Cuniberti / Fagas / Richter Introducing Molecular Electronics

1. Auflage 2006
ISBN: 978-3-540-31514-8
Verlag: Springer
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 680, 537 Seiten, eBook

Reihe: Lecture Notes in Physics

Klaus von Klitzing Max-Planck-Institut fur ¨ Festk¨ orperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany Already many Cassandras have prematurely announced the end of the silicon roadmap and yet, conventional semiconductor-based transistors have been continuously shrinking at a pace which has brought us to nowadays cheap and powerful microelectronics. However it is clear that the traditional scaling laws cannot be applied if unwanted tunnel phenomena or ballistic transport dominate the device properties. It is generally expected, that a combination of silicon CMOS devices with molecular structure will dominate the ?eld of nanoelectronics in 20 years. The visionary ideas of atomic- or molecular-scale electronics already date back thirty years but only recently advanced nanotechnology, including e.g. scanning tunneling methods and mechanically controllable break junctions, have enabled to make distinct progress in this direction. On the level of f- damentalresearch,stateofthearttechniquesallowtomanipulate,imageand probechargetransportthroughuni-molecularsystemsinanincreasinglyc- trolled way. Hence, molecular electronics is reaching a stage of trustable and reproducible experiments. This has lead to a variety of physical and chemical phenomena recently observed for charge currents owing through molecular junctions, posing new challenges to theory. As a result a still increasing n- ber of open questions determines the future agenda in this ?eld.

Zielgruppe

Research

Autoren/Hrsg.

Cuniberti, Gianaurelio

Fagas, Giorgos

Richter, Klaus

Inhaltsverzeichnis

Theory.- Foundations of Molecular Electronics – Charge Transport in Molecular Conduction Junctions.- AC-Driven Transport Through Molecular Wires.- Electronic Structure Calculations for Nanomolecular Systems.- Ab-initio Non-Equilibrium Green’s Function Formalism for Calculating Electron Transport in Molecular Devices.- Tight-Binding DFT for Molecular Electronics (gDFTB).- Current-Induced Effects in Nanoscale Conductors.- Single Electron Tunneling in Small Molecules.- Transport through Intrinsic Quantum Dots in Interacting Carbon Nanotubes.- Introducing Molecular Electronics: A Brief Overview.- Introducing Molecular Electronics: A Brief Overview.- Experiment.- Contacting Individual Molecules Using Mechanically Controllable Break Junctions.- Intrinsic Electronic Conduction Mechanisms in Self-Assembled Monolayers.- Making Contacts to Single Molecules: Are We There Yet?.- Six Unimolecular Rectifiers and What Lies Ahead.- Quantum Transport in Carbon Nanotubes.- Carbon Nanotube Electronics and Optoelectronics.- Charge Transport in DNA-based Devices.- Outlook.- CMOL: Devices, Circuits, and Architectures.- Architectures and Simulations for Nanoprocessor Systems Integrated on the Molecular Scale.

Leseproben

CMOL: Devices, Circuits, and Architectures (p. 447-448)

Konstantin K. Likharev and Dmitri B. Strukov
Stony Brook University, Stony Brook, NY 11794, USA

Abstract. This chapter is a brief review of the recent work on various aspects of the prospective hybrid semiconductor/nanowire/molecular ("CMOL") integrated circuits. The basic idea of such circuits is to combine the advantages of the currently dominating CMOS technology (including its flexibility and high fabrication yield) with those of molecular devices with nanometer-scale footprint. Two-terminal molecular devices would be self-assembled on a pre-fabricated nanowire crossbar fabric, enabling very high function density at acceptable fabrication costs. Preliminary estimates show that the density of active devices in CMOL circuits may be as high as 1012 cm-2 and that they may provide an unparalleled information processing performance, up to 1020 operations per cm2 per second, at manageable power consumption. However, CMOL technology imposes substantial requirements (most importantly, that of high defect tolerance) on circuit architectures. In the view of these restrictions, the most straightforward application of CMOL circuits is terabitscale memories, in which powerful bad-bit-exclusion and error-correction techniques may be used to boost the defect tolerance.

The implementation of Boolean logic circuits is more problematic, though our preliminary results for reconfigurable, uniform FPGA-like CMOL circuits look very encouraging. Finally, CMOL technology seems to be uniquely suitable for the implementation of the "CrossNet" family of neuromorphic networks for advanced information processing including, at least, pattern recognition and classification, and quite possibly much more intelligent tasks. We believe that these application prospects justify a large-scale research and development effort focused on the main challenge of the field, the high-yield self-assembly of molecular devices.


1 Introduction

The recent spectacular advances in molecular electronics (for reviews see, e.g., 1–3 and other chapters of this collection), and especially the experimental demonstration of molecular single-electron transistor by several groups [4–8] give hope for the practical introduction, within the next 10 to 20 years, of the first integrated circuits with active single- or few-molecule devices. This long-expected breakthrough could not have arrived more timely. Indeed, the recent results [9,10] indicate that the current VLSI paradigm, based on a combination of lithographic patterning, CMOS circuits, and Boolean logic, can hardly be extended into a-few-nm region. The main reason is that at gate length below 10 nm, the sensitivity of parameters (most importantly, the gate voltage threshold) of silicon field-effect transistors (MOSFETs) to inevitable fabrication spreads grows exponentially. As a result, the gate length should be controlled with a few-angstrom accuracy, far beyond even the longterm projections of the semiconductor industry [11]. Even if such accuracy could be technically implemented using sophisticated patterning technologies, this would send the fabrication facilities costs (growing exponentially even now) skyrocketing, and lead to the end of Moore’s Law some time during the next decade.