Scanning Electron Microscope SEM

Scanning electron microscopes [12] have now become very popular to observe the microstructures on surfaces. With the appropriate equipment, elements contained in extremely small specimen areas can be analyzed. 

The SEM, with a typical magnification of x 300,000 and a resolution of 3 nm in the high vacuum (HV) mode and 5 nm in the low vacuum (LV) mode, has a much greater depth of field than either the optical microscope or the transmission electron microscope (TEM). 

Alignment coils Electron gun chamber isolalion valve 

CARBON FIBERS AND THEIR COMPOSITES — High tension cable 

Specimen chatnber j Backscattered electron detector Specimen holder 

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Fig. 13. Scanning electron microscope (sem) photographs of Parylene C-coated printed circuit conductor peeled to demonstrate the adhesion of the...

Electron Beam Techniques. One of the most powerful tools in VLSI technology is the scanning electron microscope (sem) (see Microscopy). A sem is typically used in three modes secondary electron detection, back-scattered electron detection, and x-ray fluorescence (xrf). AH three techniques can be used for nondestmctive analysis of a VLSI wafer, where the sample does not have to be destroyed for sample preparation or by analysis, if the sem is equipped to accept large wafer-sized samples and the electron beam is used at low (ca 1 keV) energy to preserve the functional integrity of the circuitry. Samples that do not diffuse the charge produced by the electron beam, such as insulators, require special sample preparation. 

Hardness. The Knoop indentation hardness of vitreous sihca is in the range of 473—593 kg/mm and the diamond pyramidal (Vickers) hardness is in the range of 600—750 kg/mm (1 4). The Vickers hardness for fused quartz decreases with increasing temperature but suddenly decreases at approximately 70°C. In addition, a small positive discontinuity occurs at 570°C, which may result from a memory of quartz stmcture (165). A maximum at 570°C is attributed to the presence of small amounts of quartz microcrystals (166). Scanning electron microscopic (sem) examination of the indentation area indicates that deformation is mainly from material compaction. There is htfle evidence of shear flow (167). 

Fig. 2. A series of progressively closer (scanning electron microscope) SEM photographs of the same membrane cross section, clearly showing skin and...

For the purpose of a detailed materials characterization, the optical microscope has been supplanted by two more potent instruments the Transmission Electron Microscope (TEM) and the Scanning Electron Microscope (SEM). Because of its reasonable cost and the wide range of information that it provides in a timely manner, the SEM often replaces the optical microscope as the preferred starting tool for materials studies. 

A CL system attached to a scanning electron microscope (SEM) provides a powerful means for the uniformity studies of luminescent materials with the spatial resolution of less than 1 pm. 

The electron-optical performance of the EPMA system is indistinguishable from that of a conventional scanning electron microscope (SEM) thus, EPMA combines all of the imaging capabilities of a SEM with quantitative elemental analysis using both energy- and wavelength-dispersive X-ray spectrometry. ... 

If an incident electron beam of sufficient energy for AES is rastered over a surface in a manner similar to that in a scanning electron microscope (SEM), and if the analyzer is set to accept electrons of Auger energies characteristic of a particular element, then an elemental map or image is again obtained, similar to XPS for the Quantum 2000 (Sect. 2.1.2.5). 

In electron-optical instruments, e.g. the scanning electron microscope (SEM), the electron-probe microanalyzer (EPMA), and the transmission electron microscope there is always a wealth of signals, caused by the interaction between the primary electrons and the target, which can be used for materials characterization via imaging, diffraction, and chemical analysis. The different interaction processes for an electron-transparent crystalline specimen inside a TEM are sketched in Eig. 2.31. 

Fig. 5. Scanning electron microscope (SEM) images of aligned MWCNT of uniform length (40 pm) and diameters (30-50 nm). Scales bars are 10 pm (top) and 1 pm (bottom) (Courtesy of Drs. M. Terrones and D. R. M. Walton).

Fig. 4. Scanning electron microscope (SEM) image of FeCl3-intercalated CNTs assuming a bead-string structure with partially intercalated and swelled portions.

FIGURE 3.4 Scanning electron microscopic (SEM) images of acrylic copolymer-silica hybrid nanocomposites synthesized from (a) 10 wt% and (b) 50 wt% tetraethoxysilane (TEOS) concentrations. The first number in the legend indicates the wt% of ethyl acrylate (EA) (85) in the ethyl acrylate-butyl acrylate (EA-BA) copolymer, N stands for nanocomposite, and the last number (10, 50) is indicative of the tetraethoxysilane (TEOS) concentration. (From Patel, S., Bandyopadhyay, A., Vijayabaskar, V., and Bhowmick, A.K., J. Mater. Sci., 41, 926, 2006. Courtesy of Springer.)... 

FIGURE 3.8 Scanning electron microscopic (SEM) pictures of acrylic mbber (ACM)-silica hybrid composites (a) synthesized from 50 wt% tetraethoxysilane (TEOS) and (b) synthesized from 10 parts of precipitated silica. (From Bandyopadhyay, A., Bhowmick, A.K., and De Sarkar, M., J. Appl Polym. Sci., 93, 2579, 2004. Courtesy of Wiley InterScience.)... 

FIGURE 3.12 Morphology of mbber-silica hybrid composites synthesized from solution process using different solvents (a) and (b) are the scanning electron microscopic (SEM) pictures of acrylic rubber (ACM)-silica hybrid composites prepared from THF (T) and ethyl acetate (EAc) (E) and (c) and (d) are the transmission electron microscopic (TEM) pictures of epoxidized natural rubber (ENR)-siUca hybrid composites synthesized from THF and chloroform (CH). (From Bandyopadhyay, A., De Sarkar, M., and Bhowmick, A.K., J. Appl. Polym. Sci., 95, 1418, 2005 and Bandyopadhyay, A., De Sarkar, M., and Bhowmick, A.K., J. Mater. Sci., 40, 53, 2005. Courtesy of Wiley InterScience and Springer, respectively.)... 

FIGURE 3.16 Morphology and visual appearance of acrylic rubber (ACM)-silica and epoxidized natural rubber (ENR)-silica hybrid composites prepared from different pH ranges (a) transmission electron microscopic (TEM) picture of ACM-siUca in pH 1.0-2.0, (b) scanning electron microscopic (SEM) picture of ACM-siUca in pH 5.0-6.0, (c) SEM image of ACM-siUca in pH 9.0-10.0, (d) TEM picture of ENR-silica in pH... 

First of all, only the samples, prepared according to the procedure (a) were suitable for scanning electron microscope (SEM) measurements. All other samples were very un-... 

Fulda and Tieke [77] studied the effect of a bidisperse-size distribution of latex particles on the structure of the resulting LB monolayer. For this purpose, a mixed colloidal solution of particles la and lb was spread at the air-water interface. Particles la had a diameter of 434 nm, particles lb of 214 nm. The monolayer was compressed, transferred onto a solid substrate, and viewed in a scanning electron microscope (SEM). In Figure 10, SEM pictures of LB layers obtained from various bidisperse mixtures are shown. 

Permeation measurements were conducted on the Pd and Pd-Ag/PSS membranes at elevated temperature (623 K to 873 K) and pressures (up to 1 MPa). Surfece morphology of the deposited layer was observed with a scanning electron microscope (SEM, S3(K)0N, HITACHI Co.) equipped with an energy dispersive spectrometer (EDS, HORIBA Co.). 

There are three types of electron microscopes commonly used for microanalysis. These are the scanning electron microscope (SEM) with X-ray detectors, the electron probe microanalyser (EPMA), which is essentially a purpose built analytical microscope of the SEM type, and transmission microscopes (TEM and STEM) fitted with X-ray detectors. In a TEM, compositional information may also be obtained by... 

Nitrogen adsorption isotherms were measured with a sorbtometer Micromeretics Asap 2010 after water desorption at 130°C. The distribution of pore radius was obtained from the adsorption isotherms by the density functional theory. Electron microscopy study was carried out with a scanning electron microscope (SEM) HitachiS800, to image the texture of the fibers and with a transmission electron microscope (TEM) JEOL 2010 to detect and measure metal particle size. The distribution of particles inside the carbon fibers was determined from TEM views taken through ultramicrotome sections across the carbon fiber. 

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