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‘Soft’ Au, Pt and Cu contacts for molecular junctions through surface-diffusion-mediated deposition

Nature Nanotechnology volume 5, pages 612–617 (2010)Cite this article

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Abstract

Virtually all types of molecular electronic devices depend on electronically addressing a molecule or molecular layer through the formation of a metallic contact. The introduction of molecular devices into integrated circuits will probably depend on the formation of contacts using a vapour deposition technique, but this approach frequently results in the metal atoms penetrating or damaging the molecular layer. Here, we report a method of forming ‘soft’ metallic contacts on molecular layers through surface-diffusion-mediated deposition, in which the metal atoms are deposited remotely and then diffuse onto the molecular layer, thus eliminating the problems of penetration and damage. Molecular junctions fabricated by this method exhibit excellent yield (typically >90%) and reproducibility, and allow examination of the effects of molecular-layer structure, thickness and contact work function.

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Figure 1: Schematic of the SDMD process.
Figure 2: Cross-section of a PPF/NAB/Au junction.
Figure 3: J–V measurements for different deposition techniques.
Figure 4: J–V measurements for SDMD junctions with various molecular layers and top contacts.
Figure 5: J–V measurements for diaminoalkane monolayer junctions.

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Acknowledgements

The authors acknowledge financial support from the National Sciences and Research Council of Canada, the Alberta Ingenuity Fund, the University of Alberta, and the National Institute for Nanotechnology (NINT). We acknowledge P. Li for FIB-TEM analysis, K. Harris and H. Yan for scientific discussions, and B. Szeto for technical assistance.

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Authors and Affiliations

  1. Department of Materials, Science and Engineering, The Ohio State University, 2041 College Road, Columbus, Ohio, 43210, USA

    Andrew P. Bonifas

  2. National Institute for Nanotechnology, National Research Council of Canada, T6G 2G2, Edmonton, Alberta, Canada

    Andrew P. Bonifas & Richard L. McCreery

  3. Department of Chemistry, University of Alberta, T6G 2R3, Edmonton, Alberta, Canada

    Richard L. McCreery

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Contributions

A.B. and R.M. conceived and designed the experiments, A.B. performed the experiments, A.B. and R.M. co-wrote the manuscript and Supplementary Information.

Corresponding author

Correspondence to Richard L. McCreery.

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The authors declare no competing financial interests.

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Bonifas, A., McCreery, R. ‘Soft’ Au, Pt and Cu contacts for molecular junctions through surface-diffusion-mediated deposition. Nature Nanotech 5, 612–617 (2010). https://doi.org/10.1038/nnano.2010.115

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