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Scaling trends of FinFET architecture, with focus on Front-End-of-Line (FEOL), and Middle-of-Line (MOL) device parameters, is systematically investigated. It is concluded that the combined requirements of device electrostatics together with the demands on contact resistance, presents a Contacted-Gate-Pitch (CGP) scaling limit for horizontal-transport FETs. FET drive is expected to significantly degrade below this CGP ~ 40 nm as a result. Good agreement between hardware data and TCAD simulations is achieved and employed to estimate the contact resistance values for aggressively scaled FinFETs. These observations show that FinFETs scaled below CGP of 40 nm will require the contact resistivity (ρ C ) of ~8 × 10 -10 Ω-cm 2 , while fully ohmic contacts i.e., ρ C of ~1 × 10 -10 Ω-cm 2 will be required if FinFETs are to extend performance below CGP of 30 nm. Ultimately, transition to new device architectures in which contact area is independent of CGP and/or Fin-Pitch will be necessary.

FinFET with contact over active-gate (COAG) is implemented on 12nm node technology platform to optimize the Maximum Oscillation Frequency $(F_{MAX})$ ) and the Minimum Noise Figure $(NF_{MIN}$ for devices with large fin numbers. This study shows that proposed COAG design can reduce the gate resistance of the 40-fin device by ~ 10- fold, while improving the $F_{MAX}$ by ~ 180% with comparable reliability performance to traditional FinFETs. Excellent DC and RF performances with $NF_{MIN}$ of 0.6dB at 26GHz and 3dB improvement in NF with $50\mathrm{Q}$ source impedance $(NF_{50}$ ) over the 5-26GHz frequency range makes large fin number COAG FinFET an excellent candidate for variety of 5G sub-6GHz and mmWave applications in which high $\mathrm{F}_{\mathrm{MAX}}$ and low noise are critical.

This article provides a comprehensive review of recent advances in heterostructures of two-dimensional (2-D) layered materials for future electronic and optoelectronic applications. We also discuss the progress in capping heterostructures, where an inert 2-D material serves as a passivation layer and provides environmental stability to the relatively unstable 2-D material. Such capping of heterostructures often enhances the electronic properties (e.g., the carrier mobility) of the active 2-D layer by orders of magnitude. Finally, we elucidate the progress in large-area growth of these heterostructures using various state-of-the-art techniques.

Neurotransmitter release in chemical synapses is fundamental to diverse brain functions such as motor action, learning, cognition, emotion, perception, and consciousness. Moreover, improper functioning or abnormal release of neurotransmitter is associated with numerous neurological disorders such as epilepsy, sclerosis, schizophrenia, Alzheimer’s disease, and Parkinson’s disease. We have utilized hysteresis engineering in a back-gated MoS2 field effect transistor (FET) in order to mimic such neurotransmitter release dynamics in chemical synapses. All three essential features, i.e., quantal, stochastic, and excitatory or inhibitory nature of neurotransmitter release, were accurately captured in our experimental demonstration. We also mimicked an important phenomenon called long-term potentiation (LTP), which forms the basis of human memory. Finally, we demonstrated how to engineer the LTP time by operating the MoS2 FET in different regimes. Our findings could provide a critical component toward the design ...

The characteristics of Stacked Nanosheet are investigated, focusing on channel geometry. For the first time, “narrow sheet effect” on carrier transport is observed. By comparing measured electron $(\mu_{e})$ and hole $(\mu_{h})$ mobilities, and the n-type/p-type opposite transconductance ( $gm$ ) trends versus sheet width ( $Wsheet$ ), we show that the mobility dependency on $Wsheet$ is attributed to reduced (100) plane conduction contribution as $Wsheet$ shrinks.

This work investigates the impact of CMOS scaling on the DC effective drive current, $I_{eff}$ [1], $I_{eff}=1/2\times(I_{high}+I_{low})=1/2\times [d_{s}(V_{gs}=0.5V_{dd},V_{ds}=V_{dd})+(V_{gs}=V_{dd},V_{ds}=V_{dd}/2)$ ] of aggressively scaled MOSFETs down to 7nm node technology. FinFET and Nanosheet (NSFET) architectures [2], [3] behave similarly, and $l_{eff)}$ continues to predict the intrinsic delay for aggressively scaled MOSFETs for both device architectures, even for supply-voltages $(V_{dd})$ as low as ~0.2V, where these devices operate in the subthreshold regime. The ratio of $l_{eff}/I_{on}, I_{on}=I_{ds}(V_{ds}=V_{gs}=V_{dd})$ , as a function of $V_{dd}$ , and threshold voltage $(V_{th})$ ) show that this ratio can be significantly modulated about a typical value of ~0.5, in a manner that can be easily related to classical MOSFET behavior.

Doped hafnia ferroelectric layers with thicknesses from 3 to 8nm are integrated into state-of-the-art 14nm FinFET technology without any further process modification. Ferroelectric devices show improved subthreshold slope (as low as 54mV/dec) and I dsat (up to 165% increase). C-V curves show slight ferroelectric hysteresis. For the first time, we show that ring oscillators with ferroelectric devices can operate at frequencies similar to regular dielectrics, while improved subthreshold slope reduces their active power. We also propose a model for ferroelectric MOSFETs that spans both negative (NCFET) and positive (PCFET) ferroelectric capacitance (CFE) devices. By carefully designed capacitance matching ferroelectric devices can provide significant power savings without sacrificing the speed.

Hysteretic switching with a sub-kT/q steep slope (13 mV/decade at room temperature) is experimentally demonstrated in MOSFETs with PbZr0.52Ti0.48O3 as a ferroelectric (FE) gate insulator, integrated on a silicon channel with a nonperovskite high-k dielectric (HfO2) as a buffer interlayer. The steep switching is independent of drain bias. For the first time, sub-kT/q switching due to FE negative capacitance is observed not at low currents, but in strong inversion (Id ~ 100 μA/μm). Steep switching in strong inversion provides an important point of consistency with the predictions of the Landau-Devonshire theory and the Landau-Khalatnikov equation.

In this paper, the recent trend of the worldwide wind energy utilisation is reviewed and the recent activities in using renewable energy sources in Iran are explained. As a case study, the wind characteristics of the province of Sistan and Baluchestan are statistically analysed. The wind characteristics such as the monthly mean wind speed and the wind power density of each station are presented. The monthly variation of the wind direction is presented and also the dominant wind direction is shown in a wind rose diagram. The values of turbulence intensity at different heights are calculated. The results show that the stations of Khash and Nosratabad are more suitable for limited off-grid utility applications. Lootak with the average annual wind power density of 388 W m−2 at the height of 40 m and constant wind direction is recommended for large-scale grid-connected wind turbines.

The FinFET architecture, introduced at the 22nm node [1], has delivered improved MOSFET electrostatics, which has enabled gate-length (L Gate ) scaling down to 48nm Contacted Gate Pitch (CPP) at the 7nm node [2], [3] (Fig. 1). Enhanced performance gains have been realized via the ‘Fin Effect’ (W eff /Fin-Pitch) boost, which provides improved drive current for a given capacitive load. However, limits on the Fin thickness are quickly being approached and will soon limit further L Gate scaling, resulting in accelerated reduction in source/drain sizes vs. CPP. The combination of increasing Fin Effect and a plateau in the L Gate place extreme pressure on the vertical conduction path from contacts to source and drain. With current values of contact resistivity (pc) for metal-to-degenerately-doped silicon of ∼2×10−9 [4] FinFET performance will significantly deteriorate below CPP of ∼40nm, while a theoretical fully ohmic floor of ∼1×10−10Ω-cm2 [5] could push the CPP limit to below 30nm. We conclude that there will be severe pressure for the industry to adopt a new device architecture or scaling option in the 30–40nm CPP region to carry on the power/performance benefits of CMOS scaling.

Nanosensor arrays have recently received significant attention due to their utility in a wide range of applications, including gas sensing, fuel cells, internet of things, and portable health monitoring systems. Less attention has been given to the production of sensor platforms in the μW range for ultra-low power applications. Here, we discuss how to scale the nanosensor energy demand by developing a process for integration of nanowire sensing arrays on a monolithic CMOS chip. This work demonstrates an off-chip nanowire fabrication method; subsequently nanowires link to a fused SiO2 substrate using electric-field assisted directed assembly. The nanowire resistances shown in this work have the highest resistance uniformity reported to date of 18%, which enables a practical roadmap towards the coupling of nanosensors to CMOS circuits and signal processing systems. The article also presents the utility of optimizing annealing conditions of the off-chip metal-oxides prior to CMOS integration to avoid limitations of thermal budget and process incompatibility. In the context of the platform demonstrated here, directed assembly is a powerful tool that can realize highly uniform, cross-reactive arrays of different types of metal-oxide nanosensors suited for gas discrimination and signal processing systems.

Neurotransmitter release in chemical synapses is fundamental to diverse brain functions such as motor action, learning, cognition, emotion, perception, and consciousness. Moreover, improper functioning or abnormal release of neurotransmitter is associated with numerous neurological disorders such as epilepsy, sclerosis, schizophrenia, Alzheimer's disease, and Parkinson's disease. We have utilized hysteresis engineering in a back-gated MoS

The flow of two-dimensional buoyant drops in a horizontal channel is studied by numerical simulations at finite Reynolds numbers. A linear shear flow is assumed inside the channel. The study is similar to that performed by Zhang and Campbell in granular flow regime (Zhang and Campbell in J Mech 237:541–568, 1992). The areal fraction is relatively large (0.72), and the flow is studied as a function of the bulk Reynolds number, a Reynolds number defined based on the acceleration due to gravity, and the capillary number. It is found that for a single drop motion the drop obtains an equilibrium position inside the channel. The equilibrium position is validated by comparing with other efforts. Results at a high areal fraction are compared to the work by Zhang and Campbell. The average velocity profile across the channel is relatively different compared to granular flow regime. The average fluctuation energy shows similar trends across the channel. The fluctuation energy is significantly lower on the average in the present study. The average normal stress (load) is also lower compared to granular flow regime. It is expected that this is due to the effect of interstitial fluid present in the present study.

Ruta graveolens L. is a flavonoid-containing medicinal plant with various biological properties. In the present study, the effects of R. graveolens extract on aldehyde oxidase, a molybdenum hydroxylase, are investigated. Aldehyde oxidase was partially purified from liver homogenates of mature male guinea pigs by heat treatment and ammonium sulphate precipitation. The total extract was obtained by macerating the aerial parts of R. graveolens in MeOH 70% and the effect of this extract on the enzyme activity was assayed using phenanthridine, vanillin and benzaldehyde as substrates. Quercetin and its glycoside form, rutin were isolated, purified and identified from the extract and their inhibitory effects on the enzyme were investigated. R. graveolens extract exhibited a high inhibition on aldehyde oxidase activity (89-96%) at 100 microg/ml which was comparable with 10 microM of menadione, a specific potent inhibitor of aldehyde oxidase. The IC50 values for the inhibitory effect of extract against the oxidation of benzaldehyde, vanillin and phenanthridine were 10.4, 10.1, 43.2 microg/ml, respectively. Both quercetin and rutin at 10 microM caused 70-96% and 27-52% inhibition on the enzyme activity, respectively. Quercetin was more potent inhibitor than rutin, but both flavonols exerted their inhibitory effects mostly in a linear mixed-type.

Nanowire (NW) transistors have been suggested as logical replacements for their planar metaloxide-semiconductor field-effect transistor (MOSFET) counterparts for future generation technologies. During the past decade, devices fabricated using NW geometries have shown intrinsic performance benefits such as reduced carrier scattering and the potential to operate in or close to the quantum capacitance limit (QCL), owing to their nanoscale dimensions and ability to fabricate gate-all-around (GAA) architectures for improved electrostatics. Ge/Si as a material choice is particularly attractive in this respect as it is not only easy to fabricate compared to the spectrum of available materials, but also because the type II staggered band alignment that arises between the two materials in a core/shell NW arrangement yields further performance enhancements inaccessible to homogenous NW systems. A major benefit of this architecture is a long carrier mean free path of ~500nm at room temperature, a necessary ingredient for easily accessing the ballistic transport regime. To date, Ge/Si NWFETs have experimentally demonstrated scaled transconductance values of 3300 μS·μm, on-current levels in the 2000 μA·μm range, and intrinsic switching delays of ~4ps that outperform state-of-the-art MOSFETs.

The objective of this research was to determine chemical composition and microbiological quality of the Bonab kebabs sold in the Tabriz market. In the chemical analysis, pH, moisture, protein, fat and salt contents, as well as some minerals such as Na, K, Fe and Cu were determined both for raw and cooked samples. The samples were examined for aerobic plate count (APC), coliforms, mold and yeast, Clostridium perfringens and Salmonella spp. to observe the hygienic quality of the Bonab kebabs. The results of the chemical analysis showed 5.99–6.45 pH, 66.23–56.94% of moisture, 14.3–19.59% of protein, 14.05–18.58% of fat, 2.06–2.72% of ash and 1.27–1.96% of salt values for the raw–cooked samples, respectively. The results for minerals were (mg/100 g): 0.72–1.06 Fe, 0.21–0.27 Cu, 573–745 Na and 616–913 K. The microbiological analysis showed 6.75–3.22 cfu/g APC, 5.30–1.69 cfu/g coliforms, 3.36–0 cfu/g Clostridium and 4.53–3.39 cfu/g mold and yeast for the raw–cooked samples, respectively. In conclusion, it could be proposed from the data that the Bonab kebabs sold in Tabriz market had acceptable nutritional value and hygienic quality, but future inspections are necessary for the hygenic quality of places which prepare these foods. PRACTICAL APPLICATIONS A wide range of ready-to-eat foods have been reported as a source of foodborne diseases in different countries. Because of lack of information on the incidence of foodborne diseases related to Bonab kebabs and absence of microbiological standards for this food product, the survey reported here was undertaken to explore populations and profiles of microorganisms on raw and cooked kebabs. Data reported for the first time from this study could be used to inform kebab producers and consumers of the potentially associated microbial hazards and adequate means for food protection.

Zinc deficiency is one of the most prevalent nutritional problems. In a food, phytic acid to zinc mole ratio is the main factor for determination of zinc bioavailability, therefore we measured phytic acid and its mole ratio to zinc in flour and various breads – including: Lavash, Mashini, Sangak, Oskoo, Barbari, Roghani and Baggett – which are consumed in Tabriz, Iran. The study was a descriptive, cross-sectional investigation. Mean of phytic acid and its mole ratio to zinc in flour was 262.75 (CI with 95%: 210.38–315.11 mg/100) and 19.36 (CI with 95%: 14.93–23.79), respectively. For the breads above indices were 108.53 (CI with 95%: 93.75–123.31 mg/100) and 8.91 (CI with 95%: 7.76–10.06), respectively. The differences between breads’ phytic acid and its mole ratio to zinc with those of flours were significant (p

Iron and vitamin A deficiencies are among the most prevalent nutritional problems. There are no data on iron bioavailability in Iran. In addition, interaction of vitamin A with iron bioavailability is not well documented, so we determined iron bioavailability from the most widely consumed food in Iran, lavash bread, and the effect of vitamin A on this bioavailability.In vivo human studies for determining iron bioavailability are cumbersome, time consuming, and costly to perform, so we used an in vitro model in Caco-2 cells. Bread samples were digested with or without vitamin A (10 microg/1.0 g of dried bread). We used an iron solution containing vitamin C as a positive control. Iron absorption was measured using 59FeCl3. Bioavailability was defined as the percentage of radiolabeled iron taken up and transferred by Caco-2 cells after 1.5 h of incubation. Experiments were carried out two to four times.Mean +/- standard deviations for iron bioavailability in bread samples digested without or with additional vitamin A and in controls were 2.53 +/- 1.55%, 6.62 +/- 3.40%, and 20.80 +/- 2.30%, respectively (P0.001). Vitamin A caused a 2.62-fold increase in iron absorption from bread samples.Iranian lavash bread has low iron bioavailability, but this can be increased by vitamin A supplementation. Increasing vitamin A intake can be considered as a method for increasing iron bioavailability, thus combating iron and vitamin A deficiencies simultaneously.

The effect of diameter variation on electrical characteristics of long-channel InAs nanowire metal-oxide-semiconductor field-effect transistors is experimentally investigated. For a range of nanowire diameters, in which significant band gap changes are observed due to size quantization, the Schottky barrier heights between source/drain metal contacts and the semiconducting nanowire channel are extracted considering both thermionic emission and thermally assisted tunneling. Nanowires as small as 10 nm in diameter were used in device geometry in this context. Interestingly, while experimental and simulation data are consistent with a band gap increase for decreasing nanowire diameter, the experimentally determined Schottky barrier height is found to be around 110 meV irrespective of the nanowire diameter. These observations indicate that for nanowire devices the density of states at the direct conduction band minimum impacts the so-called branching point. Our findings are thus distinctly different from bulk-type results when metal contacts are formed on three-dimensional InAs crystals.

The impact of channel material and dimensionality on the linearity of nanowire transistors is studied theoretically. This paper also evaluates various scattering mechanisms in this context. While operating under 1-D transport conditions in the quantum capacitance limit, the achievable device linearity strongly depends on the details of the scattering mechanisms limiting the transport. Interestingly, it is not only the scattering length that determines the third-order intercept point but also the particular energy dependence of the dominant-scattering mechanism that needs to be considered. Our results provide critical insights for the choice of material to obtain the desired device linearity.

Nanostructures have attracted a great deal of attention because of their potential usefulness for high density applications. More importantly, they offer excellent avenues for improved scaling beyond conventional approaches. Less attention has been paid to their intrinsic potential for distinct circuit applications. Here we discuss how a combination of 1-D transport, operation in the quantum capacitance limit, and ballistic transport can be utilized for certain RF applications. In particular this work explores how the above transport properties can provide a high degree of transconductance linearity at the device level. The article also discusses how device characteristics can be interpreted and analyzed in terms of device linearity if the above conditions are not ideally fulfilled. Using aggressively scaled silicon nanowire field-effect transistors as an example device in this work provides new insights toward the proper choice of channel material to improve linearity through the above-mentioned transport conditions. According to this study, a high degree of linearity occurs feasible while operating at low supply voltages making low-dimensional systems, and here in particular nanowires, an interesting candidate for portable RF applications.

The Bender Gestalt test of visuomotor coordination was applied to a sample of Iranian children (N = 1,600) aged between 6.0 years and 10 years and 11 months attending grades 1 through 5 of 16 public primary schools in Shiraz city, southern Iran. The administration of the test and its scoring followed the standard procedures recommended by Koppitz. The reliability of the test in its new context was investigated through readministering it to a group of 60 children after four weeks, the r being .77. The validity of the test was established by comparing scores of children at different age levels and by correlating test results with marks obtained in two sets of examinations, results of Goodenough Harris Draw-A-Person Test and indices of parental education and occupation. The results are mostly in the expected direction and indicate that the Bender Gestalt test may be used as a simple measure of cognitive-intellectual development in Iran. Observed differences between Iranian norms and those of Koppitz (1963, 1975) for American children are briefly discussed and explained.