Current–voltage characteristics of an LB monolayer of didecylammonium tricyanoquinodimethanide measured between macroscopic gold electrodes

Abstract

(2002) 'Currentvoltage characteristics of an LB monolayer of didecylammonium tricyanoquinodimethanide measured between macroscopic gold electrodes.', Journal of materials chemistry., 12 (10). pp. 3167-3171. Further information on publisher's website:http://dx.doi.org/10.1039/b203789kPublisher's copyright statement:Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. monolayer onto a gold surface. Using the "cold-gold" evaporation technique, a set of several macroscopic gold electrode pads were evaporated atop the LB monolayer. Pads which had macroscopic defects were electrical short circuits, but across many pads finite electrical currents were observed as a function of applied bias; however, no obvious electrical rectification was found. The monolayer thickness on a gold substrate measured by XPS to be ~22 Å. Reflection-absorption infrared spectroscopy (RAIRS) indicates that the molecules have a preferred orientation in the film, but are not well ordered. Angleresolved X-ray photoelectron spectroscopy (XPS) suggests that many of the molecules 2 are oriented anti-parallel to each other, possibly because dipole-dipole forces favor such an anti-parallel orientation. This latter observation helps to explain why no electrical rectification was found.

Electrical conduction through single molecules and self-assembled monolayers

“…The evaporated Au atoms from the boat will release most energy in collisions with the Ar atoms, before they land on the cooled substrate. Since the technique relies on scattered Au atoms to land on the side of the substrate facing away from the boat, the deposited thickness was reported to be only 17 nm for every 600 nm recorded by the quartz crystal monitor; the latter is directly in line with the evaporation boat [164]. Another method to fabricate molecular junctions on the micrometer scale with a vapor-deposited top contact, is by simply making a very large amount of devices [36].…”

The study of charge transport through organic thin films: mechanism, tools and applications

“…The evaporation of the second electrode without damaging the fragile molecular layer and inducing electrical shorts between the two electrodes still presents a challenge. In an attempt to circumvent this problem, a number of different strategies such as lift-off float-on Au pads (Xu et al 2002) or deposition of cold gold (Xu et al 2002) have been employed successfully. Although these approaches have produced laboratory test structures, they are difficult to scale up for the fabrication of circuits or molecular devices because they are highly specialized and time consuming.…”

Ultrathin π‐Conjugated Polymer Films for Simple Fabrication of Large‐Area Molecular Junctions

“…[21] The fabrication of the second electrode on top of SAMs without damaging the fragile molecular layer and inducing electrical shorts between the two electrodes still represents a challenge. In an attempt to overcome this problem a number of different strategies, such as lift-off float-on Au pads [22] or deposition of cold gold [23] have been successfully employed. Although these approaches have produced laboratory test structures, it is difficult for them to be scaled up for the fabrication of circuits or molecular devices, because they are highly specialized and time consuming.…”