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51.
A two-dimensional analytical model for channel potential and threshold voltage of short channel dual material gate lightly doped drain MOSFET 下载免费PDF全文
Shweta Tripathi 《中国物理 B》2014,(11):624-629
An analytical model for the channel potential and the threshold voltage of the short channel dual-material-gate lightly doped drain (DMG-LDD) metal-oxide-semiconductor field-effect transistor (MOSFET) is presented using the parabolic approximation method. The proposed model takes into account the effects of the LDD region length, the LDD region doping, the lengths of the gate materials and their respective work functions, along with all the major geometrical parameters of the MOSFET. The impact of the LDD region length, the LDD region doping, and the channel length on the channel potential is studied in detail. Furthermore, the threshold voltage of the device is calculated using the minimum middle channel potential, and the result obtained is compared with the DMG MOSFET threshold voltage to show the improvement in the threshold voltage roll-off. It is shown that the DMG-LDD MOSFET structure alleviates the problem of short channel effects (SCEs) and the drain induced barrier lowering (DIBL) more efficiently. The proposed model is verified by comparing the theoretical results with the simulated data obtained by using the commercially available ATLASTM 2D device simulator. 相似文献
52.
Pure and Ba2+ doped Alq3 complexes were synthesized by simple precipitation method at room temperature, maintaining stoichiometric ratio. These complexes were characterized by XRD, UV–vis and FT-IR and photoluminescence (PL) spectra. XRD analysis reveals the polycrystalline nature of the synthesized complexes, while UV and FTIR confirm the molecular structure and the completion of quinoline ring formation and presence of quinoline structure in the metal complex. PL spectra of Alq3 compared with barium doped complexes exhibit highest intensity in comparison to Alq3 phosphor, which proves that barium enhances PL emission intensity of Alq3 phosphor. The excitation spectra of the synthesized complexes are in the range of 300–480 nm with a broad peak in the range of 429–440 nm and shoulder at 380 nm, but with varying intensity. The emission wavelength lies in the range of 501–506 nm. Among all the synthesized complexes, AlBa2q5 exhibits maximum emission intensity. These remarkable properties of AlBaq5 could be considered as promising materials as optoelectronic materials as well as green light emissive materials for OLEDs, PLLCD and solid state lighting applications. 相似文献
53.
Synthesis of substituted phenanthridinones and dibenzoazepinones has been realized from 2-halo-benzamides in the presence of potassium tert-butoxide and a catalytic amount of 1,10-phenanthroline or AIBN. This new carbon-carbon bond forming reaction gives direct access to various biaryl lactams containing six- and seven-membered rings chemoselectively. Carbon-carbon coupling seems to proceed by the generation of a radical in the amide ring which leads to C-H arylation of aniline. 相似文献
54.
Infiltration of Liquid Metals in Porous Compacts: Modeling of Permeabilities During Reactive Melt Infiltration 总被引:1,自引:0,他引:1
Reactive infiltration is a fast and cost-effective technique for manufacturing ceramic-matrix composites (CMCs). CMCs are used in elevated temperature applications like rocket engine casings, jet nozzles, gas turbine blades and nuclear cladding. There is an urgent need for minimizing experimental costs as well as optimizing process parameters during manufacture, so that we have minimized manufacturing costs and reduced infiltration times. Towards this end, the objective of this research was to develop an integrated micro-macro model of reactive flow of molten silicon in a porous preform consisting of carbon-coated silicon carbide fibers and then optimize process parameters computationally. The overall objective of the research was to arrive at a modified equation of Darcy's law for flow through a porous medium with the help of numerical/computational modeling. This paper deals with the flow of silicon through porous carbon at the macro level. The macro flow of silicon was integrated with an available micro model by determining the transient porosity from the micro model and using it in Darcy's law written for the macro flow of silicon. From the results of this study, we recommend suitable process parameters such as initial temperature of the solid reactant and the specific kind of reactants to be used for achieving complete infiltration. These conclusions are drawn after observation of the rate of decrease of permeability with more reaction. 相似文献
55.
S.E. Lofland S.I. PatilS.M. Bhagat A.A. ArsenovS.G. Karabashev Y. Mukovskii 《Solid State Communications》2003,127(1):17-19
We have investigated the magnetic phase diagram of polycrystalline and single-crystal La1−xSrxMnO3 near 0.46≤x≤0.50. It turns out that for x<0.48, the polycrystalline material is ferromagnetic (FM), but for x≥0.48, incipient charge ordering takes place along with antiferromagnetism. At x=0.48, the ferromagnetic-antiferromagnetic phase transition in ceramics occurs at less than 85 kOe but requires significantly larger field for increasing x. These observations are in contrast to what is found in the single crystals, which are all FM. 相似文献
56.
57.
S.M. Bhagat D.J. Webb M.A. Manheimer 《Journal of magnetism and magnetic materials》1985,53(3):209-220
We report measurements on magnetic resonance in a number of transition metal-glass former complexes. Data were taken over a wide range of frequencies (2–35 GHz) and temperatures (2–300 K). In the ferromagnetic regime all the systems have a term in their linewidth which points strongly to noncolinearity of spin in glassy magnets even in a nominally saturated state. At low temperatures, in the reentrant alloys, there is a characteristic exponential term describing the increase in linewidth, with reducing T. Such a contribution appears in most random spin systems. There is no adequate microscopic picture to account for many of the results. 相似文献
58.
Gananadhamu Samanthula Debasish Swain Gayatri Sahu Shweta Bhagat P. V. Bharatam 《Journal of Analytical Chemistry》2018,73(6):560-569
The fixed dose combination of azilsartan medoxomil potassium and chlorthalidone has been introduced for the effective treatment of hypertension. In the present work a rapid, simple and accurate stability indicating ultra HPLC assay method has been developed. The separation of azilsartan medoxomil, chlorthalidone and their degradation products were accomplished on an Acquity UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm) column using mobile phase combination of 0.02% trifluoroacetic acid in water and acetonitrile in gradient mode. The forced degradation products were identified using liquid chromatography?electrospray ionisation-quadrupole time of flight-tandem mass spectrometry (LC?ESIQTOF–MS/MS) and accurate mass experiments. The in silico toxicities of the degradation products for both the drugs were evaluated. The proposed method was validated as per the ICH Q2 (R1) guideline for selectivity, linearity, precision, accuracy and robustness. 相似文献
59.
We describe the integration of a small-molecule hydrogen-bond-donor template into a cascade reaction that is comprised of a combination of molecular and supramolecular events. The cascade is performed mechanochemically and in the presence of μL amounts of water. The small-molecule template is generated (molecular) using water-assisted vortex grinding and is then used to assemble an alkene (supramolecular) to undergo an intermolecular [2 + 2] photodimerization reaction (molecular). The chemical cascade results in a cyclobutane photoproduct that we show serves as a building block of a hydrogen-bonded network with a topology that conforms to T-silica. Remarkably, the molecular–supramolecular–molecular chemical cascade occurs stepwise and entirely regioselectively within the continuous mechanochemical conditions employed.Mechanochemistry is applied to molecular and supramolecular chemistry to support a template-directed photochemical reaction. 相似文献
60.
Mehrotra R.C. Singh A. Bhagat M. Godhwani J. 《Journal of Sol-Gel Science and Technology》1998,13(1-3):45-49
In view of the advantages of employing heterometallic alkoxides as precursors for ceramic materials by the sol-gel process, efforts are being made to develop novel routes for their synthesis and to design single source precursors suited to the final targeted material. Three such new pathways are briefly presented in this paper: (i) varying the ratio of constituent metals; (ii) dissolution of metal chlorides in alkoxides of tetravalent metals; and (iii) reactions of acidic protons of metal glycolate derivatives with alkoxides of another metal yielding derivatives containing other alkoxometallates in cationic form. 相似文献