Nanotech excitement
New technique packs computing power on a microscopic wire

By Robert Sanders, Public Affairs

14 February 2002 | Imagine a chemical-sensing electronic device, complete with lasers and light-emitting diodes, on a wire less than a hundredth the width of a human hair.

This high-tech gadget, and others like it, is not the stuff of science fiction, say campus scientists, but is coming to the market in the very near future, thanks to a new electronics manufacturing technique developed in Berkeley labs.

The researchers have found a way to mate different materials along the length of a single nanowire that incorporates transistor junctions, light-emitting diodes and even lasers.

The development takes electronics from the two-dimensional world of today’s chips into the one-dimensional world of nanowires.

“This is a major advancement in the field of one-dimensional nano-structure research. The impact could be tremendous,” predicts Peidong Yang, assistant professor of chemistry and a faculty scientist in the Materials Science Division at Lawrence Berkeley National Lab.

Yang and graduate students Yiying Wu and Rong Fan report their results in the February issue of the peer-reviewed journal Nano Letters, a publication of the American Chemical Society.

The issue reports similar work by a Swedish team. The two groups independently made lattices that they say will make it possible to construct nanowires with otherwise incompatible materials. Such mixed bundles are essential to making electronics and other devices on an increasingly smaller scale. The nanowire devices, they say, could soon be manufactured cheaply using little more than a mixture of gases deposited on a foundation material.

“Because you can mix these materials, one wire could be a device itself as opposed to needing multiple wires to make a device,” said Larry Bock, president and CEO of Nanosys, Inc., a Palo Alto-based company that Yang co-founded.

Whereas today “you could cross two different wires…and create a device like a light-emitting diode,” he said, with nanowire technology “you could do all this on one wire.”

Bock predicts a nanowire device will be on the market within three to four years.

Nanotechnologists have long sought such a means to bring together materials on the nanoscopic scale that otherwise would be structurally incompatible. Much like conventional builders, nanoengineers mix a mélange of elements in hopes of creating entirely new classes that could revolutionize everything from energy production to manufacturing. In the field of electronics and optics, nanotechnology should lead to devices too small to see with the naked eye, but equal to or better than today’s hand-size electronics.

These research findings promise to make nanowire production both rapid and economical. In just one hour, millions of nanowires can be made at minimal expense.