Gold Nano Anchors Put Nanowires In Their Place

ScienceDaily (Nov. 17, 2004) — Researchers at the National Institute of Standards and Technology (NIST) have demonstrated a technique for growing well-formed, single-crystal nanowires in place---and in a predictable orientation---on a commercially important substrate.

See Also:

Matter & Energy

Reference

The method uses nanoparticles of gold arranged in rows on a sapphire surface as starting points for growing horizontal semiconductor "wires" only 3 nanometers (nm) in diameter. Other methods produce semiconductor nanowires more than 10 nm in diameter. NIST chemists' work was highlighted in the Oct. 11 issue of Applied Physics Letters.*

Part of the vision of nanotechnology is the possibility of building powerful, extraordinarily compact sensors and other devices out of atomic-scale components. So-called "nanowires"---long thin crystals of, e.g., a semiconductor--- could not only link nanoelectronic devices like conventional wire but also function as devices themselves, tipped with photodetector or light-emitting elements, for example.

An obvious stumbling block is the problem of working with components so small that only the most sophisticated measurement instruments can even track them. To date, the most successful nanowire alignment method involved growing large numbers of the rod-like crystals on a suitable base like blades of grass, shearing them off, mixing them in a solvent, and forcing them to align by either flow or surface confinement on the test substrate to orient most of the crystals in a specific horizontal direction. Further photolithography steps are required to ensure that nanowires are positioned correctly.

In contrast, the NIST technique grows arrays of nanowires made of zinc oxide, a semiconductor widely used in optoelectronics, with precise alignments. The gold "anchors" are placed with a chemical etching step and the orientation of the wires--horizontal, vertical or at a 60 degree angle from the surface--is determined by tweaking the size of the gold particles.

###

*B. Nikoobakht, C.A. Michaels, S.J. Stranick, M. Vaudin, Applied Physics Letters, Oct. 11, 2004, Vol. 85, Issue 15, pp. 3244-3246.

Recommend this story on Facebook, Twitter,
and Google +1:

Other bookmarking and sharing tools:

| More

Story Source:

The above story is reprinted from materials provided by National Institute Of Standards And Technology.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.