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Nanotechnology, IEEE Transactions on

Issue 3 • Date May 2012

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Displaying Results 1 - 25 of 37
  • [Front cover]

    Publication Year: 2012 , Page(s): C1
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  • IEEE Transactions on Nanotechnology publication information

    Publication Year: 2012 , Page(s): C2
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  • Table of contents

    Publication Year: 2012 , Page(s): 429 - 430
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  • A Low-Power 40-Gb/s 1:2 Demultiplexer IC Based on a Resonant Tunneling Diode

    Publication Year: 2012 , Page(s): 431 - 434
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (526 KB) |  | HTML iconHTML  

    A low-power 1:2 demultiplexer (DEMUX) IC based on a resonant tunneling diode (RTD) is proposed. In order to achieve low-power consumption, the unique negative differential resistance (NDR) characteristics arising from the quantum effect of the RTD are exploited. The proposed DEMUX IC consists of an return to zero (RZ)-mode 1:2 demultiplexing block and an RZ-to-nonreturn to zero converting block, which have a compact structure based on the NDR-based circuit topologies. By implementing the proposed IC using an InP RTD/heterojunction bipolar transistor monolithic microwave integrated circuit technology, 1:2 demultiplexing operation up to 40 Gb/s has been achieved with low-power consumption of 61 mW. In addition, the result is the first demonstration of a 40-Gb/s-level current-mode-logic-type DEMUX IC based on the NDR topology. View full abstract»

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  • High Current Gain Microwave Performance of Organic Metal-Base Transistor

    Publication Year: 2012 , Page(s): 435 - 436
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (316 KB) |  | HTML iconHTML  

    We report the realization of 140 nm emitter TPD/CuPc (N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine/copper phthalocyanine) with cutoff frequency fT = 300 kHz. Our devices were grown on high-resistivity p-type float-zone silicon collector and implemented with an aluminum grid base feature a high and stable current gain well above 400. The present transistors are the first metal-base transistors employing double hole injection layer to feature current gain without any sign of degradation. View full abstract»

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  • Electrical and Magnetic Properties of Higher Manganese Silicide Nanostructures

    Publication Year: 2012 , Page(s): 437 - 440
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (406 KB) |  | HTML iconHTML  

    Higher manganese silicide, Mn15Si26, nanostructures were grown using CVD using a coordination compound precursor. These nanostructures exhibit p-type semiconducting behavior. They also exhibit a nonzero magnetic moment even at room temperature and the magnetic transition temperature appears to be near 330 K. View full abstract»

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  • PolyMethyl Methacrylate Thin-Film-Based Field Emission Microscope

    Publication Year: 2012 , Page(s): 441 - 443
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (271 KB) |  | HTML iconHTML  

    A field emission microscope (FEM) is a useful tool for investigating molecular surface structures. Conventional FEMs suffer from poor image contrast level and low sensitivities when low-energy electron beams are applied. In this article, a new anode material is employed to improve the FEM imaging performance. We demonstrate that the device has the capability of clearly capturing images of facet boundaries of crystal structures at the tip of a zinc oxide (ZnO) nanowire as defect sites on a Polymethyl methacrylate (PMMA) film that is exposed to electron beams. The clear image of facet boundaries has not been reported in conventional FEM images. View full abstract»

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  • Fabrication of optical device arrays using patterned growth of ZnO nanostructures

    Publication Year: 2012 , Page(s): 444 - 447
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (443 KB) |  | HTML iconHTML  

    An on-site catalyst-free and seedless synthesis method is presented for patterned growth of ZnO nanostructures and easy integration into arrayed microdevices. The optoelectronic ZnO devices, exhibiting Schottky diode behavior, are highly sensitive to UV illumination. We demonstrate that the patterned synthesis method combined with conventional lithography provides a facile way of fabricating arrayed UV sensory or switch devices with large on/off ratio and rapid on/off response. View full abstract»

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  • Single Mesowire Transistor From Perylene Tetracarboxylic Diimide

    Publication Year: 2012 , Page(s): 448 - 450
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (461 KB) |  | HTML iconHTML  

    We have recently fabricated new nano/mesowires of perylene tetracarboxylic diimide (PTCDI) without side chains by self-assembling them from a gas phase. In this letter, we discuss a single PTCDI mesowire transistor that was successfully fabricated, characterized, and modeled. This organic n-channel field effect transistor shows good output and transfer characteristics. Our transistor model includes the Poole-Frenkel electric field dependence of charge carrier mobility in organic materials and fits all experimental output characteristics of the transistor. The zero-field charge carrier mobility of the PTCDI mesowire is found to be 0.72 cm2/(V·s). The experimental results are promising for the further development of single nanowire transistors and advancement of organic nanoelectronics. View full abstract»

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  • A Scalable Memory-Based Reconfigurable Computing Framework for Nanoscale Crossbar

    Publication Year: 2012 , Page(s): 451 - 462
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1309 KB) |  | HTML iconHTML  

    Nanoscale molecular electronic devices amenable to bottom-up self-assembly into a crossbar structure have emerged as a promising candidate for future electronic systems. To address some of the design challenges in molecular crossbar, we propose “memory-based architecture for reconfigurable computing” (MBARC), where memory, instead of switch-based logic functions, is used as the computing element. MBARC leverages on the fact that regular and periodic structures of molecular crossbar are attractive for a dense memory design. The main idea in MBARC is to partition a logic circuit, store the partitions as multi-input-multi-output lookup tables in a memory array, and then, use a simple CMOS-based scheduler to evaluate the partitions in a topological time-multiplexed manner. Compared to existing reconfigurable nanocomputing models, the proposed memory-based computing has three major advantages: 1) it minimizes the requirement of programmable interconnects (PIs); 2) it minimizes the number of CMOS interfacing elements that are required for level restoration and cascading logic blocks; and 3) it can achieve higher defect tolerance through efficient use of redundancy. Simulation results for a set of ISCAS benchmarks show average improvement of 32% in area, 21% in delay, and 34% in energy per vector compared to the implementation of a nanoscale field-programmable gate array. Effectiveness of the framework is also studied for two large sequential circuits, namely, 2-D discrete cosine transform and eight-tap finite-impulse-response filter. View full abstract»

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  • Theoretical Investigation of Traveling-Wave Amplification in Metallic Carbon Nanotubes Biased by a DC Field

    Publication Year: 2012 , Page(s): 463 - 471
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (570 KB) |  | HTML iconHTML  

    Traveling-wave amplification along a carbon nanotube (CNT) under dc-ac fields is theoretically investigated. The ac conductivity of a metallic CNT is found with respect to the applied dc bias. For this purpose, the Boltzmann transport equation (BTE) is solved within the relaxation time approximation (RTA) by separating the ac and dc distributions. The problem is solved both exactly and approximately by semianalytical and analytical means, respectively. It is shown that an absolute negative ac conductivity accompanies a negative differential conductivity beyond a threshold dc field of 3 × 105 V/m. The complex propagation factor of the allowed surface wave modes is found by coupling the BTE current with Maxwell's equations and solving a transcendental equation. The slow-wave factor and attenuation steadily increase with the dc field amplitude. Beyond the threshold field, amplification occurs, which is a promising result toward enabling traveling-wave amplifiers using CNTs. The amplification is shown to be a result of Bloch-type oscillations. View full abstract»

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  • Work Function Engineering With Linearly Graded Binary Metal Alloy Gate Electrode for Short-Channel SOI MOSFET

    Publication Year: 2012 , Page(s): 472 - 478
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (426 KB) |  | HTML iconHTML  

    Over the last few decades, silicon-on-insulator (SOI) technology has been identified as one possible solution for enhancing the performance of CMOS because of its numerous advantages over conventional bulk CMOS technology. One of the primary drawbacks of short-channel SOI MOSFET is the degradation of device threshold voltage with decreasing channel length. Drain-induced barrier-lowering (DIBL) effect, generated from high drain bias, is the main cause behind this length-dependent nature of threshold voltage. This “instability” in threshold voltage is responsible for making SOI device design very challenging. The instability that is known as the threshold voltage rolloff restricts further scaling of SOI devices. In this paper, an idea of work function engineering with continuous horizontal mole fraction variation in a binary alloy gate has been proposed and implemented theoretically. Analytical model-based simulation verified that performance of proposed SOI MOSFET is improved as it has higher immunity to DIBL effect. View full abstract»

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  • MOSFETs Made From GaN Nanowires With Fully Conformal Cylindrical Gates

    Publication Year: 2012 , Page(s): 479 - 482
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (396 KB) |  | HTML iconHTML  

    We report novel metal-oxide-semiconductor field effect transistors (MOSFETs) based on individual gallium nitride (GaN) nanowires with fully conformal cylindrical gates. The W/Al2O3 gates were deposited by atomic layer deposition. Reverse-bias breakdown voltages exceeded the largest gate voltage tested (-35 V). The nanowire MOSFETs showed complete pinchoff, with threshold voltages between -4 and -12 V. Maximum transconductances exceeded 10 μS, and ON/OFF current ratios higher than 10 8 were measured. Significant gating hysteresis and memory effects were also present, indicative of charge traps. Although further optimization is needed, these results represent a promising step forward in the development of efficient GaN nanowire-based FETs. View full abstract»

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  • MOS Devices With High-κ (ZrO _2 ) _x (La _2 O _3 ) _{1-x} Alloy as Gate Dielectric Formed by Depositing ZrO _2 /La _2 O _3 /ZrO _2 Laminate and Annealing

    Publication Year: 2012 , Page(s): 483 - 491
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    An amorphous (ZrO2)x(La2O3)1-x alloy formed by depositing a ZrO2/La2O3/ZrO2 laminate and a subsequent annealing was employed as the gate dielectric for metal-oxide-semiconductor (MOS) devices. The (ZrO2)x(La2O3)1-x alloy is found to have a high permittivity κ of 26.2 with negligible amount of bulk traps, both of which are very desirable for advanced gate dielectrics. By integrating the (ZrO2)x(La 2O3)1-x alloy with an SiON interfacial layer as the gate stack, it displays good frequency dispersion in capacitance-voltage (C -V) characteristics and low interfacial trap density of 1.52 × 1011 cm-2 eV-1. In addition, the current conduction mechanism of the gate stack is observed to be Fowler-Nordheim tunneling and the leakage current of 3.6 × 10-6 A/cm2 at the gate voltage of -1 V for equivalent oxide thickness of 1.1 nm can be achieved, which is superior to other high-κ dielectrics. Furthermore, satisfactory reliability is verified by bias temperature instability measurement. Most importantly, this gate stack not only exhibits a promising perspective for advanced CMOS technology but introduces a more reliable process to form an alloy-based high-κ gate dielectric. View full abstract»

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  • Quantum Transport and Current Distribution at Radio Frequency in Multiwall Carbon Nanotubes

    Publication Year: 2012 , Page(s): 492 - 500
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (746 KB) |  | HTML iconHTML  

    Multiwall carbon nanotubes represent a low-dimensional material that could serve as building blocks for future carbon-based nanoelectronics. The understanding of the electromagnetic performances at radio frequency of these materials for use in nanointerconnects is strictly related to the analysis of their transport properties as function of the working conditions. In this paper, we present an explicit expression of the conducting channels as function of diameter, temperature, doping, and supply voltage for both metallic and semiconducting carbon nanotubes. The proposed formula is based on the Dirac cone approximation of the conducting band energy of graphene nearby the Fermi points, combined with the Landauer-Buttiker formalism. Simplified expressions are also obtained in case of large diameter nanotubes. We show that the conductance, kinetic inductance, and quantum capacitance of each carbon shell are strongly affected by those parameters, and, consequently, that the current distribution among the shells of a multiwall carbon nanotube at radio frequency could be optimized with the proper definition of the nanotube configuration versus the working conditions. View full abstract»

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  • Performance Analysis of Si Nanowire Biosensor by Numerical Modeling for Charge Sensing

    Publication Year: 2012 , Page(s): 501 - 512
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1135 KB) |  | HTML iconHTML  

    A numerical study on the operation of Si nanowire (NW) biosensors in charge-based sensing is presented. The simulation is built on physical models that, upon numerical convergence, coherently account for Fermi-Dirac, Poisson-Boltzman, site-binding and Gouy-Chapman-Stern theories in self-consistent manner. The method enables us to disentangle the impact of key design and experimental setup factors and assess their contribution to the sensitivity, linearity, and stability of such sensors. Our results quantitatively show SiNW sensor is significantly more stable when biased through solution gate than back gate; dense functional group at oxide surface and good SAM coverage are essential to linear and sensitive detection of uniformly distributed targets; compared to high concentration target detection, the effect of NW surface-to-volume ratio (S/V ) plays a more profound role in biomolecule detection when targets are at very low concentration, in which case, optimal S/V exists for a maximum sensitivity. Arbitrary down scaling beyond such S/V point may have reverse effect on sensor sensitivity. View full abstract»

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  • Properties of Metal–Graphene Contacts

    Publication Year: 2012 , Page(s): 513 - 519
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (627 KB) |  | HTML iconHTML  

    We present a study on the metal-graphene contact properties. Utilizing a dual-gate field-effect transistor device, an energetic separation between the Fermi level and the Dirac point in the contact areas can be adjusted deliberately by applying an appropriate front-gate voltage that acts only on the channel. This front-gate voltage is compensated by an opposite large-area back-gate voltage, thereby mimicking the metal induced doping effect. A back-gate voltage sweep enables identifying two distinct resistance peaks-a result of the combined impact of the graphene cones in the contact and in the channel region. Comparing our experimental data with simulations allows extracting the coupling strength between metal and graphene and also estimating the magnitude of the metal-induced doping concentration in the case of palladium contacts. In contrast to conventional metal-semiconductor contacts, our simulations predict a decreased on-current for increased coupling strength in graphene field-effect transistors. View full abstract»

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  • A Flexible ZnO Nanowire-Based Humidity Sensor

    Publication Year: 2012 , Page(s): 520 - 525
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (779 KB) |  | HTML iconHTML  

    In this paper, the authors report the direct growth of ZnO nanowires (NWs) on a flexible substrate by the hydrothermal process and the fabrication of ZnO NW-based humidity sensor. It was found that average length and diameter of the ZnO NWs were 0.6 μm and 50 nm, respectively. It was also found that resistance of the ZnO NWs decreased by 45% as we increased the relative humidity from 52% to 90%. Furthermore, it was found that measured resistance was very stable with negligible fluctuation after 16 days continuous testing. View full abstract»

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  • Influence of Channel and Underlap Engineering on the High-Frequency and Switching Performance of CNTFETs

    Publication Year: 2012 , Page(s): 526 - 533
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (814 KB) |  | HTML iconHTML  

    We have comprehensively studied the influence of the channel and underlap engineering on the switching and high-frequency performance of carbon nanotube field-effect transistors (CNTFETs). Various source/drain and channel-engineered CNTFETs have been investigated and optimized architectures have been concluded from simulations. Performance parameters such as switching time τ and cutoff frequency fT as well as ambipolarity and on/off ratio Ion/ Ioff have been calculated and optimized. New CNTFETs with staircase doping in the underlap region (SU-CNTFETs)] have been proposed and the optimized underlap length and doping level have been concluded. Adding this kind of underlaps to conventional CNTFETs improves fT, τ, and Ion/I off and limits the leakage current simultaneously. For the first time, laterally asymmetric channel CNTFETs with a realistic staircase doping (SLAC-CNTFETs) have been proposed. It is shown that SLAC-CNTFET has an improved RF and switching performance while maintaining a good Ion /Ioff. The effect of single halo implantation on the aforementioned parameters has been calculated and it is revealed that it degrades the figures of merit. Detailed reasoning of the aforementioned characteristics has been discussed based on the gate and channel electric field distributions and the quantum capacitance. The impact of fringing field capacitances on fT has been computed and shown that it is not negligible. Finally, our calculations for an individual CNTFET with metallic contacts showed that the Schottky barriers at the contacts deteriorate almost all the figures of merits except Ioff. View full abstract»

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  • Tuning Electronic Structure of Graphene: A First-Principles Study

    Publication Year: 2012 , Page(s): 534 - 541
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (712 KB) |  | HTML iconHTML  

    Based on first-principles study, tuning of electronic structure of graphene is reported. The emergence of band gap in this semimetal can be accomplished through different mechanisms. In this study, we have reported on the band gap modulations in graphene through chemical functionalization with oxygen, under the application of external stress, and through the creation of vacancies. Our study suggests that all these mechanisms alter either electronic properties or both structural and electronic properties of graphene. As a result, these mechanisms completely destroy the nature of massless Dirac fermions of graphene. Also, we report on the effect of static electric field on the band gap in hydrogenated graphene (graphane). The combined action of structural modifications that involves stretching and compression of C-C bonds in the hexagonal network and charge transfer mechanism are responsible for the gap opening in electronic spectrum of graphene, which is essential for the future application of graphene in electronics. The introduction of strain is a nondestructive method when compared to other methods for band gap engineering in graphene. View full abstract»

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  • Orientation Modulated Epitaxy of Cu Nanorods on Si(1 0 0) Substrate

    Publication Year: 2012 , Page(s): 542 - 545
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    Epitaxial growth of Cu nanorod films on hydrogen-terminated Si(100) substrates by oblique angle deposition (OAD) was investigated. It is found out that the crystallographic orientation of Cu nanorod films exhibits a 45° in-plane rotation with respect to the substrate. When the incident angle of deposition was increased from normal to 80°, the distribution of Cu(111) poles is observed to spread out gradually, whereas the spread in poles is severe beyond 80°, indicating higher epitaxy quality for Cu deposited at lower incident angles. In addition, two sets of twin poles are induced at high-incident angles, while one set can be suppressed by altering flux direction 45° azimuthally about substrate normal. The mechanism of epitaxy development in the OAD grown Cu films is explained. View full abstract»

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  • PLGA Micro- and Nanoparticles Loaded Into Gelatin Scaffold for Controlled Drug Release

    Publication Year: 2012 , Page(s): 546 - 553
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (637 KB) |  | HTML iconHTML  

    Curcumin and bovine serum albumin (BSA) were used as model drugs and loaded into microand nanoparticles of biodegradable poly(lactic-co-glycolic acid) (PLGA). The PLGA was incorporated into hydrophilic and biocompatible gelatin scaffolds to design a controlled drug release system. The gelatin scaffolds were cross-linked using glutaraldehyde. The controlled delivery of drugs from biologically active PLGA microand nanoparticles was measured and these showed consistent release for 30 days. Curcuminand BSA-loaded PLGA micro/nanoparticles-based gelatin scaffolds define a novel approach to embed multiple drug molecules to overcome multidrug resistance as well as depict a new type of biocompatible and biodegradable implant. Such scaffold constructs can be used for breast implants after lumpectomy to not only overcome cosmetic issues, but also to provide sustained drug release during healing process. In one type of construct, only BSA-loaded microparticles were mixed with gelatin, while in the other type of construct, both BSAand curcumin-loaded PLGA microparticles were embedded. BSAand curcumin-loaded nanoparticles were also embedded into gelatin constructs to see the effects of particle size on drug release. After 30 days, cumulative BSA release from PLGA microand nanoparticles embedded in gelatin scaffold were measured to be 69.87% and 86.11%, respectively. The cumulative release of curcumin was measured to be 53.11% and 60.42% from curcumin-loaded PLGA microand nanoparticles, respectively. A statistically significant difference was seen in cumulative drug release from these scaffolds (p value <; 0.05). View full abstract»

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  • Transmission-Line Model for Multiwall Carbon Nanotubes With Intershell Tunneling

    Publication Year: 2012 , Page(s): 554 - 564
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (619 KB) |  | HTML iconHTML  

    The electromagnetic behavior of multiwall carbon nanotubes (MWCNTs), in the frequency range where only intraband transitions are allowed, depends on the combinations of different aspects: the number of effective conducting channels of each shell, the electron tunneling between adjacent shells, and the electromagnetic interaction between shells and the environment. This paper proposes a general transmission-line (TL) model for describing the propagation of electric signals along MWCNTs at microwave through terahertz frequencies that takes into account all these aspects. The dependence of the number of conducting channels of the single shell on the shell chirality and radius is described in the framework of the quasi-classical transport theory. The description of the intershell tunneling effects on the longitudinal transport of the π-electrons is carried on the basis of the density matrix formalism and Liouville's equation. The electromagnetic coupling between the shells and ground plane is described in the frame of the classical TL theory. The intershell tunneling qualitatively changes the form of the TL equations through the tunneling inductance and capacitance operators, which have to be added, respectively, in series to the (kinetic and magnetic) inductance matrix and in parallel to the (quantum and electrical) capacitance matrix. For carbon nanotube (CNT) lengths greater than 500 nm, the norm of the tunneling inductance operator is greater than 60% of the norm of the total inductance in the frequency range from gigahertz to terahertz. The tunneling inductance is responsible for a considerable coupling between the shells and gives rise to strong spatial dispersion. The model has been used to analyze the eigenmodes of a double-wall CNT above a ground plane. The intershell tunneling gives arise to strong anomalous dispersion in antisymmetrical modes. View full abstract»

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  • Electrical Properties of Silicon Nanowire Fabricated by Patterning and Oxidation Process

    Publication Year: 2012 , Page(s): 565 - 569
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (393 KB) |  | HTML iconHTML  

    We are reporting electrical properties of Si nanowire field-effect transistors with a Schottky barrier formed at the electrodes. The channel widths are varied using a top-down process of electron-beam patterning followed by surface oxidation from a few micrometers to the sub-10-nm level. The field-effect mobility increases gradually with decreasing channel width to 20 nm. On the other hand, the mobility decreases drastically when the channel width is smaller than 20 nm. The mobility enhancement is attributed to the stress build up during the oxidation of nanowire, while the drastic mobility degradation observed below a 20-nm linewidth is attributed to the surface scattering of electrons caused by the high surface/volume ratio of nanowire. The highest mobility value was obtained at a 20-nm linewidth with a value of ~1270 cm2/Vs. View full abstract»

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  • Joint Energy Harvesting and Communication Analysis for Perpetual Wireless Nanosensor Networks in the Terahertz Band

    Publication Year: 2012 , Page(s): 570 - 580
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (710 KB) |  | HTML iconHTML  

    Wireless nanosensor networks (WNSNs) consist of nanosized communicating devices, which can detect and measure new types of events at the nanoscale. WNSNs are the enabling technology for unique applications such as intrabody drug delivery systems or surveillance networks for chemical attack prevention. One of the major bottlenecks in WNSNs is posed by the very limited energy that can be stored in a nanosensor mote in contrast to the energy that is required by the device to communicate. Recently, novel energy harvesting mechanisms have been proposed to replenish the energy stored in nanodevices. With these mechanisms, WNSNs can overcome their energy bottleneck and even have infinite lifetime (perpetual WNSNs), provided that the energy harvesting and consumption processes are jointly designed. In this paper, an energy model for self-powered nanosensor motes is developed, which successfully captures the correlation between the energy harvesting and the energy consumption processes. The energy harvesting process is realized by means of a piezoelectric nanogenerator, for which a new circuital model is developed that can accurately reproduce existing experimental data. The energy consumption process is due to the communication among nanosensor motes in the terahertz band (0.1-10 THz). The proposed energy model captures the dynamic network behavior by means of a probabilistic analysis of the total network traffic and the multiuser interference. A mathematical framework is developed to obtain the probability distribution of the nanosensor mote energy and to investigate the end-to-end successful packet delivery probability, the end-to-end packet delay, and the achievable throughput of WNSNs. Nanosensor motes have not been built yet and, thus, the development of an analytical energy model is a fundamental step toward the design of WNSNs architectures and protocols. View full abstract»

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Aims & Scope

The IEEE Transactions on Nanotechnology is devoted to the publication of manuscripts of archival value in the general area of nanotechnology, which is rapidly emerging as one of the fastest growing and most promising new technological developments for the next generation and beyond.

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Meet Our Editors

Editor-in-Chief
Fabrizio Lombardi
Dept. of ECE
Northeastern Univ.