Showing papers on "Nanoelectronics published in 1998"
TL;DR: In this paper, the authors discuss some of the methods to characterize the structure of nanoparticles using electron microscopy and discuss some exciting novel applications of nanarticles in nanoelectronics and nanophotonics, and show that nanoparticles play an important role in producing atmospheric pollutants.
Abstract: Small metal and semiconductor particles with a size of a few nanometers are one of the important systems in modern materials science. Nanoparticles have found applications in many fields, ranging from catalysis to magnetic storage. In the present work, we discuss some of the methods to characterize the structure of nanoparticles using electron microscopy. We also discuss some of the exciting novel applications of nanoparticles in nanoelectronics and nanophotonics. Finally, we show that nanoparticles play an important role in producing atmospheric pollutants.
28 citations
01 Apr 1998-Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms
TL;DR: In this paper, the authors proposed an in-plane-gate (IPG) transistor, which is completely maskless and does not require any alignment procedures since gate, source and drain are all written in the same writing process.
Abstract: In directly writing the 30 nm focus of a focussed Ga-ion beam (FIB) with an energy of 100 keV we define insulating lines in two-dimensional electronic layers in semiconductors. Ga ions act in GaAs and silicon as deep impurities or p-type doping, respectively. In this way the insulation by such written lines is due to lateral depletion within npn-like interfaces. In writing two FIB lines with a close spacing we define conducting channels between them. In applying a voltage of several Volts to the adjacent areas of the channel relative to it we can tune the effective width of the channel in the range of a few 100 nm to zero and obtain thus a one-dimensional field-effect-transistor-type structure. This transistor exhibits a pure lateral field effect and is thus topologically very different to current transistor concepts. Due to its particular geometry it is called in-plane-gate (IPG) transistor, since the gate and the channel are in the same plane. The fabrication of this type of transistor is thus completely maskless and does not require any alignment procedures since gate, source and drain are all written in the same writing process. Due to the computer-control of the beam deflection even more complex structures are just a question of software and do not need a set of specific masks or photoresist like in the classical lithography. The required line ion dose is of the order of 106 cm−1 which means that there are about 100 ions per μm implanted. For devices with maximum micron dimensions only a few hundred ions need thus to be implanted. With typical beam currents of up to 30 pA there are 2 × 108 ions available in a second and it is thus realistic to assume that millions of devices can be written per second with the focused ion beam. In this way the sequential character of the FIB implantation does not limit the fabrication speed severely due to the low required ion doses. Room temperature as well as low temperature operation of this device are presented and discussed in the framework of applications in nanoelectronics. The very low capacitance between the IPG and the channel is discussed. Especially the specularity of ballistic electrons at such an IPG is investigated. In changing the gate voltage and its sign, this specularity can be varied by 20%. It is related to electron transport in undisturbed or ion-implanted regions which leads to velocity-modulated systems.
17 citations
01 Jan 1998
TL;DR: Functional integration, that is the possibility of exploiting quantum effects to obtain a function specific behavior, is illustrated as design technique by compact memory cells and logic families with reduced circuit complexity.
Abstract: This paper analyzes the impact of nano-scale technology on future circuit design and describes several prototypes of logic and memory applications. Resonant tunneling transistors, single electron transistors, and quantum cellular automata are reviewed as relevant nanoelectronic device categories. In regard to the limited interconnectivity and the sensitivity of the devices to parameter variations we discuss bit level systolic arrays, a propagate instruction array processor, and fault tolerant logic. Furthermore, functional integration, that is the possibility of exploiting quantum effects to obtain a function specific behavior, is illustrated as design technique by compact memory cells and logic families with reduced circuit complexity.
15 citations
01 Jan 1998
TL;DR: Carbon nanotubes (CNTs) are shown to offer great opportunities in nanoelectronic devices and NEMS because of their inherent nanoscale sizes, intrinsic electric conductivities, and seamless hexagonal network architectures.
Abstract: Carbon nanotubes (CNTs) are shown to promise great opportunities in nanoelectronic devices and nanoelectromechanical systems (NEMS) because of their inherent nanoscale sizes, intrinsic electric conductivities, and seamless hexagonal network architectures. I present our collaborative work with Stanford on exploring CNTs for nanodevices in this talk. The electrical property measurements suggest that metallic tubes are quantum wires. Furthermore, two and three terminal CNT junctions have been observed experimentally. We have proposed and studied CNT-based molecular switches and logic devices for future digital electronics. We also have studied CNTs based NEMS inclusing gears, cantilevers, and scanning probe microscopy tips. We investigate both chemistry and physics based aspects of the CNT NEMS. Our results suggest that CNT have ideal stiffness, vibrational frequencies, Q-factors, geometry-dependent electric conductivities, and the highest chemical and mechanical stabilities for the NEMS. The use of CNT SPM tips for nanolithography is presented for demonstration of the advantages of the CNT NEMS.
7 citations
Posted Content•
TL;DR: Based on the understanding that chemical bonds can act as tunnel junctions in the Coulomb blockade regime, and on the technical ability to coat a DNA strand with metal, the authors suggest that DNA can be used to built logical devices.
Abstract: Based on the understanding that chemical bonds can act as tunnel junctions in the Coulomb blockade regime, and on the technical ability to coat a DNA strand with metal, we suggest that DNA can be used to built logical devices. We discuss two explicit examples: a Single Electron Tunneling Transistor (SET) and a Quantum Bit Element. These devices would be literally in the nano-meter scale and would be able to operate at room temperature. In addition they would be identical to each other, highly stable and would have a self assembly property.
3 citations
TL;DR: Some models of macromolecular electronic systems, first steps in their creation and difficulties on the way of their design and synthesis were examined in this article, where the first steps of their creation were described.
Abstract: Some models of macromolecular electronic systems, first steps in their creation and difficulties on the way of their design and synthesis were examined.
3 citations
12 Mar 1998
TL;DR: In this paper, the present status and key issues of research on the compound semiconductor quantum nanoelectronics, introducing recent results obtained by author's group at Research Center for Interface Quantum Electronics (RCIQE) as specific examples.
Abstract: Recent progress of the "nanofabrication" technology has opened up exciting possibilities of constructing novel quantum nanoelectronics directly based on the quantum mechanics where wave-particle motions of individual electrons are controlled by artificial quantum structures such as quantum wells, quantum wires, quantum dots and single and multiple tunneling barriers so as to realize devices with new functions and higher performances. This paper discusses the present status and key issues of research on the compound semiconductor quantum nanoelectronics, introducing recent results obtained by author's group at Research Center for Interface Quantum Electronics (RCIQE) as specific examples. Since electrons manifest predominantly either wave-nature or particle-nature depending on their environments, one can conceptually envisage two kinds of nanoelectronics in the quantum regime, i.e., "quantum wave electronics" and "single electronics". A particular emphasis is paid here on single electronics because of its promising prospects. Main topics include prospects, expected roles and nano-fabrication issues of compound semiconductor single electron devices as well as key issues on compound semiconductor quantum wave devices.
2 citations
TL;DR: In this article, a simple adiabatic transport model was used to show that basic electronic functions can theoretically be achieved by manipulating a single propagating mode in a system with quantized levels of conduction.
Abstract: Using a simple adiabatic transport model, we show that basic electronic functions may theoretically be achieved by manipulating a single propagating mode in a system with quantized levels of conduction. For a quantum point contact with a centered and tunable depletion island formed in a two-dimensional electron gas, a sinusoidal island bias results in a pulsed source–drain conductance. For single, multiple parallel, and multiple independent configurations of this device, the functions of a digital clock, digital frequency doubler, and hexadecimal counter are described.