By Topic

Nanotechnology, IEEE Transactions on

Issue 2 • Date March 2007

Filter Results

Displaying Results 1 - 25 of 25
  • Table of contents

    Page(s): C1
    Save to Project icon | Request Permissions | PDF file iconPDF (38 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Nanotechnology publication information

    Page(s): C2
    Save to Project icon | Request Permissions | PDF file iconPDF (36 KB)  
    Freely Available from IEEE
  • Modeling Crosstalk Effects in CNT Bus Architectures

    Page(s): 133 - 145
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1198 KB) |  | HTML iconHTML  

    Carbon nanotubes (CNTs) have been widely proposed as interconnect fabric for nano and very deep submicron (silicon-based) technologies due to their robustness to electromigration. In this paper, issues associated with crosstalk among bus lines implemented by CNTs are investigated in detail. CNT-based interconnects are modeled and the effects of crosstalk on performance and correct operation are evaluated by simulation. Existing models are modified to account for geometries in bus architectures made of parallel single-walled nanotubes and a single multiwalled nanotube. New RLC equivalent circuits are proposed for these bus architectures. A novel bus architecture with low crosstalk features is also proposed. This bus architecture is made of dual-walled nanotubes arranged in parallel. In this architecture, the crosstalk-induced delay and corresponding uncertainty (as well as crosstalk-induced peak voltage) are significantly reduced; a modest area penalty is incurred. Reductions up to 59% for the crosstalk-induced delay and up to 81% for the crosstalk-induced peak voltage are reported. These results confirm that the proposed bus arrangement noticeably improves performance and provides reliable operation View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Novel Hybrid Voltage Controlled Ring Oscillators Using Single Electron and MOS Transistors

    Page(s): 146 - 157
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (827 KB) |  | HTML iconHTML  

    This paper proposes two kinds of novel hybrid voltage controlled ring oscillators (VCO) using a single electron transistor (SET) and metal-oxide-semiconductor (MOS) transistor. The novel SET/MOS hybrid VCO circuits possess the merits of both the SET circuit and the MOS circuit. The novel VCO circuits have several advantages: wide frequency tuning range, low power dissipation, and large load capability. We use the SPICE compact macro model to describe the SET and simulate the performances of the SET/MOS hybrid VCO circuits by HSPICE simulator. Simulation results demonstrate that the hybrid circuits can operate well as a VCO at room temperature. The oscillation frequency of the VCO circuits could be as high as 1 GHz, with a -71 dBc/Hz phase noise at 1 MHz offset frequency. The power dissipations are lower than 2 uW. We studied the effect of fabrication tolerance, background charge, and operating temperature on the performances of the circuits View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis of the Voltage Swing for Logic and Memory Applications in Si/SiGe Resonant Interband Tunnel Diodes Grown by Molecular Beam Epitaxy

    Page(s): 158 - 163
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (953 KB) |  | HTML iconHTML  

    A method is investigated to directly engineer the voltage swing in SiGe resonant interband tunnel diodes (RITDs). Voltage swing, defined here as the voltage difference between the peak voltage and the projected peak voltage, is independent of series resistance, and thus directly impacts the noise margin in hybrid tunnel diode memory and logic applications. The three components of the total RITD current are analyzed to describe the voltage swing. The dependence of voltage swing on delta-doping concentrations and post-growth annealing temperatures in SiGe RITDs grown by low-temperature molecular beam epitaxy (LT-MBE) is investigated and the experimental results are compared with a theoretical analysis. Techniques to increase the voltage swing are discussed View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Design and Evaluation of Magnetic Fields for Nanoparticle Drug Targeting in Cancer

    Page(s): 164 - 170
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1763 KB) |  | HTML iconHTML  

    The retention of superparamagnetic nanoparticles under the influence of a high-gradient magnetic field was investigated. A simulation algorithm for prediction of the particle's trajectories and, therefore, the total amount of adhered particles in an artificial vessel was developed. Comparisons between in vitro experiments and simulations showed that the required experimental magnetic moments were greater than the theoretically estimated magnetic moments. This paper presents a method for investigating magnetic fields and for determining the magnetic moment of particles by simulation of their trajectories. The detailed function of magnetic drug targeting is of great importance in animal studies and in human therapies View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Light-Driven Hybrid Bioreactor Based on Protein-Incorporated Polymer Vesicles

    Page(s): 171 - 176
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (556 KB) |  | HTML iconHTML  

    In vitro biochemical synthesis is regarded as a major challenge in replicating cellular functions in engineered systems. Presented is a nanosized hybrid factory where photo-induced biochemical reactions take place resulting in the production of biomolecules. For this purpose, we reconstructed in vitro proton-powered ATP synthesis using artificial organelles, BR/F0F1-ATP synthase reconstituted polymer vesicles (proteopolymersomes), which have been made without organic solvent. Importantly, BR/F0F1-ATP synthase incorporated polymer vesicles showed an excellent proton leakage characteristic under modified conditions. This research is expected to enhance the potential applications of synthetic artificial membranes from in vitro investigation of cellular metabolism to the fabrication of light-driven biomolecular electronic devices such as optical memory and biofuel cell View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Coarsening of the Nanolamellar Structure in a Soft Magnetic Alloy

    Page(s): 177 - 185
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (9888 KB) |  | HTML iconHTML  

    Crystallization from a cobalt base Co65Si15B 14Fe4Ni2 amorphous magnetic alloy yielded an interesting highly modulated nanolamellar structure with lamellar spacing of about 5 nm. Coarsening of this structure was investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), convergent beam electron diffraction (CBED), and X-ray electron dispersive spectrum (XEDS) techniques and was found to initiate at grain boundaries, which provided nucleation sites for equilibrium phases. Rod-shaped Co2B precipitates were observed along the nanolamellae; such precipitates also played a role in coarsening. A coarse lamellar structure subsequently developed which eventually broke up into equiaxed grains. A metastable Co3Si phase was also observed to form by an allotropic transformation. The coarsening of the nanolamellar structure was found to occur largely by discontinuous coarsening processes. The crystallographic relationship between the equilibrium and metastable phases was determined View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance Metrics of a 5 nm, Planar, Top Gate, Carbon Nanotube on Insulator (COI) Transistor

    Page(s): 186 - 190
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (349 KB) |  | HTML iconHTML  

    The performance of a planar, 5 nm top gate, carbon nanotube on insulator (COI) field-effect transistor (COIFET) with source/drain underlaps is analyzed. The performance metrics of switching delay time and cutoff frequency are calculated. A 2 nm thick, relatively low-K, SiO 2 gate dielectric combined with a source/drain underlap geometry and insulating substrate minimizes the parasitic gate to source CGS and gate to drain CGD capacitances and results in a 23 fs switching delay time. The simplicity of the device design is required to satisfy the constraints of a self-assembly process. The device analyzed is also a scaled version of recently demonstrated CNTFETs on sapphire View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Realization of Nonvolatile Memory Devices Using Small Organic Molecules and Polymer

    Page(s): 191 - 195
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (653 KB) |  | HTML iconHTML  

    Intensive research is currently underway to exploit the highly interesting properties of nano-sized particles and organic molecules, for applications in the optical and electronic sectors. Recently, it has been shown that nano-sized particles and small molecules can be used in polymer matrices to realize memory devices. Such memory devices are simple to fabricate, relying typically on the spin on technique. In this work, an attempt is made to utilize small organic molecules embedded in an organic polymer, in the making of the presented memory devices. The ever elusive charging mechanism in such configurations, is also discussed View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Selective Solid-Phase Silicon Epitaxy of p+ Aluminum-Doped Contacts for Nanoscale Devices

    Page(s): 196 - 200
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1726 KB) |  | HTML iconHTML  

    A solid-phase epitaxy (SPE) process based on material inversion of an amorphous silicon (alpha-Si) on aluminum layer-stack is applied to form ultrashallow p-type junctions. In this paper, we demonstrate the controllability of the whole process when the junction area is reduced to the sub-100-nm range and the processing temperature is reduced to 400 degC. The SPE-Si to Si-substrate interface, analyzed locally by transmission electron microscopy and more systematically by the fabrication and electrical characterization of p+-n diodes, was found to be practically defect-free. Moreover, it is demonstrated by capacitance-voltage profiling that the Al-dopants do not diffuse into the bulk silicon for the used processing temperatures and the SPE p+-island to n-substrate transition is ideally abrupt. The I-V characteristics of the as-fabricated p+-n diodes are near ideal (n=1.03) and low-ohmic contact resistance to p- and p + regions is reliably obtained View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Four-Terminal FinFETs Fabricated Using an Etch-Back Gate Separation

    Page(s): 201 - 205
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1765 KB) |  | HTML iconHTML  

    A novel resist etch-back process for fabrication of separated-gate four-terminal FinFETs has been investigates. This process enabled co-fabrication of three-terminal (3T) and four-terminal (4T) FinFETs on a same chip. The fabricated 3T-FinFET shows excellent sub-threshold characteristics and drain induced barrier lowering (DIBL) value whereas the 4T-FinFET provides efficient Vth controllability. The effective Vth controllability with keeping a small sub-threshold slope has been confirmed in the synchronized double gate (DD) operation mode View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-Performance Poly-Si Nanowire NMOS Transistors

    Page(s): 206 - 212
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1239 KB) |  | HTML iconHTML  

    A novel field-effect transistor with Si nanowire (NW) channels is developed and characterized. To enhance the film crystallinity, metal-induced lateral crystallization (MILC) and/or rapid thermal annealing (RTA) techniques are adopted in the fabrication. In the implementation of MILC process, it is shown that the arrangement of seeding window plays an important role in affecting the resulting film structure. In this regard, asymmetric window arrangement, i.e., with the window locating on only one of the two channel sides is preferred. When MILC and RTA techniques are combined, it is found that single-crystal-like NWs are achieved, leading to significant performance improvement as compared with the control with channels made up of fine-grain structures by the conventional solid-phase crystallized (SPC) approach. Field-effect mobility up to 550 cm2/V-s is recorded in this study View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electrical Characterization of Ordered Si:P Dopant Arrays

    Page(s): 213 - 217
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1261 KB) |  | HTML iconHTML  

    We report on the ability to fabricate arrays of planar, nanoscale, highly doped phosphorus dots in silicon separated by source and drain electrodes using scanning tunneling microscope lithography. We correlate ex situ electrical measurements with scanning tunneling microscope (STM) images of these devices and show that ohmic conduction can be achieved through the disordered array with a P coverage of 0.8times1014 cm-2. In comparison, we show that an ordered array of P dots ~6 nm in diameter and containing ~50 P atoms separated by ~4 nm shows nonlinear I-V, characteristic of a series of metallic dots separated by tunnel barriers. These results highlight the use of STM lithography to pattern ordered dopants in silicon down to the sub-10 nm scale View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • 3-D Design and Analysis of Functional NEMS-gate MOSFETs and SETs

    Page(s): 218 - 224
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (937 KB) |  | HTML iconHTML  

    Nanoelectromechanical system (NEMS)-gate metal- oxide-semiconductor field effect transistor (MOSFET) and single- electron transistor (SET) structures are investigated by combining 3-D design and SPICE simulation. First, the metal gate is simulated by using a 3-D simulator, which enables to design realistic 3-D device structures, and its movement is studied for different design parameters. It is demonstrated that a low stiffness design of the structure is essential for a low-voltage actuation. Results are compared with theoretical numerical simulation and a tunable capacitor model is then embedded in a SPICE simulator and coupled either with a transistor model for MOS-NEMS or with a newly developed SET analytical model for SET-NEMS. It is shown that the use of NEMS membrane can add new functionalities to conventional MOSFET and SET, such as very abrupt switching of the current, which can break theoretical limits of MOSFET, or modulation of Coulomb oscillations governing SET characteristics View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Impact of Structure Relaxation on the Ultimate Performance of a Small Diameter, n-Type 〈110 〉 Si-Nanowire MOSFET

    Page(s): 225 - 229
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (747 KB) |  | HTML iconHTML  

    We investigate the impact of structure relaxation on the upper performance of a silicon nanowire metal-oxide-semiconductor field-effect-transistor (MOSFET) with small diameter employing a semiclassical transport model to calculate its ballistic I-V characteristics. For wires along the lang110rang axis and 1 nm diameter, structure relaxation induces large changes in the bond length of silicon atoms at the surface (~33%). Despite these bond length variations, the effect of reconstruction on the ballistic ON-current of Si-NW MOSFETs turns out negligible in the case considered, which can be attributed to an only slight variation of the electron effective mass after reconstruction View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Quantum Simulation of Device Characteristics of Silicon Nanowire FETs

    Page(s): 230 - 237
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (667 KB) |  | HTML iconHTML  

    A quantum simulation of silicon nanowire field-effect transistors has been performed in the frame work of the effective mass theory, where the three-dimensional Poisson equation was solved self-consistently with the mode-space nonequilibrium Green's function equations in the ballistic transport regime. The dependence of the device performance on the gate length and width for three types of gate configuration has been studied, focusing on the contribution of the tunneling current to the total current. The effects of gate underlap and the corner rounding of silicon body on the device performance have been also investigated quantitatively, leading to the conclusions that the gate underlap is an important factor in improving the subthreshold characteristics of the device, but the corner rounding of silicon body is not a significant factor, especially for devices with silicon body width of a few nanometers View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Real-Space Multigrid Method for Linear-Response Quantum Transport in Molecular Electronic Devices

    Page(s): 238 - 244
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (494 KB) |  | HTML iconHTML  

    We present a self-consistent ab initio simulation method to calculate coherent quantum transport through a molecule connected to metal electrodes in the linear-response regime. Density-functional theory (DFT) is applied to the metal-molecule-metal system. The molecule and the metal electrodes are treated on the same footing as one extended molecule. The Full Approximation Scheme (FAS) nonlinear multigrid technique is used to accelerate convergence in a nonorthogonal localized orbital basis. The Landauer formula is employed to calculate the current with the transmission function obtained from a Green's function calculation. The current-voltage characteristics of a benzene-1,4-dithiolate (BDT) extended molecule are studied as an example, and our results are compared to other theoretical calculations. We also show that a recently formulated constrained-current formalism is invariant to a reversal in the imposed current. Hence, the predicted voltage drop must be zero. This suggests the theory must be modified to properly treat possible nonlinearities in the nonzero current case View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Compositional Redistribution in Coherent Si1-xGex Islands on Si(100)

    Page(s): 245 - 249
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1377 KB)

    Coherent Si1-xGex island growth by molecular beam epitaxy is studied for a fixed growth temperature but for different Ge concentrations in the range 0.37 lesxles 0.56. A combined transmission electron microscopy, X-ray diffraction, and Raman spectroscopy characterization of the samples showed that during growth the Ge migrates towards the center of the large islands to minimize the strain energy, while maintaining epitaxial growth, and that the most uniform structures are obtained at higher Ge composition when the built-in strain is also higher View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Engineering Exchange Coupling in Double Elliptic Quantum Dots

    Page(s): 250 - 255
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (920 KB) |  | HTML iconHTML  

    Coupled elliptic quantum dots with different aspect ratios containing up to two electrons are studied using a model confinement potential in the presence of magnetic fields. Single and two-particle Schrodinger equations are solved using numerical exact diagonalization to obtain the exchange energy and chemical potentials. As the ratio between the confinement strengths in directions perpendicular and parallel to the coupling direction of the double dots increases, the exchange energy at zero magnetic field increases, while the magnetic field of the singlet-triplet transition decreases. By investigating the charge stability diagram, we find interdot quantum mechanical coupling increases with the dot aspect ratio, whereas the electrostatic coupling between the two dots remains nearly constant. With increasing interdot detuning, the absolute value of the exchange energy increases superlinearly followed by saturation. This behavior is attributed to the electron density differences between the singlet and triplet states in the asymmetric QD systems View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Precise Alignment of Single Nanowires and Fabrication of Nanoelectromechanical Switch and Other Test Structures

    Page(s): 256 - 262
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1584 KB) |  | HTML iconHTML  

    The integration of nanowires and nanotubes into electrical test structures to investigate their nanoelectronic transport properties is a significant challenge. Here, we present a single nanowire manipulation system to precisely maneuver and align individual nanowires. We show that a single nanowire can be picked up and transferred to a predefined location by electrostatic force. Compatible fabrication processes have been developed to simultaneously pattern multiple aligned nanowires by using one level of photolithography. In addition, we have fabricated and characterized representative devices and test structures including nanoelectromechanical switches with large on/off current ratios, bottom-gated silicon nanowire field-effect transistors, and both transfer-length-method and Kelvin test structures View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Put your technology leadership in writing [advertisement]

    Page(s): 263
    Save to Project icon | Request Permissions | PDF file iconPDF (370 KB)  
    Freely Available from IEEE
  • Order form for reprints

    Page(s): 264
    Save to Project icon | Request Permissions | PDF file iconPDF (345 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Nanotechnology Information for authors

    Page(s): C3
    Save to Project icon | Request Permissions | PDF file iconPDF (32 KB)  
    Freely Available from IEEE
  • Blank page [back cover]

    Page(s): C4
    Save to Project icon | Request Permissions | PDF file iconPDF (2 KB)  
    Freely Available from IEEE

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.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Kang L. Wang
University of California, Los Angeles
420 Westwood Plaza
Rm 66-147C, Engineering IV
Los Angeles, CA  90095-1594  90095-1594  USA
eic@tnano.org