Researchers publish a detailed review of electrical contacts in one and two dimensional nanomaterials

February 16, 2012

( -- Researchers from the NIST Center for Nanoscale Science and Technology and Sandia National Laboratories have published a detailed review of recent experimental and theoretical work highlighting the unusual physics and material science of electrical contacts to nanostructures.

In the Nature Nanotechnology article, the researchers explain that existing models of electrical contacts in bulk are inapplicable at the nanoscale, and argue that in order for to progress to practical use, it is critical to control charge at the electrical contacts.

New models are required to understand contact formation and charge transport. In conventional contacts, the interface between a metal and a semiconductor is planar, but nanocontacts have multiple possible geometries, each with unique properties. The kinetics and thermodynamics of metal/nanostructure interfaces also differ from those of the bulk due to their small lateral dimensions and to the greater ability of nanostructures to accommodate strain. Three examples illustrate the range of contacts that are possible with different nanomaterials.

First, abrupt epitaxial silicide/silicon nanowire junctions with novel orientations can be formed at temperatures well below those required for thin metal films, providing new opportunities for emerging devices such as metal source-drain MOSFETs and SpinFETs.

Second, for metal contacts to carbon nanotubes, catalytically driven carbonization of the interface results in an electrically transparent graphene-CNT contact.

Finally, making low resistance ohmic contacts to semiconductor has proven challenging and requires new understanding of doping at the nanometer scale.

The researchers conclude that better understanding of the basic science of nanoscale contacts is necessary to allow to be incorporated into useful new device designs.

Explore further: Nanotubes find niche in electric switches

More information: Electrical contacts to one- and two-dimensional nanomaterials, F. Leonard and A. A. Talin, Nature Nanotechnology 6, 773-783 (2011).

Related Stories

Nanotubes find niche in electric switches

March 10, 2009

New research from Rice University and the University of Oulu in Oulu, Finland, finds that carbon nanotubes could significantly improve the performance of electrical commutators that are common in electric motors and generators.

Self-cooling observed in graphene electronics

April 3, 2011

With the first observation of thermoelectric effects at graphene contacts, University of Illinois researchers found that graphene transistors have a nanoscale cooling effect that reduces their temperature.

Recommended for you

Touchless displays superseding touchscreens?

October 2, 2015

While touchscreens are practical, touchless displays would be even more so. That's because, despite touchscreens having enabled the smartphone's advance into our lives and being essential for us to be able to use cash dispensers ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.