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In the recent sub-20 nm technology node, the process variability issues have become a major problem for scaling of MOS devices. We present a design for a strained Si/SiGe FinFET on an insulator using a 3D TCAD simulator. The impact of metal gate work function variability (WFV) on electrical parameters is studied. Such impact of WFV for different mole fractions (x) of the SiGe layer in a strained SOI-FinFET with varying grain size is presented. The results show that as the mole fraction is increased, the variability in threshold voltage (σVT) and off current (σIoff) is decreased; while, the variability of on-current (σIon) is increased. A notable observation is the distribution of electrical parameters approaches a normal distribution for smaller grain sizes.  相似文献   
3.
Ghosh  Puja  Bhowmick  Brinda 《SILICON》2020,12(5):1137-1144

This paper addresses reliability issues associated with temperature of Ferroelectric Dopant Segregated Schottky Barrier Tunnel Field Effect Transistor (Fe DS-SBTFET). The simulated results are compared with Dopant Segregated Schottky Barrier TFET (DS-SBTFET). This is achieved by varying the operating temperature from 300 to 500 K. DC parameters such as ION/IOFF ratio, drain current characteristics and subthreshold swing (SS) for a range of temperature have been highlighted. Moreover, the influence of temperature on various RF figure of merits such as gate capacitance (CGG), intrinsic delay, cutoff frequency (fT) etc. have been investigated. The device linearity has been analyzed by considering the effect of temperature variation on linearity parameters like gm2, gm3, 1-dB compression point, VIP2, VIP3 and IIP3. The device characteristics get upgraded by the increase in cut-off frequency and reduction in intrinsic delay at elevated temperature.

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4.
A new and simple method of finite-element grid improvement is presented. The objective is to improve the accuracy of the analysis. The procedure is based on a minimization of the trace of the stiffness matrix. For a broad class of problems this minimization is seen to be equivalent to minimizing the potential energy. The method is illustrated with the classical tapered bar problem examined earlier by Prager and Masur. Identical results are obtained.  相似文献   
5.
We report on the use of pulsed plasma-enhanced chemical vapor deposition (P-PECVD) technique and show that “state-of-the-art” amorphous silicon (a-Si:H) materials and solar cells can be produced at a deposition rate of up to 15 Å/s using a modulation frequency in the range 1–100 kHz. The approach has also been developed to deposit materials and devices onto large area, 30 cm×40 cm, substrates with thickness uniformity (<5%), and gas utilization rate (>25%). We have developed a new “hot wire” chemical vapor deposition (HWCVD) method and report that our new filament material, graphite, has so far shown no appreciable degradation even after deposition of 500 μm of amorphous silicon. We report that this technique can produce “state-of-the-art” a-Si:H and that a solar cell of p/i/n configuration exhibited an initial efficiency approaching 9%. The use of microcrystalline silicon (μc-Si) materials to produce low-cost stable solar cells is gaining considerable attention. We show that both of these techniques can produce thin film μc-Si, dependent on process conditions, with 1 1 1 and/or 2 2 0 orientations and with a grain size of approx. 500 A. Inclusion of these types of materials into a solar cell configuration will be discussed.  相似文献   
6.
1. Nine male volunteers were exposed to the pyrethroid insecticide cyfluthrin. The study was performed in an exposure room, where an aerosol containing cyfluthrin was sprayed to obtain atmospheres with mean cyfluthrin concentrations of 160 and 40 micrograms/m3. Four volunteers were exposed for 10, 30 and 60 min at 160 micrograms/m3 and another five volunteers were exposed for 60 min at 40 micrograms/m3. For 160 micrograms/m3 exposure urine samples were collected before and immediately after exposure as well as for the periods 1-2, 2-3, 3-4, 4-5, 5-6, 6-12 and 12-24 h after exposure. For 40 micrograms/m3 exposure urine samples were collected before and 2 h after exposure. 2. The main urinary cyfluthrin metabolites, cis-/trans-3-(2,2-dichlorovinyl)-2,2-dimethylycyclopropane carboxylic acid (DCCA) and 4-fluoro-3-phenoxybenzoic acid (FPBA), were determined. The limit of detection (LOD) for all metabolites was 0.0025 microgram in an urine sample of 5 ml (0.5 microgram/l). After inhalative exposure of 40 micrograms cyfluthrin/m3 air for 60 min, the amount of metabolites in urine collected in the first 2 h after exposure was less than the LOD, namely 0.14 microgram for cis-DCCA, 0.15-0.28 microgram for trans-DCCA and 0.12-0.23 microgram for FPBA. 3. Of the metabolites, 93% was excreted within the first 24 h (peak excretion rates between 0.5 and 3 h) after inhalative exposure of 160 micrograms/m3. The mean half-lives were 6.9 h for cis-DCCA, 6.2 h for trans-DCCA and 5.3 h for FPBA. 4. The mean trans-:cis-DCCA ratio was 1.9 for the time course as well as for each subject. 5. The amount of metabolites in urine depends on the applied dose, on the exposure time and shows interindividual differences.  相似文献   
7.
大型水电工程需要大量的开挖隧洞,作者是负责印度国家水电公司(NHPC)所属的Tessta Ⅱ级水电工程的总工程师,现对印度在水电开发中的最新隧洞开挖工程做了一个展望。  相似文献   
8.
Ground rubber tire (GRT) powder was maleated in an internal mixer using maleic anhydride and dicumyl peroxide at 160°C. Maleated GRT was characterized by using X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, wettability, and differential scanning calorimetry. The physical properties of the dynamically vulcanized 60 : 40, rubber : plastic composition based on acrylated high‐density polyethylene as the plastic phase and ethylene propylene diene rubber containing maleated GRT as the rubber phase were found to be greater than the corresponding composition containing nonmaleated GRT. The blend was found to be reprocessable, like themoplastic elastomers. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 370–378, 2002; DOI 10.1002/app.10348  相似文献   
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10.
Cladosporium herbarum grown as a surface culture in a chemically defined medium of sucrose and inorganic salts gave a high yield of fat (29.2%). The component acids of this fat have been found to be palmitic (34.2%); oleic (15.9%); linoleic (34.2%) and linolenic (15.7%). The combined proportion of linoleic and linolenic acids being about 50 per cent, the fat will be of great value for the manufacture of oil-modified resins as the films produced by such resins do not become yellow with age.  相似文献   
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