1. Department of Physics, Haifa 32000, Israel
2. Department of Chemistry, Haifa 32000, Israel
3. Solid State Institute, Technion-Israel Institute of Technology, Haifa 32000, Israel

Correspondence to: Erez Braun¹ Correspondence should be addressed to E.B. (Email: erez@physics.technion.ac.il).

Abstract

Recent research in the field of nanometre-scale electronics has focused on two fundamental issues: the operating principles of small-scale devices, and schemes that lead to their realization and eventual integration into useful circuits. Experimental studies on molecular¹ to submicrometre² quantum dots and on the electrical transport in carbon nanotubes^{3, 4, 5} have confirmed theoretical predictions^{6, 7, 8} of an increasing role for charging effects as the device size diminishes. Nevertheless, the construction of nanometre-scale circuits from such devices remains problematic, largely owing to the difficulties of achieving inter-element wiring and electrical interfacing to macroscopic electrodes. The use of molecular recognition processes and the self-assembly of molecules into supramolecular structures⁹,¹⁰ might help overcome these difficulties. In this context, DNA has the appropriate molecular-recognition¹¹ and mechanical^{12, 13, 14, 15, 16} properties, but poor electrical characteristics prevent its direct use in electrical circuits. Here we describe a two-step procedure that may allow the application of DNA to the construction of functional circuits. In our scheme, hybridization of the DNA molecule with surface-bound oligonucleotides is first used to stretch it between two gold electrodes; the DNA molecule is then used as a template for the vectorial growth of a 12 m long, 100 nm wide conductive silver wire. The experiment confirms that the recognition capabilities of DNA can be exploited for the targeted attachment of functional wires.