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81.
Atoms constructing an interconnecting metal linein a semiconductor device are transported by electron flowin high density.This phenomenon is called electromigration,which may cause the line failure.In order to characterize theelectromigration failure,a comparison study is carried outwith some typical phenomena treated by fracture mechanicsfor thin and large structures.An example of thin structures,which have been treated by fracture mechanics,is silica optical fibers for communication systems.The damage growth ina metal line by electromigration is characterized in comparison with the crack growth in a silica optical fiber subjectedto static fatigue.Also a brief comparison is made betweenthe electromigration failure and some fracture phenomena inlarge structures. 相似文献
82.
Silicon carbide (SiC) is a candidate material for electronic devices to operate upon crucial environment. Electronic states of silicides and/or carbide/graphite formed in metal/SiC contact system is fundamentally important from the view point of device performance.We study interface electronic structure of vanadium (V) thin-film deposited on 6H-SiC(0 0 0 1) Si-face by using a soft X-ray emission spectroscopy (SXES). For specimens of V(38 nm)/6H-SiC (substrate) contact systems annealed at 850 °C, the Si L2,3 emission spectra indicate different shapes and peak energies from the substrate. The product of materials such as silicides and/or ternary materials is suggested. Similarly, the C Kα emission spectra show the shape and peak energy characteristic of vanadium carbide including substrate 6H-SiC signal. 相似文献
83.
Yuhao Huang Yunlong Gao Weigang He Zihao Wang Wei Li Aijun Lin Jinyi Xu Genzoh Tanabe Osamu Muraoka Xiaoming Wu Weijia Xie 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6466-6470
An efficient and divergent approach toward the synthesis of all four de‐O‐sulfonated sulfonium type α‐glucosidase inhibitors, originally isolated from plants of genus Salacia, is reported for the first time. The key strategy features a coupling reaction between thiol derivatives and a diiodide counterpart. The newly designed thiol coupling partner presents high chemical stability, while the diiodide partner could be easily obtained with increased overall yields compared with conventional routes. The intermolecular nucleophilic substitution reaction followed by a diastereoselective intramolecular cyclization provided the target five‐member sulfonium salt structure, which was connected in an α‐orientation to a polyhydroxylated side‐chain moiety. 相似文献
84.
85.
Radial distribution of electron temperature as well as that of plasma current has been measured in the skin phase in turbulent heating of a high-density plasma (n ? 2 × 1014m?3). Anomalously rapid disappearance of the current skin is observed, while the skin profile of the electron temperature remains longer near the plasma core, indicating that the plasma current is redistributed without electron heat transfer across the magnetic field. 相似文献
86.
K. Matsuo Y. Gosho T. Toyoda Y. Sonoda K. Muraoka M. Akazaki 《International Journal of Infrared and Millimeter Waves》1985,6(10):1051-1059
This paper is concerned with systematic developments of the Fraunhofer-diffraction method for studies of plasma density fluctuations in high-temperature plasmas using infrared lasers, namely (i) development of the general theory of the Fraunhofer-diffraction method, (ii) measurements of fluctuations propagating in an azimuthal direction, (iii) measurements of fluctuation intensities, and (iv) application in measurements on high-temperature plasmas. 相似文献
87.
88.
Yoshio Shibasaki Kiyoshige Fukuda 《Journal of polymer science. Part A, Polymer chemistry》1979,17(9):2947-2959
To clarify the effect of a molecular arrangement of long-chain monomers on polymerizability, γ-ray-initiated postpolymerization of polymorphic crystals of octadecyl acrylate and the melt has been investigated. According to thermal, x-ray, and infrared (IR) analyses octadecyl acrylate exhibit three crystalline modifications similar to, but different in transition behavior from, those of octadecyl methacrylate. The α-form is stable in the range of 19–32°C (mp) and at lower temperatures the β-form is stable, whereas the sub-α-form appears transiently in α → β transition. The monomer molecules in triclinic packing (α-form) show little tendency to polymerize, whereas those in hexagonal packing (β-form) have high polymerizability that increases with temperature. The polymerizability in the molten state at fairly high temperatures is rather low, however. Thus the polymerization rate, saturated conversion, and polymer molecular weight exhibit maxima just above the melting point of α-form. It is concluded that the hexagonal packing of monomer molecules with particular orientation in the layered structure and rotational freedom around the molecular axis, together with some conformational freedom of functional group, is favorable to the polymerization reaction. In addition, the mechanism of polymerization in the layered structure is discussed, assuming a cone-type distribution for the polymerization probability. 相似文献
89.
Kazuyuki Horie Atsushi Otagawa Minoru Muraoka Itaru Mita 《Journal of polymer science. Part A, Polymer chemistry》1975,13(2):445-454
The crosslinked copolymerization of methyl methacrylate with ethylene dimethacrylate (EDMA) in bulk and in toluene has been investigated by differential scanning calorimetry. The appearance of a second peak, in addition to that arising from the gel effect, noted in curves of bulk copolymerization rate (fraction of EDMA mE = 0.20) is explained by the formation of microgels during the copolymerization. With mE = 0.50–1.00, copolymerization proceeds heterogeneously at first, providing opaque microgels, which become transparent polymer in a later stage at a weight fraction of toluene wT ≦ 0.20 and independent polymer particles at wT ≧ 0.30. A diagram is given which illustrates three types of copolymerization depending on initial composition of monomers and toluene. Final conversions for mE ≦ 0.10 agree well with predictions. Copolymerization at mE ≧ 0.20 ceases because of reduction of segmental mobility due to dense network formation in microgel, though the whole system is not yet in glassy state. Data of final conversions in solution copolymerization also support the above mechanism. 相似文献
90.
C. Honda M. Maeda K. Nishimura K. Muraoka M. Akazaki 《Applied physics. B, Lasers and optics》1984,33(3):171-177
A rapid-frequency-scan dye laser was developed for the measurement of the velocity-distribution functions of impurity atoms sputtered due to the high-temperature plasma-surface interaction. In order to confirm the effectiveness of this rapid-scan technique, measurements of the Doppler profiles of Fe atoms sputtered by Ar ion-beam bombardment with energy 3 keV were performed. A scanning range of more than 40 pm at 300 nm was obtained with a spectral bandwidth of 1.5 2 pm and good linearity. Doppler profiles were determined in various scattering conditions, and excellent performance of this technique was demonstrated. The distortion error caused by line saturation was analytically discussed, and it is shown that the effect of this error is not so serious (less than 10%) even for highly saturated excitation. 相似文献