Silicon nanowires grown in place

Researchers from the Oregon Health and Science University and Sharp Laboratories of America have found a way to grow nanowires between pairs of metal electrodes deposited on silicon wafers.

The process is a step toward a new way to make smaller, faster electronics components.

The researchers used an electric field to direct the growth of silicon nanowires between specific electrodes, and used electrodes that have sharp points to ensure that the nanowires and electrodes are in good contact with each other.

The researchers found that they could grow thinner diameter nanowires at lower temperatures, and they could vary the density of the nanowires by changing the pressure at which they were grown. The researchers were able to produce uniform nanowires with diameters of 17 nanometers, which is 5,000 times narrower than a human hair.

The method could someday be used to fabricate millions of silicon nanowire devices like transistors in place on a chip.

The researchers are now testing the electrical properties of the nanowires. Several challenges must be met to make the process practical, including making practical contacts, finding the best composition for the nanowires, and handling the effects of surface impurities, according to the researchers.

In a similar demonstration in 2002, Stanford University researchers showed that it was possible to grow carbon nanotubes between electrodes. The nanowire work appeared in the February 23, 2004 issue of Applied Physics Letters.