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Ribbon beam

This transmission method provides an image of a section through the crystal and as such enables the experimenter to study the three-dimensional distribution of defects. The beam from the spot of a fine-focus or microfocus source is collimated into a ribbon beam of width approximately 10 //m before the singlecrystal specimen. This provides an incident beam of width small compared with that of the base of the Borrmaim fan formed by extremes of the diffracted and transmitted beams with the crystal surface. [In other words, the beam width must... [Pg.185]

Single-Wafer Endstation Linear Mechanical Scan with Unscanned Ribbon Beam... [Pg.229]

Travel Path Length Effect for a Ribbon Beam on a Single-Wafer Endstation... [Pg.234]

After 1942 the diffraction techniques were improved to the point where resolution of consecutive small-angle layer hnes became possible (18, 128). Success was secured by the use of finely collimated beams, large specimen-to-film distances, and long exposure times. Economy of radiation was improved by using slits to form ribbon beams, which because of cross-fire of great aperture orthogonal to the fiber axes of specimens, contributed adequate intensity to meridionally separated points of the registering film (see Fig. 2). [Pg.99]

The detectors were made from pure (Series 1100) aluminum plates with a coated area of 3 X 20 mm. They were arranged cylindrically with their long dimension vertical about the line of intersection of the two vertical ribbon beams. The detectors were equally spaced (except for beam entrances and exits) and mounted on two aluminum support rings that formed the edges of a... [Pg.185]

Two other categories of ion implanter deserve mention. First, the hybrid ribbon beam system is unique since the broad, unscanned ion beam does not scan off the wafer in the x-direction. Overscan does occur in the slow mechanically scanned direction, however. While offering an advantage for beam utilization, the ribbon beam must sacrifice uniformity and angle control to some degree. Second, Varian s broad beam approach utilizing nonmass-analyzed plasma doping. [Pg.231]

In the case of more than a single constant the threshold of the Fredericks transition can be determined analytically for a ribbon beam of the form P t ) =P(y) polarized along the xaxis. The equation linearized in (p r) in this case has the form... [Pg.118]

The beam of ionizing electrons is produced by thermionic emission from a resis-tively heated metal wire ox filament typically made of rhenium or tungsten. The filament reaches up to 2000 °C during operation. Some reduction of the working temperature without loss of electron emission (1-10 mA mm ) can be achieved by use of thoriated iridium or thoriated rhenium filaments. [22] There is a wide variety of filaments available from different manufactures working almost equally well, e.g., the filament can be a straight wire, a ribbon, or a small coil (Fig. 5.9). [Pg.202]

Fig. 2.8 Cleavage in the amphiboles. (A) Schematic representation of the characteristic stacked amphibole I-beams in the three-dimensional structure. A tetrahedral portion of an I-beam is labeled "silica ribbon." The octahedral portion is labeled "cation layer" and represented by solid circles. One of the possible cleavage directions (110) along planes of structural weakness is indicated by the line A-A stepped around the I-beams in the lower part of the diagram. (B) Cross section of the stacked I-beams with the directions of easy cleavage indicated. There is a lower density of bonds between I-beams in the crystallographic directions (110) and (110). These directions, parallel to the c axis and the length of the chains, are the planes of cleavage. The minimum thickness of a rhombic fragment produced through cleavage is 0.84 nm. Fig. 2.8 Cleavage in the amphiboles. (A) Schematic representation of the characteristic stacked amphibole I-beams in the three-dimensional structure. A tetrahedral portion of an I-beam is labeled "silica ribbon." The octahedral portion is labeled "cation layer" and represented by solid circles. One of the possible cleavage directions (110) along planes of structural weakness is indicated by the line A-A stepped around the I-beams in the lower part of the diagram. (B) Cross section of the stacked I-beams with the directions of easy cleavage indicated. There is a lower density of bonds between I-beams in the crystallographic directions (110) and (110). These directions, parallel to the c axis and the length of the chains, are the planes of cleavage. The minimum thickness of a rhombic fragment produced through cleavage is 0.84 nm.
All of the undamaged particles in Fig. 14 are of nearly uniform projected electron density, decreasing near the boundaries. There is no TEM evidence of internal structure. With increasing electron beam irradiation, however, all of the particles develop the well-known large differences in contrast (e.g., TE-3170 in Fig. 15) that have been attributed by some authors to folded ribbons or fibrils [1,13,14,17] and that we [4] and others [15,16] have attributed to beam damage. It is noted the particles shrink considerably during the beam damage. [Pg.104]

Surface reaction rate data were determined in independent studies in which the diffusion constraint was removed by molecular beam techniques. Predicted values for the overall reaction rate, computed by coupling this data with diffusion rates from boundary layer theory, are in excellent agreement with experimental values for ribbons and wires. [Pg.261]


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See also in sourсe #XX -- [ Pg.234 ]

See also in sourсe #XX -- [ Pg.234 ]




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Ribbons

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