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21.
Lattice strains around a platelet oxygen precipitate in Si wafer is studied by energy filtering convergent-beam electron diffraction (CBED) and calculations based on the finite element method (FEM). Local lattice strains are measured from CBD patterns obtained with a probe size less than 2 nm in a specimen thicker than 450 nm. Strains measured are compressive along a direction normal to a plate of the precipitation and tensile along a direction parallel to the plate. Two-dimensional stress fields near the precipitate are obtained with FEM computer analyses by fitting the measured strains. It appears that shear stresses are concentrated at the end of the precipitate edge and the maximum shear stress at an interface between the precipitate and the Si-matrix is 1.9 GPa. It is demonstrated that a combination of the energy filtering CBED and FEM is very useful for the study of local strains near interfaces in semiconductor devices, in particular for the study of stress fields that are too steep for application of the conventional CBED technique.  相似文献   
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Experimental observations for possible presence of 4f quadrupolar Kondo effect in PrCu2Si2 are critically discussed. A comparison of the low temperature properties of the alloys, Pr x Y1–x Cu2Si2 (x=0.05, 0.2 and 0.4), seems to signal the existence of 4f electric quadrupolar glass phenomenon around 4K forx=0.2.  相似文献   
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We compute the cyclic homology of the coordinate ring A(SLq(2)) of the quantum algebraic group SL q (2). We observe a degeneration of the noncommutative de Rham complex. The results are also verified from the point of view of Connes' noncommutative differential geometry.  相似文献   
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From the analysis of the permeation of 35S labeled ethanesulfonic acid, through nylon-6 films sorption isotherms were obtained. The films are characterized by their largely different content of carboxyl and amino end groups. It was found that the shape of the isotherm depends on the molar ratio of the two end groups: an S-shape curve for the film containing the carboxyl end group larger than the amino end group and a Langmuir-type curve for the film containing comparable numbers of end groups. These results were explained by the McGregor-Harris theory in which the acid dissociation constants of the two end groups in nylon were estimated experimentally.  相似文献   
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In the title complex, (C6H11N2)3[LaCl6], centrosymmetric octahedral hexa­chloro­lanthanate anions are located at the corners and face‐centers of the monoclinic unit cell. The ring H atoms of the cations interact with the Cl atoms of the anions via hydrogen bonding, and bifurcation of the hydrogen bonding is observed. Cation–cation interactions via hydrogen bonding between the ring H atoms and π‐electrons of aromatic rings are also observed as in other imidazolium salts.  相似文献   
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A new technique for preparing anti-reflection/anti-static thin films for CRTs at low temperature has been developed. Double-layered films of SiO2/SnO2 were formed on a CRT panel surface by the sol-gel method using photoirradiation. The new method makes it possible to reduce heat treatment temperature (°C) by almost 50% and treatment time to approximately 33% of the conventional levels.  相似文献   
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