Purdue facility to link scientists, entrepreneurs

In an effort to make electronic products that cost
less and deliver more, researchers at Indiana’s Purdue
University have found a way to coax molecules to grow
into microelectronic circuit elements.

BY JON VAN
Chicago Tribune

The approach, which scientists say is akin to the way
genes direct the growth of living tissue, places Purdue
among the leaders in a race to devise ways to grow
ultratiny integrated circuits, molecule by molecule.

Many believe that this approach – or something similar – will
be vital if the microelectronics industry is to continue
packing more elements onto a smaller space.

Today’s integrated circuits are fabricated on silicon and produced by a process that uses chemistry and light in a fashion similar to
how photographs are produced in a darkroom. But the technology has space limitations that will likely be reached by the end of this
decade. Hence, there is a rush among scientists and academic institutions to create new technologies for integrated circuits.

Purdue is one of several universities around the country building a center to foster research in nanotechnology, a science based on
manipulating materials on an atomic or molecular scale.

The Birck Nanotechnology Center is named for Michael Birck, co-founder of Naperville, Ill.-based Tellabs Inc., a telecommunications
equipment-maker. Birck and his wife, Katherine, donated $30 million to the center.

When the new facility opens in a few years, Purdue will have state-of-the-art nanofabrication equipment that will enable
researchers to make quicker advances in designing and characterizing new materials, said Hicham Fenniri, who is leading Purdue’s
integrated circuit research.

Special centers for nanotech research are needed not only for the advanced equipment needed to work at the molecular level, but
also to bring together chemists, engineers, biologists, physicists and other scholars who traditionally haven’t collaborated.

Chad Mirkin, a chemistry professor at Northwestern University, heads a new nanotech center in Evanston, Ill., and is a proponent of
building such centers as quickly as possible.

Nanotechnology research is producing useful results that can be commercialized to begin a new industry, as well as basic findings
about science, Mirkin said. The Midwest as a region needs to be at the forefront of what will become tomorrow’s new high-tech job
engine.

"It’s early," Mirkin said, "but it’s good to get in now. This is a sprint. If you don’t win the first couple of legs, you won’t be around to
finish the marathon. It’s just like building a high-tech company – if you move at a slow pace, you won’t be around with the heavy
hitters in a few years."

Discoveries in nanotechnology come at a time when universities have become much more oriented toward commercializing faculty
research.

James Cooper, a professor of electrical and computer engineering, said that Purdue is seeking to expand the traditional academic
paths to career success and include entrepreneurial activities along with research, teaching and publishing in academic journals.

"We constantly have companies come in to look at what’s going on here," said Cooper. "We’re trying to work with existing
companies and get start-ups going as well. The (university) president has made it clear that a goal here is to have an impact on the
economy."

Led by Fenniri, the Purdue researchers have studied how DNA works to construct living cells and have borrowed a few tricks.
Most notably, Fenniri said, some DNA molecules are attracted to water and others are repelled by it.

By attaching these water-loving and water-hating particles to synthetic molecules made of carbon, nitrogen, hydrogen and oxygen,
the scientists cause the molecules to assemble themselves as tubes. These molecular structures – called nanotubes – have
chemical "hooks" attached to their surfaces, so that other molecules can be hung on like ornaments on a Christmas tree.

This system enables Fenniri to program the tubes to conduct electrons, manipulate light or do other tasks typically required of
microcircuitry.

Because the water-hating elements are inside the tube and the water-loving components are on the outside, the structure is very
stable when placed in water, Fenniri said, and it even gains stability when heated.

"This opposes common wisdom," he said, "because generally when you heat something, it falls apart. Our demonstrations show
that these structures become more stable under the influence of temperature and attain a new level of self-organization."

Making molecules assemble themselves into a tiny cylinder is also an idea suggested by nature.

Nanotubes made entirely of carbon can be created naturally and have been fashioned by researchers at IBM Corp. into molecular
logic circuits. Discovered in the last decade, carbon nanotubes are a hot research area.

"A carbon nanotube is about 100 times stronger than steel," said Fenniri.

But there are problems in producing carbon nanotubes with desirable electronic properties and a high level of purity, he said. Also,
carbon nanotubes have limited versatility as a circuit material.

So Fenniri and his colleagues set out to construct nanotubes that contained carbon and other elements – molecular cylinders
designed to manipulate electrons and photons as needed. Their success in finding ways to make molecules assemble themselves
into predetermined structures has convinced Fenniri that he’s at the threshold of a new era in nanotechnology.

Northwestern’s Mirkin said that much nanotech research – including Fenniri’s – concerns building new microelectronics devices, but
progress in that area will be slow. The problem of getting millions or billions of tiny devices to self-assemble and wire up with one
another cannot be underestimated, he said.

"In nanotech, you have to be careful about overselling the electronics side of it, even though that’s what’s driven a lot of interest in
this research," Mirkin said. "Nanotech is going to impact so many areas, but electronics will be one of the last ones because it is so
hard."

At Purdue, Fenniri said that his group is leaving to others the problem of integrating nano-size electronic elements, and he noted that
his techniques for building nanotubes will have applications beyond electronics. One example might be ultrathin fiber made from
nanotubes that would be far stronger than nylon fiber.

Fenniri’s group has patented its technology and hopes to attract venture capital to launch a start-up company to exploit it.

"Purdue has a tremendous amount of technology waiting for entrepreneurs to use," he said. "What has often happened is that we
come up with technology and it just sits until it’s reinvented elsewhere and they start companies to exploit it.

"Clearly, we have to do more."

George Adams, an electrical and computer engineer who heads Purdue’s faculty planning committee for the new research facility,
said that advances in many fields are leading scientists to work at the molecular level.

"Nanotechnology is still in its infancy and not yet dominated by a particular geographic location, such as Silicon Valley dominates the
computer industry," Adams said.

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© 2002, Chicago Tribune.

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