Open Access Nano Express

Carbon-fiber tips for scanning probe microscopes and molecular electronics experiments

Gabino Rubio-Bollinger1*, Andres Castellanos-Gomez1,2*, Stefan Bilan3, Linda A Zotti3, Carlos R Arroyo1,2, Nicolás Agraït1,4 and Juan C Cuevas3

Author Affiliations

1 Departamento de Física de la Materia Condensada (C–III), Universidad Autónoma de Madrid, Campus de Cantoblanco, Madrid, E-28049, Spain

2 Kavli Institute of Nanoscience, 5046 Delft University of Technology, Delft, 2600, GA, Netherlands

3 Departamento de Física Teórica de la Materia Condensada (C–III), Universidad Autónoma de Madrid, Campus de Cantoblanco, Madrid, E-28049, Spain

4 Instituto Madrileño de Estudios Avanzados en Nanociencia IMDEA-Nanociencia, Madrid, E-28049, Spain

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Nanoscale Research Letters 2012, 7:254 doi:10.1186/1556-276X-7-254

Published: 15 May 2012

Abstract

We fabricate and characterize carbon-fiber tips for their use in combined scanning tunneling and force microscopy based on piezoelectric quartz tuning fork force sensors. An electrochemical fabrication procedure to etch the tips is used to yield reproducible sub-100-nm apex. We also study electron transport through single-molecule junctions formed by a single octanethiol molecule bonded by the thiol anchoring group to a gold electrode and linked to a carbon tip by the methyl group. We observe the presence of conductance plateaus during the stretching of the molecular bridge, which is the signature of the formation of a molecular junction.

Keywords:
Single-molecule junction; Carbon electrodes; Carbon electronics; STM break junction; Carbon tip; Quartz tuning fork.; PACS; 07.79.-v, scanning probe microscopes and components; 68.37.Ef, scanning tunneling microscopy (including chemistry induced with STM); 73.63.-b, electronic transport in nanoscale materials and structures; 85.65. + h, molecular electronic devices; 73.40.-c, electronic transport in interface structures; PACS; 07.79.-v, scanning probe microscopes and components; 68.37.Ef, scanning tunneling microscopy (including chemistry induced with STM); 73.63.-b, electronic transport in nanoscale materials and structures; 85.65. + h, molecular electronic devices; 73.40.-c, electronic transport in interface structures