Single-Walled Carbon Nanotube Based Molecular Switch Tunnel Junctions

• Published in: Chemphyschem Vol. 4; no. 12; pp. 1335 - 1339
• Main Authors: Diehl, Michael R., Steuerman, David W., Tseng, Hsian-Rong, Vignon, Scott A., Star, Alexander, Celestre, Paul C., Stoddart, J. Fraser, Heath, James R.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 15.12.2003; WILEY‐VCH Verlag; Wiley
• Subjects: Applied sciences; catenanes; Electronics; Exact sciences and technology; molecular electronics; Molecular electronics, nanoelectronics; nanotubes; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; solid-state devices; supramolecular chemistry; tetrathiafulvalene; Voltage current curve; Material selection; Electrode material; catenanes; solid-state devices; Nanoelectronics; tetrathiafulvalene; nanotubes; Molecular electronics; Singlewalled nanotube; Self organization; Catenane; Tunnel junction; Selector switch; supramolecular chemistry
• ISSN: 1439-4235; 1439-7641
• DOI: 10.1002/cphc.200300871

This article describes two‐terminal molecular switch tunnel junctions (MSTJs) which incorporate a semiconducting, single‐walled carbon nanotube (SWNT) as the bottom electrode. The nanotube interacts noncovalently with a monolayer of bistable, nondegenerate [2]catenane tetracations, self‐organized by their supporting amphiphilic dimyristoylphosphatidyl anions which shield the mechanically switchable tetracations from a two‐micrometer wide metallic top electrode. The resulting 0.002 μm2 area tunnel junction addresses a nanometer wide row of ≈2000 molecules. Active and remnant current–voltage measurements demonstrated that these devices can be reconfigurably switched and repeatedly cycled between high and low current states under ambient conditions. Control compounds, including a degenerate [2]catenane, were explored in support of the mechanical origin of the switching signature. These SWNT‐based MSTJs operate like previously reported silicon‐based MSTJs, but differently from similar devices incorporating bottom metal electrodes. The relevance of these results with respect to the choice of electrode materials for molecular electronics devices is discussed. Using a redox‐switchable [2]catenane (see picture) as an approximately one‐nanometer‐cubic molecular switch, two‐terminal molecular switch tunnel junctions (MSTJs), which incorporate a semiconducting single‐walled carbon nanotube (SWNT) as the bottom electrode and a two‐micrometer wide metallic top electrode, have been fabricated. Active and remnant current‐voltage measurements demonstrated that these devices can be reconfigurably switched and repeatedly cycled between high and low current states under ambient conditions.