Search results for "Nanoelectronics"
showing 10 items of 36 documents
Devices based on semiconductor nanowires
2009
Recently, nanoelectromechanical systems (NEMS) have attracted much attention due to their unique properties and possible applications that differ greatly from those of microelectromechanical systems. NEMS operating frequencies may achieve giga- and terahertz levels and their power consumption and heat capacity is extremely low. Moreover, integration levels may reach 1012 devices per cm−2. In this review, we present techniques for integrating semiconductor materials in NEMS. In particular, we examine fabrication, structure, properties and potential applications of two main classes of NEMS, namely, resonators and switches.
Effect of high-k materials in the control dielectric stack of nanocrystal memories
2004
In this paper we studied program/erase characteristics by FN tunneling in Si nanocrystal memories. Starting from a very good agreement between experimental data and simulations in the case of a memory cell with a thin tunnel oxide, Silicon dots as medium for charge storage, and a CVD silicon dioxide used as control dielectric, we present estimated values of the charge trapping when a high-k material is present in the control dielectric. We then show preliminary results of nanocrystal memories with control dielectric containing high-k materials. ©2004 IEEE.
Formation and Rupture of Schottky Nanocontacts on ZnO Nanocolumns
2007
In this paper, the electrical transport and mechanical properties of Pt/ZnO Schottky nanocontacts have been studied simultaneously during the formation and rupture of the nanocontacts. By combining multidimensional conducting scanning force spectroscopy with appropriated data processing, the physical relevant parameters (the ideality factor, the Schottky barrier height, and the rupture voltage) are obtained. It has been found that the transport curves strongly depend on the loading force. For loading forces higher than a threshold value, the transport characteristics are similar to those of large-area Schottky contact, while below this threshold deviations from strictly thermionic emission …
Independent Geometrical Control of Spin and Charge Resistances in Curved Spintronics
2019
Spintronic devices operating with pure spin currents represent a new paradigm in nanoelectronics, with higher energy efficiency and lower dissipation as compared to charge currents. This technology, however, will be viable only if the amount of spin current diffusing in a nanochannel can be tuned on demand while guaranteeing electrical compatibility with other device elements, to which it should be integrated in high-density three-dimensional architectures. Here, we address these two crucial milestones and demonstrate that pure spin currents can effectively propagate in metallic nanochannels with a three-dimensional curved geometry. Remarkably, the geometric design of the nanochannels can b…
Dielectrophoresis as an assembly method for carbon nanotube memory elements
2010
The experiments described in this Master's thesis aim to assess the practicality of using dielectrophoresis (DEP) for assembling memory elements from carbon nanotubes (CNTs). These elements were field-effect transistors (FETs) with a wide hysteresis window. The devices assessed were made on a silicon substrate with a HfO2 - TiO2 - HfO2 gate dielectric layer to ensure a predictable hysteresis for memory operation. The FETs were used for further research in regard to environmental effects in their operation. An average yield of 12.5 % over 26 different trapping attempts, a total of 650 gaps, was achieved for single trapped CNTs in a two-electrode configuration with a 1 µm gap between electrod…
Metal-nanoparticle-G4-DNA conjugates and their DC conductivity measurements
2013
Due to superior self-assembly properties, DNA is a very promising candidate for the basis of future bottom-up solutions for molecular electronics and therefore the conductivity of DNA is a very crucial question. In this work DC conductivity measurements on conjugates consisting of G-quadruplex DNA and metal nanoparticles were carried out. The fabrication and results obtained from the electrical measurements of three types of conjugates (20nm G4-AgNP chains, 20nm G4-AuNP flowers and 60nm G4-AuNPs) are reported. Additionally, 20nm AuNP chains coated with G4 were fabricated but not measured electrically. Results reported here indicate that in ambient conditions G4-DNA exhibits insulating behav…
Fabrication of Quasi-One-Dimensional Superconducting Micro- and Nanostructures
2007
Wires capable of conducting electric current are basic blocks of all electronic applications. Of particular interest for nanoelectronics are superconducting elements taking advantage of the superconductor's macroscopic quantum coherence and zero resistance. Recently there appeared indications that due to quantum fluctuations the dissipationless electric current (supercurrent) can be suppressed in ultra-narrow superconducting channels with the effective diameter below approximately 10 nm. In this Review we will describe methods of fabrication of quasi-one-dimensional superconducting micro- and nanowires suitable for electric transport measurements at cryogenic temperatures. In the first sect…
Defined-size DNA triple crossover construct for molecular electronics: modification, positioning and conductance properties.
2011
We present a novel, defined-size, small and rigid DNA template, a so-called B-A-B complex, based on DNA triple crossover motifs (TX tiles), which can be utilized in molecular scale patterning for nanoelectronics, plasmonics and sensing applications. The feasibility of the designed construct is demonstrated by functionalizing the TX tiles with one biotin-triethylene glycol (TEG) and efficiently decorating them with streptavidin, and furthermore by positioning and anchoring single thiol-modified B-A-B complexes to certain locations on a chip via dielectrophoretic trapping. Finally, we characterize the conductance properties of the non-functionalized construct, first by measuring DC conductivi…
Simulation of electromagnetic properties in carbon nanotubes and graphene-based nanostructures
2012
As carbon nanotubes (CNT) and graphene nanostructures (GNR) constitute the basis of high-speed nanoelectronics and nanosensors, we examine the fundamental properties of var- ious CNT-metal (Me), GNR-Me, and CNT-graphene interconnects. The cluster approach based on the multiple scattering theory as well as effective medium approximation were used to model the dispersion law, electronic density of states (DOS), and conductivity, etc. Multiple scattering problems were solved for nanostructures with radial (quantum dots) and axial (nanowires, nano- tubes) symmetry. Interconnect capacitances and impedances have been evaluated in the GHz and THz regimes. Parametrical numerical simulations of cond…
Direct Surface Relief Formation in Polymer Films
2013
Due to active development of nanoelectronics, the studies of methods of nanorelief surface formation in different materials, in particular polymers are very important. Organic polymer films in consequence of their dielectric and optical properties have been used as basis of these devices. In this paper, the possibility of UV optical record and electron beam lithography in different type of polymeric films was studied. Mechanisms of molecular structure changes: photoisomerization, destruction, cross-linking and oxidation have been discussed. The results of UV illumination of polyurethanes, polyacrylates, and some block-copolymers were described. The element analysis of polybutadiene block co…