EDS or electron-beam WDS to X-ray/particle WDS, the electron beams have poorer detection limits because of the greater X-ray bacl ound associated with electron... 

Probing depth Depth resolution Mass resolution Sensitivity... 

RBS is a quantitative analytical tool which provides simultaneously the depth profile and the composition by mass number of the sample. The disadvantage is that a large and expensive particle accelerator is required to produce the incident beam. The probe depth of RBS is typically 1-2 pm with a depth resolution of 20-30 nm. 

When investigating opaque or transparent samples, where the laser light can penetrate the surface and be scattered into deeper regions, Raman light from these deeper zones also contributes to the collected signal and is of particular relevance with non-homogeneous samples, e.g., multilayer systems or blends. The above equation is only valid, if the beam is focused on the sample surface. Different considerations apply to confocal Raman spectroscopy, which is a very useful technique to probe (depth profile) samples below their surface. This nondestructive method is appropriate for studies on thin layers, inclusions and impurities buried within a matrix, and will be discussed below. 

Figure 7. Pressure field map for the same house as shown in Figure 6. The probe depth code is the same as for Figure 6. The numbers show the pressure decrease at each probe measured with respect to atmospheric pressure induced by a pressure difference in the basement of -34 Pa.

Fig. 15.5 Cover penetration depth as a function of the effective refractive index. Using a substrate with RI less than the RI of the aqueous cover solution, the penetration depth into the aqueous cover can be tuned up to infinity. While using glass as a substrate with RI of 1.53 the probing depth has a maximum value around 180 nm, using a light wavelength of 633 nm...

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