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In this paper, the scaling theory of Fin field-effect transistors (FinFET5) has been established by a 3-D analytical solution and numerical simulation of Poisson's equation in the channel region. Considering the impact of ionized dopant in channel and source/drain on the potential distribution, respectively, the 3-D Poisson's equation is analytically solved through the super- position method. Based on the analysis of the minimum channel potential, which is approximated from the evanescent mode, a useful and simple subthreshold-swing (S) model is proposed for design consideration. According to the derived scaling length, a FinFETs structure is superior in controlling short-channel effects (SCEs). A ratio of channel length to scaling length larger than three is required for optimization. Meanwhile, it is noticed that the gate material with relative dielectric constant of about ten could sufficiently suppress SCEs. [ABSTRACT FROM AUTHOR]

This article presents an improvement on the evaluation of a Green's function method proposed by Niknejad (1998) for modeling and analysis of substrate coupling in integrated circuits. By careful combination, the 64-term summation can be approximated by a four-term one. Therefore, the computational cost can be reduced. The approximation is effective for contact pairs small compared to their separations. This article also studies quantitatively how small the contact should be in order for approximation to be applicable. Numerical results show that a speed-up of over 6× could be achieved by adopting the new approach. © 2006 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2006. [ABSTRACT FROM AUTHOR]

A scalable industry-oriented, 24-element ‘2-π’ compact circuit model for on-chip RF CMOS spiral inductors is presented. It has a good accuracy up to self-resonant frequency (SRF). Two levels of modeling approaches are provided, which are: 1) the fixed model, which extracts the values of circuit elements directly from the measured S-parameters of a given device, achieving high accuracy, but no scalability and 2) the scalable model, in which circuit elements are related to the geometry (i.e., layout) through a set of formulas with model parameters calibrated upon a few testing devices. The synthesis procedure is also discussed, which includes the scalable model and a SPICE simulator as the evaluation method within the iteration loop. [ABSTRACT FROM AUTHOR]

Objective To assess the efficacy and outcome of fast-track rehabilitation (FTR) for orthopedic surgery patients. Design Randomised trial. Setting primary care. Subjects and Methods Two hundred and twenty patients undergoing orthopedic surgery under general anesthesia between November 2015 to March 2017 were randomly divided into traditional care (control, n=110) and fast-track rehabilitation (FTR, n=110) groups. Patients in the control group were given regular and routine care, while those in FTR group were cared for with multimodal rehabilitation. Demographic and data, postoperative hospital stays, surgical and general complications were assessed. Results One hour postoperative body temperature was higher in FTR group than in the control, and the incidence of restlessness, pain and 24 hour postoperative nausea and vomiting were significantly lower (P < 0.05, P < 0.01). The hospital stays were shorter following the FTR, but the difference was not statistically significant as compared with the control. Conclusion FTR can effectively reduce the complications and promote the recovery of the orthopedic patient. [ABSTRACT FROM AUTHOR]

Gate tunneling current in fully depleted, double-gate (DG) silicon-on-insultor (SOI) MOSFETs is characterized based on quantum- mechanical principles. The gate tunneling current for symmetrical DG SOI with ground-plane (t[subox] =1.5 rim and T[subsi]=5 mn) is shown to be higher relative to single-gate (bulk) MOS structure. The tunneling is enhanced as the silicon layer becomes thinner since the thinner silicon layer acts a deep quantum well. The simulated I[subG]-V[subG] of DG SOI has negative differential resistance like that of the resonant tunnel diodes at the gate bias ∼ 1.4 V. [ABSTRACT FROM AUTHOR]

As a specific inhibitor of neutrophil elastase, sivelestat sodium hydrate has primarily been used in the treatment of acute lung injury caused by various factors since its approval in 2002. Sivelestat sodium hydrate also improves post-traumatic knee osteoarthritis (KOA), although its underlying mechanisms of action have yet to be elucidated. The aim of the current study was to determine if sivelestat sodium hydrate improves post-traumatic KOA through nuclear factor (NF)-κB in a rat model. Treatment with sivelestat sodium hydrate significantly inhibited the induction of structural changes and significantly increased the vertical episode count and ipsilateral static weight bearing of the joint in KOA rats (all P<0.01). Sivelestat sodium hydrate significantly inhibited tumor necrosis factor-a and interleukin-6 production, serum nitrite levels, inducible nitric oxide synthase protein expression and high mobility group box 1 (HMGB1) secretion in KOA rats compared with the model group (all P<0.01). Sivelestat sodium hydrate also significantly suppressed p50/p65 DNA binding activity and NF-κB and phosphorylated inhibitor of κB protein expression in the joints of KOA rats compared with the model group (all P<0.01). These results suggest that sivelestat sodium hydrate improves post-traumatic KOA through HMGB1 and NF-κB in rats. [ABSTRACT FROM AUTHOR]

INTRODUCTION This study was conducted to explore the characteristics and risk factors of e-cigarette use in adolescents, aiming for tobacco control and reducing e-cigarette use in this population. METHODS Using 1:1 matching, 88 students from three vocational high schools in Shanghai were recruited to conduct a case (using e-cigarettes) - control (not using e-cigarettes) study. Group interviews and questionnaire surveys were used for this qualitative and quantitative mixed-methods study. The keywords were extracted from the interview data and analyzed by the Colaizzi seven-step method. RESULTS The characteristics of adolescents' use of e-cigarettes include young age at first use, consumption of a large amount, as well as smoking in discrete locations in order to hide from adults. The reasons for using e-cigarettes include curiosity and wanting to replace traditional cigarettes. The risk factors of using e-cigarettes include insufficient understanding of the harm of e-cigarettes at the individual level (The positive outcome expectancy points: Z= -3.746, p<0.001; The negative outcome expectancy points: Z= -3.882, p<0.001), peer influence at the interpersonal level (χ²=6.510, p<0.01), and the influence of social and environmental factors such as e-cigarette sales in the stores and WeChat Moments (p<0.05 for all associations). CONCLUSIONS Having friends who use e-cigarettes, curiosity and sales exposure about e-cigarettes are important factors affecting the use of e-cigarettes by adolescents. It is necessary to strengthen the publicity of the potential hazards of e-cigarettes and to reduce overall usage by improving relevant laws and regulations. [ABSTRACT FROM AUTHOR]

Presents results of two-dimensional simulations of metal-oxide-semiconductor devices. Importance of quantum mechanical modeling of the entire device structure; Analysis of double and single-gated fully-depleted silicon-on-insulator devices; Comparison of density gradient results.

Finite element simulation has been employed as a promising method in the analysis of piezoelectric active devices. It is desirable to obtain results consistent with experiments for real devices. In this paper, precise geometry models of quartz resonators were generated from direct measurements of practical devices and meshed. Realistic quartz blanks, electrodes, and mountings were included in the models. An application-specified 3-D finite element simulator was developed to perform the modal analysis of realistic crystal resonators. Using the model and simulator, real devices were simulated. Simulation results, including modal analysis and temperature properties, were shown in consistency with experimental measurements. The dependencies of device performance on practical factors were studied. [ABSTRACT FROM AUTHOR]

An efficient algorithm for extraction of three-dimensional (3-D) capacitance on multilayered and lossy substrates is presented. The new algorithm presents a major improvement over the quasi-3-D approach used in a Green's function-based solver and takes into consideration the sidewalls of 3-D conductors. To im- prove the efficiency of the computation and the transformation of the Green's function, a nonuniform grid is adopted. The most computationally intensive part in the transformation of the Green's function is computed separately as technology-independent matrices Tk foremost. Once computed, Tk can be stored and used for any technology, thus the storage requirement and computational complexity are reduced from ...(S²) and ...(S² log S²), respectively, to just O[(log Smax)²]. Extensive tests have been performed to verify the new algorithm, and its accuracy has been established by comparing with other programs. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, an approach to modeling the tunneling current along the channel, i.e. the 2D quantum mechanical (QM) effects, on the charge distribution in the carrier confinement direction is developed using the concept of “locality” and the analytical solution to the 2D Poisson equation. Then, another approach, which is the gate-capacitance-shift (GCS) approach, is described. This approach is developed for the physical effects in decanano-scaled MOSFETs that have gate-bias-dependent nature, e.g. QM effects in polysilicon gates (poly-gates). Based on this approach, the QM effects in poly-gates are considered based on the density gradient (DG) formulation. Based on the above two corrections, a unified analytical charge model is established, which yields satisfactory results compared with numerical results under different device parameters. It is further embedded into a compact ballistic model for sub-100-nm MOSFETs. It is concluded that the 2D-QM effects on the threshold voltage are non-negligible through comparison to the experimental data of a 45nm MOSFET from TSMC [TSMC 45nm MOSFET, internal documentation]. [Copyright &y& Elsevier]

Discusses the influence of gate direct tunneling current on ultrathin gate oxide metallic oxide semiconductors (MOS). Analysis of the effect of gate direct tunneling current in oxide scaling; Comparison between the I[subgate] limit of the international technological roadmap for semiconductors (ITRS); Significance of a dual-gate oxide process in device scaling.

A monolithicdouble-balanced graphene mixer integrated circuit (IC) has been successfullydesigned and fabricated. The IC adopted the cross-coupled resistivemixer topology, integrating four 500 nm-gate-length graphene field-effecttransistors (GFETs), four on-chip inductors, and four on-chip capacitors.Passive-first-active-last fabrication flow was developed on 200 mmCMOS wafers. CMOS back-end-of-line processes were utilized to realizemost fabrication steps followed by GFET-customized processes. Testresults show excellent output spectrum purity with suppressed radiofrequency (RF) and local oscillation (LO) signals feedthroughs, andthird-order input intercept (IIP3) reaches as high as 21 dBm. Theresults are compared with a fabricated single-GEFT mixer, which generatesIIP3 of 16.5 dBm. Stand-alone 500 nm-gate-length GFETs feature cutofffrequency 22 GHz and maximum oscillation frequency 20.7 GHz RF performance.The double-balanced mixer IC operated with off-chip baluns realizinga print-circuit-board level electronic system. It demonstrates graphene’spotential to compete with other semiconductor technologies in RF front-endapplications. [ABSTRACT FROM AUTHOR]

An analytical model for the forming process of conductive-bridge resistive-switching random-access memory is developed. The measurable forming time can be calculated using this model giving the biasing condition and is verified to be correct through comparison with the experimental data. The forming time has been shown to have multiple-slopes in exponential dependence on the applied voltage, in agreement with measurement. The model is based on the identification of three steps in the forming process: 1) metal oxidation at the anode; 2) cation migration toward the cathode; and 3) backward filament growth due to electroplating from the cathode. The accuracy of the model has also been established via numerical simulation. [ABSTRACT FROM PUBLISHER]

In this Letter, a comprehensive analysis of how the metallic behavior transition to hopping was presented by studying the transport mechanisms of low resistance states (LRS) in Ta2O5-x/TaOy resistive switching devices at very low temperatures. Three types of conduction behaviors were reported through temperature-dependent measurements ranging from 5 K to 250 K. Memory cells at low LRS show metallic behavior due to the formation of metallic filament. The temperature dependence of resistance at medium LRS exhibits an interesting phenomenon that a positive temperature coefficient transfers into a negative one at temperature of 20 K. Detailed analysis reveals that this phenomenon is caused by the coexistence of extended and localized states, with metallic conduction at higher temperatures and variable-range hopping at lower temperatures. Carrier transport at high LRS is dominated by electrons hopping conduction with nearest-neighboring hopping conduction changing into variable-range hopping as temperature decreases. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) integration and multi-level cell (MLC) are two attractive technologies to achieve ultra-high density for mass storage applications. In this work, a three-layer 3D vertical AlOδ/Ta2O5-x/TaO5 resistive randomaccessmemories were fabricated and characterized. The vertical cells in three layers show good uniformity and high performance (e.g. .1000X HRS/LRS windows, .1010 endurance cycles, .104 s retention times at 125°C). Meanwhile, four level MLC is demonstrated with two operation strategies, current controlled scheme (CCS) and voltage controlled scheme (VCS). The switching mechanism of 3D vertical RRAM cells is studied based on temperature-dependent transport characteristics. Furthermore, the applicability of CCS and VCS in 3D vertical RRAM array is compared using resistor network circuit simulation. [ABSTRACT FROM AUTHOR]

In this Letter, the origins of current fluctuations of Al/AlOx/WOy/W bilayer resistive random access memory (RRAM) devices are investigated through detailed noise analysis. Random telegraph noise (RTN) measurements were performed on RRAMs with three different resistance states. An obvious RTN signal with 40.7% amplitude difference was found at high resistance state, and the trapping/de-trapping process leading to the RTN signal was studied in detail by extracting the trap energy from energy diagram. For median and low resistance states, the resistance fluctuations were 34.0% and 0.3%, respectively. To further study the RTN characteristics, the normalized power spectral density (PSD) was analyzed. It is found that, for one dominant-trap caused RTN phenomena, the normalized noise PSD behaves as 1/f² on the high resistance state; while for median and low resistance states, the noise follows 1/f rule, suggesting that the current fluctuations are associated with the envelop of multiple RTNs caused by traps located near/in the conductive filament. Based on the noise analyses in time and frequency domains, a conduction mechanism is proposed to describe the trap effects on the current fluctuations of different resistance states. [ABSTRACT FROM AUTHOR]

Background: The replacement of sucrose with HFCS in food products has been suggested as playing a role in the development of obesity as a public health issue. The objective of this study was to examine the effects of four equally hypocaloric diets containing different levels of sucrose or high fructose corn syrup (HFCS). Methods: This was a randomized, prospective, double blind trial, with overweight/obese participants measured for body composition and blood chemistry before and after the completion of 12 weeks following a hypocaloric diet. The average caloric deficit achieved on the hypocaloric diets was 309 kcal. Results: Reductions were observed in all measures of adiposity including body mass, BMI,% body fat, waist circumference and fat mass for all four hypocaloric groups, as well as reductions in the exercise only group for body mass, BMI and waist circumference. Conclusions: Similar decreases in weight and indices of adiposity are observed when overweight or obese individuals are fed hypocaloric diets containing levels of sucrose or high fructose corn syrup typically consumed by adults in the United States. [ABSTRACT FROM AUTHOR]

It was experimentally and numerically indicated that both the valley splitting and effective-mass variation contribute to the stress-induced enhancement of electron mobility in the MOSFET channel. In this paper, an analytical electron-mobility model for arbitrarily strained silicon is presented. The electron-mobility model includes the strain effects of both the effective-mass variation and valley degeneration. The expression of strained conduction band used in the analytical model is based on the k · p theory and accords well with numerical results of nonlocal empirical pseudopotential method (EPM). By using the mobility model, mobilities under different stresses are investigated. [ABSTRACT FROM AUTHOR]

A new compact circuit model for differential spiral transformers in CMOS radio frequency integrated circuits (RFICs) is developed in this paper. The model consists of two coupled ‘2-π’ subcircuits for each inductor coil in the transformer. All the values of the circuit elements can be analytically calculated according to the process parameters and the device's geometric dimensions, making the model highly scalable and predictive. The model has very good accuracy as validated by comparison to a 2.5-dimensional full-wave numerical electromagnetic field solver. [ABSTRACT FROM AUTHOR]

Discusses the impact of gate geometry and dopant distributions on polydepletion effects based on two- and three-dimensional device simulations. Dopant profile effects on polydepletion; Gate geometric effects on polydepletion; Polydepletion effect for small-geometry devices.

In this paper, we perform a modeling and simulation study on strained armchair graphene nanoribbon (AGNR). Two uniaxial strain models based on a tight binding method are compared with results from first-principles calculation. Tunneling field effect transistors (TFETs) with channels made of strained AGNR of different widths are modeled and simulated by a ballistic quantum transport model based on nonequilibrium Green’s function and nonparabolic effective mass approximation. Compared with TFETs with narrow AGNR, those with strained wide AGNR can achieve better device performance. [ABSTRACT FROM AUTHOR]

This paper studies the coating geometries of metals on single-walled carbon nanotubes (SWNTs) on the basis of the nucleation theory and wetting theory. The metal surface energy, cohesion energy, diffusion barrier, and metal-SWNT interfacial energy are calculated using first-principles calculation. Metals including Fe, Al, Au, Pd, Ni, and Ti are considered. For Ti, Ni, and Pd, low metal-SWNT interfacial energies and high diffusion barriers are responsible for forming continuous or quasicontinuous layers on the SWNT surface. In contrast, Al and Au have small diffusion barriers and poor SWNT surface wetting, thus they tend to aggregate and form large clusters. Although the binding energy between Fe and SWNTs is large, due to the large cohesion energy and poor wetting, Fe may form isolated clusters. All results are in good agreement with experimental observations. [ABSTRACT FROM AUTHOR]

Metal-graphene contacts play a critical role in graphene-based electronics. It is found through first-principles calculation of contacts between graphene and 12 different metals that there exist two types of contacts depending on the strength of interaction between d-orbitals in metals and pz-orbitals in graphene. Fermi level shift in the contacted graphene from the freestanding one is investigated, and the electronic structure and electrostatic potential are calculated. The carrier transport through these contacts is calculated using the extended Hückel theory-based non-equilibrium Green’s function formalism, and one type of contact is shown to have less contact resistance than the other. [ABSTRACT FROM AUTHOR]

Schottky barrier (SB) formation at the contact interface between metal and semiconducting carbon nanotubes (CNTs) is of great importance in determining the transport characteristics of a CNT field effect transistor. In this paper, we studied the SB height (SBH) between different metals and CNT contacts using first-principles calculation. A method to calculate SBH is proposed based on the interface dipole effect, which will induce an electrical potential variation at the metal and CNT interface. The SBH of a metal and CNT contact could then be determined by the work function difference between the metal and CNT and the electrical potential variation. We extensively investigated different contacts between Sc, Al, Pd, (8,0) CNT, and (11,0) CNT. The calculated SBHs for these contacts are all in good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Stable self-compliance property was observed in the AlOδ/Ta2O5−x/TaOy triple-layer resistive random access memory structure. The impact of AlOδ barrier layer was studied with different thicknesses. Endurance of more than 1010 cycles and data retention for more than 3 h at 125 °C were demonstrated. All the measurements were carried out without external current compliance and no hard breakdown was observed. Systematic analysis reveals the self-compliance property is due to the built-in series resistance of the thin AlOδ barrier layer. A model is proposed to explain this self-compliance property. [ABSTRACT FROM AUTHOR]