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Controlled Fabrication of Nanogaps in Ambient Environment for Molecular Electronics

D. R. Strachan·D. E. Smith·D. E. Johnston·T. -H. Park·M. J. Therien·D. A. Bonnell·A. T. Johnson
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Abstract

We have developed a controlled and highly reproducible method of making nanometer-spaced electrodes using electromigration in ambient lab conditions. This advance will make feasible single molecule measurements of macromolecules with tertiary and quaternary structures that do not survive the liquid-helium temperatures at which electromigration is typically performed. A second advance is that it yields gaps of desired tunnelling resistance, as opposed to the random formation at liquid-helium temperatures. Nanogap formation occurs through three regimes: First it evolves through a bulk-neck regime where electromigration is triggered at constant temperature, then to a few-atom regime characterized by conductance quantum plateaus and jumps, and finally to a tunnelling regime across the nanogap once the conductance falls below the conductance quantum.

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D. R. Strachan, D. E. Smith, D. E. Johnston, T. -H. Park, M. J. Therien, D. A. Bonnell, A. T. Johnson. 2005-04-05. Controlled Fabrication of Nanogaps in Ambient Environment for Molecular Electronics. https://doi.org/10.1063/1.1857095

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