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1.
In this investigation, the crystalline structure of a nanometric CoSi2 layer, formed in heat treated Co/WxTa(1−x)/Si(1 0 0) systems, has been studied by XRD analysis. Careful measurements of the diffraction intensities revealed that temporary formation of a metastable diamond cubic structure of CoSi2 phase, rather than its usual CaF2 structure, was occurred. It has been shown that formation of this metastable structure depends on the kind of the applied interlayer in addition to the annealing temperature. Among the studied systems with x = 0, 0.25, 0.5, 0.75 and 1, the second and the last systems resulted in growing a (1 0 0) single-texture CoSi2 layer with the preferred usual CaF2 structure, a strained lattice parameter, and the best thermal stability (900-1000 °C). 相似文献
2.
In this work, we have studied thermal stability of nanoscale Ag metallization and its contact with CoSi2 in heat-treated Ag(50 nm)/W(10 nm)/Co(10 nm)/Si(1 0 0) multilayer fabricated by sputtering method. To evaluate thermal stability of the systems, heat-treatment was performed from 300 to 900 °C in an N2 ambient for 30 min. All the samples were analyzed by four-point-probe sheet resistance measurement (Rs), Rutherford backscattering spectrometry (RBS), X-ray diffractometry (XRD), and atomic force microscopy (AFM). Based on our data analysis, no interdiffiusion, phase formation, and Rs variation was observed up to 500 °C in which the Ag layer showed a (1 1 1) preferred crystallographic orientation with a smooth surface and Rs of about 1 Ω/□. At 600 °C, a sharp increase of Rs value was occurred due to initiation of surface agglomeration, WSi2 formation, and interdiffusion between the layers. Using XRD spectra, CoSi2 formed at the Co/Si interface preventing W silicide formation at 750 and 800 °C. Meantime, RBS analysis showed that in this temperature range, the W acts as a cap layer, so that we have obtained a W encapsulated Ag/CoSi2 contact with a smooth surface. At 900 °C, the CoSi2 layer decomposed and the layers totally mixed. Therefore, we have shown that in Ag/W/Co/Si(1 0 0) multilayer, the Ag nano-layer is thermally stable up to 500 °C, and formation of W-capped Ag/CoSi2 contact with Rs of 2 Ω/□ has been occurred at 750-800 °C. 相似文献
3.
Ali A. Moshfegh Effat Beladi Lida Radnia Afsaneh S. Hosseini Soosan Tofigh Gholam H. Hakimelahi 《Helvetica chimica acta》1982,65(4):1264-1270
The synthesis of the title compounds ( 1 and 3 ) is described. Some of the compounds prepared were found to be active against a number of pathogenic microorganisms in vitro. Structure-activity relationship is briefly discussed. 相似文献
4.
A. Poghossian S. Ingebrandt M.H. Abouzar M.J. Schöning 《Applied Physics A: Materials Science & Processing》2007,87(3):517-524
The possibilities and limitations of a direct electrical detection of charged macromolecules using a field-effect-based sensor
platform is evaluated, mainly focusing on capacitive EIS (electrolyte-insulator-semiconductor) devices. The experimentally
obtained results on the detection of DNA immobilisation and hybridisation as well as the monitoring of layer-by-layer adsorbed
charged polyelectrolyte (PE) multilayers have been discussed by using two basic possible mechanisms of signal generation,
namely the intrinsic charge of the macromolecules and the charge redistribution within the intermolecular spaces or in the
multilayer. The effects of the layer-by-layer adsorption conditions (unbuffered and pH buffer solution), and the number and
polarity of charged layers on the sensor response have been systematically investigated by means of capacitance–voltage (C–V),
constant–capacitance (ConCap) and impedance spectroscopy (IS) methods.
PACS 82.47.Rs; 82.80.Fk; 85.30.Tv; 87.15.Kg; 87.14.Gg 相似文献
5.
Thermal stability of Ag layer on Ti coated Si substrate for different thicknesses of the Ag layer have been studied. To do this, after sputter-deposition of a 10 nm Ti buffer layer on the Si(1 0 0) substrate, an Ag layer with different thicknesses (150-5 nm) was sputtered on the buffer layer. Post annealing process of the samples was performed in an N2 ambient at a flow rate of 200 ml/min in a temperature range from 500 to 700 °C for 30 min. The electrical property of the heat-treated multilayer with the different thicknesses of Ag layer was examined by four-point-probe sheet resistance measurement at the room temperature. Phase formation and crystallographic orientation of the silver layers were studied by θ-2θ X-ray diffraction analysis. The surface topography and morphology of the heat-treated films were determined by atomic force microscopy, and also, scanning electron microscopy. Four-point- probe electrical measurement showed no considerable variation of sheet resistance by reducing the thickness of the annealed Ag films down to 25 nm. Surface roughness of the Ag films with (1 1 1) preferred crystallographic orientation was much smaller than the film thickness, which is a necessary condition for nanometric contact layers. Therefore, we have shown that the Ag layers with suitable nano-thicknesses sputtered on 10 nm Ti buffer layer were thermally stable up to 700 °C. 相似文献
6.
7.
The synthesis of the title compounds is described. Some of the compounds prepared were found to be active against a number of pathogenic microorganisms in vitro. 相似文献
8.
Pure titania porous layers consisted of anatase and rutile phases, chemically and structurally suitable for catalytic applications, were grown via micro-arc oxidation (MAO). The effect of applied voltage, process time, and electrolyte concentration on surface structure, chemical composition, and especially photocatalytic activity of the layers was investigated. SEM and AFM studies revealed that pore size and surface roughness of the layers increased with the applied voltage, and the electrolyte concentration. Moreover, the photocatalytic performance of the layers synthesized at medium applied voltages was significantly higher than that of the layers produced at other voltages. About 90% of methylene blue solution was decomposed after 180 min UV-irradiation on the layers produced in an electrolyte with a concentration of 10 g l−1 at the applied voltage of 450 V. 相似文献
9.
Samadi Morasae Zirak Mohammad Naseri Amene Kheirabadi Malihe Ebrahimi Mahdi Moshfegh Alireza Z. 《Research on Chemical Intermediates》2019,45(4):2197-2254
Research on Chemical Intermediates - Photocatalysis using semiconductors has emerged as a promising wastewater treatment process to overcome the major challenges faced by conventional technologies.... 相似文献
10.
The properties of asymmetric nuclear matter for a wide range of densities and asymmetric parameters are investigated within
the lowest-order-constrained variational (LOCV) method by employing the relativistic Hamiltonian with a potential which has
been fitted relativistically to N-N phase shifts ( [(v)\tilde]14 \tilde{{v}}_{{14}}^{} and to the AV14interaction. Like our previous work on symmetric nuclear matter, the boost interaction corrections as well as the relativistic
one-body and two-body kinetic corrections are calculated. The various properties of asymmetric nuclear matter such as the
symmetry energy, the saturation energy and the validity of the a2 \alpha^{2}_{} law, etc., are examined. The symmetry energy is reduced by about 7MeV when we use [(v)\tilde]14 \tilde{{v}}_{{14}}^{} instead of its non-relativistic version, i.e. the AV14interaction. The results are compared with other many-body calculations. 相似文献