By Topic

Nanotechnology, IEEE Transactions on

Issue 1 • Date Mar 2003

Filter Results

Displaying Results 1 - 10 of 10
  • Reliability scaling issues for nanoscale devices

    Page(s): 33 - 38
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (269 KB)  

    We discuss two specific scaling issues that can result in qualitative changes in device reliability prediction for nanoscale devices. The first of these involves a rapid increase in early failures due to a distribution of activation energies of defect precursors. We show that the slopes of the failure functions for hot carrier interface state generation (HCI) and time-dependent dielectric breakdown (TDDB) have simple physical interpretations in terms of a geometrical factor and the activation energy distribution width. The second issue involves a transition from single to multiple electrons causing individual defects. This picture allows simple physical explanations for the larger HCI damage in NMOS versus PMOS, the anomalous isotope effect of activation energies for HCI in the lucky electron model, and the observed power law dependence of the time to breakdown versus voltage for TDDB for ultrathin oxides. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pyrolysis temperature and time dependence of electrical conductivity evolution for electrostatically generated carbon nanofibers

    Page(s): 39 - 43
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (985 KB)  

    Carbon nanofibers were produced from polyacrylonitrile/N, N-Dimethyl Formamide (PAN/DMF) precursor solution using electrospinning and vacuum pyrolysis at temperatures from 773-1273 K for 0.5, 2, and 5 h, respectively. Their conductance was determined from I-V curves. The length and cross-section area of the nanofibers were evaluated using optical microscope and scanning probe microscopes, respectively, and were used for their electrical conductivity calculation. It was found that the conductivity increases sharply with the pyrolysis temperature, and increases considerably with pyrolysis time at the lower pyrolysis temperatures of 873, 973, and 1073 K, but varies, less obviously, with pyrolysis time at the higher pyrolysis temperatures of 1173 and 1273 K. This dependence was attributed to the thermally activated transformation of disordered to graphitic carbon. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optical study on II-VI semiconductor nanoparticles in Langmuir-Blodgett films

    Page(s): 44 - 49
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (461 KB)  

    Cadmium sulfide (CdS) nanoparticles formed within Langmuir-Blodgett (LB) films of stearic acid and calix[8]arene were studied with different optical methods including surface plasmon resonance (SPR), ellipsometry and UV-visible absorption and fluorescence spectroscopies. For the first time, the process of formation of CdS nanoparticles within LB films was monitored in-situ with SPR. The results of ellipsometry, SPR and UV-vis absorption spectroscopy were analyzed to evaluate simultaneously the thickness, refractive index and extinction coefficient of LB films. It was shown that all three parameters increase as a result of formation of CdS nanoparticles. Photoluminescence measurements provided direct confirmation directly for previous observation with UV-vis absorption spectroscopy of the blue spectral shift caused by CdS particles formation. The observed large Stoke's shift of the luminescence band is discussed in terms of the formation of "dark excitons" in the platelet-type CdS nanoclusters. AFM study shows the formation of pseudo-two dimensional platelets of CdS with the lateral dimensions in the range of 20-30 nm. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Selective MOCVD growth of ZnO nanotips

    Page(s): 50 - 54
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (754 KB) |  | HTML iconHTML  

    ZnO is a wide bandgap semiconductor with a direct bandgap of 3.32eV at room temperature. It is a candidate material for ultraviolet LED and laser. ZnO has an exciton binding energy of 60 meV, much higher than that of GaN. It is found to be significantly more radiation hard than Si, GaAs, and GaN, which is critical against wearing out during field emission. Furthermore, ZnO can also be made as transparent and highly conductive, or piezoelectric. ZnO nanotips can be grown at relatively low temperatures, giving ZnO a unique advantage over the other nanostructures of wide bandgap semiconductors, such as GaN and SiC. In the present work, we report the selective growth of ZnO nanotips on various substrates using metalorganic chemical vapor deposition. ZnO nanotips grown on various substrates are single crystalline, n-type conductive and show good optical properties. The average size of the base of the nanotips is 40 nm. The room temperature photoluminescence peak is very intense and sharp with a full-width-half-maximum of 120 meV. These nanotips have potential applications in field emission devices, near-field microscopy, and UV photonics. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Array-based architecture for FET-based, nanoscale electronics

    Page(s): 23 - 32
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1723 KB) |  | HTML iconHTML  

    Advances in our basic scientific understanding at the molecular and atomic level place us on the verge of engineering designer structures with key features at the single nanometer scale. This offers us the opportunity to design computing systems at what may be the ultimate limits on device size. At this scale, we are faced with new challenges and a new cost structure which motivates different computing architectures than we found efficient and appropriate in conventional very large scale integration (VLSI). We sketch a basic architecture for nanoscale electronics based on carbon nanotubes, silicon nanowires, and nano-scale FETs. This architecture can provide universal logic functionality with all logic and signal restoration operating at the nanoscale. The key properties of this architecture are its minimalism, defect tolerance, and compatibility with emerging bottom-up nanoscale fabrication techniques. The architecture further supports micro-to-nanoscale interfacing for communication with conventional integrated circuits and bootstrap loading. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effective boundary conditions for carriers in ultrathin SOI channels

    Page(s): 59 - 63
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (435 KB) |  | HTML iconHTML  

    We have studied electron backscattering from heavily doped source/drain extensions using both the solution of Boltzmann equation and Monte Carlo simulation, for a simple case of monochromatic incident "beam" of ballistic electrons. For the case of elastic scattering, numerical results for the total reflection coefficient R may be well described by a simple expression which has a clear physical sense within the Landauer formalism of mesoscopic transport. The reduction of R due to inelastic scattering was also analyzed using Monte Carlo simulation. We believe that our work paves a way toward simple and accurate modeling of nanoscale MOSFETs with thin electrode extensions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Enhanced radiative efficiency in GaN quantum dots grown by molecular beam epitaxy

    Page(s): 10 - 14
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (343 KB) |  | HTML iconHTML  

    Self-assembled GaN quantum dots (QDs), grown on AlN by molecular beam epitaxy, were investigated by time-resolved photoluminescence spectroscopy. We investigate the emission mechanism in GaN QDs by comparing the carrier recombination dynamics in single and multiple period QDs. At 100 K, the PL decay time in single period QD structures is considerably shorter than in stacked QDs. Compared to single period QDs, the room temperature PL efficiency is considerably enhanced in 20 period QDs due to the reduction in nonradiative recombination processes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A majority-logic device using an irreversible single-electron box

    Page(s): 15 - 22
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (552 KB) |  | HTML iconHTML  

    We describe a majority-logic gate device suitable for use in developing single-electron integrated circuits. The device consists of a capacitor array for input summation and an irreversible single-electron box for threshold operation. It accepts three binary inputs and produces a corresponding output, a complementary majority-logic output, by using the change in its tunneling threshold caused by the input signals; it produces a logical 1 output if two or three of the inputs are logical 0 and a logical 0 output if two or three of the inputs are logical 1. We combined several of these gate devices to form subsystems, a shift register and a full adder, and confirmed their operation by computer simulation. The gate device is simple in structure and powerful in terms of implementing digital functions with a small number of devices. These superior features will enable the device to contribute to the development of single-electron integrated circuits. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Novel single-electron logic circuits using charge-induced signal transmission (CIST) structures

    Page(s): 1 - 9
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (898 KB)  

    In this paper, on the basis of the Monte Carlo simulation, we demonstrate a method to realize logical operations by the use of the single-electron charge-induced signal transmission (CIST) circuit which we have proposed previously. First, we propose three new-type signal transmission circuits. Then, we demonstrate through construction of a NAND circuit and a full-adder circuit on the basis of the Monte Carlo simulation that we can construct any logic circuit by the use of these circuits. Since the CIST circuit can perform any logical operation and can transmit the state of the presence or absence of an electron and a hole as a binary signal over long distance during one clock cycle bidirectionally, these CIST circuits are expected to be applied to integrated circuit devices as a new circuit construction method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An RF circuit model for carbon nanotubes

    Page(s): 55 - 58
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (246 KB) |  | HTML iconHTML  

    We develop an RF circuit model for single walled carbon nanotubes for both dc and capacitively contacted geometries. By modeling the nanotube as a nanotransmission line with distributed kinetic and magnetic inductance as well as distributed quantum and electrostatic capacitance, we calculate the complex, frequency dependent impedance for a variety of measurement geometries. Exciting voltage waves on the nanotransmission line is equivalent to directly exciting the yet-to-be observed one dimensional plasmons, the low energy excitation of a Luttinger liquid. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

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