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Highly conductive nanolayers on strontium titanate produced by preferential ion-beam etching

Nature Materials volume 4, pages 593596 (2005) | Download Citation

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Abstract

Developing fabrication methods for electronically active nanostructures is an important challenge of modern science and technology. Fabrication efforts1,2,3,4 for crystalline materials have been focused on state-of-the-art epitaxial growth techniques. These techniques are based on deposition of precisely controlled combinations of various materials on a heated substrate. We report a method that does not require deposition and transforms a nanoscale layer of a complex crystalline compound into a new material using low-energy ion-beam preferential etching (IBPE). We demonstrate this method by transforming a widely used5,6,7,8,9,10 insulator model system, SrTiO3, into a transparent conductor. Most significantly, the resistivity decreases with decreasing temperature as T2.5±0.3 and eventually falls below that of room-temperature copper. These transport measurements imply a crystal quality in the conduction channel comparable to that obtained1 with the highest-quality growth techniques. The universality of low-energy IBPE implies wide potential applicability to fabrication of other nanolayers.

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Acknowledgements

The authors would like to thank J. B. Chlistunoff, I. Campbell, T. Kimura and X. Gao for their help. This work was supported by the US Department of Energy.

Author information

Affiliations

  1. Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

    • David W. Reagor
  2. Brookhaven National Laboratory, Upton, New York 11973, USA

    • Vladimir Y. Butko

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Competing interests

The authors declare no competing financial interests.

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Correspondence to David W. Reagor.

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DOI

https://doi.org/10.1038/nmat1402

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