Researchers at IBM are developing DNA nanotechnology to assemble nanoelectronic components into arrays in a bid to replace current lithographic methods of making computer chips. “IBM experimenting with DNA to build chips” (by Michael Kanellos at CNET News.com) provides an overview of both the promise and the obstacles to using DNA scaffolds to arrange nanotubes and other nanoscale components.
Scientists at IBM are conducting research into arranging carbon nanotubes—strands of carbon atoms that can conduct electricity—into arrays with DNA molecules. Once the nanotube array is meticulously constructed, the laboratory-generated DNA molecules could be removed, leaving an orderly grid of nanotubes. The nanotube grid, conceivably, could function as a data storage device or perform calculations.
“These are DNA nanostructures that are self-assembled into discrete shapes. Our goal is to use these structures as bread boards on which to assemble carbon nanotubes, silicon nanowires, quantum dots,” said Greg Wallraff, an IBM scientist and a lithography and materials expert working on the project. “What we are really making are tiny DNA circuit boards that will be used to assemble other components.”
The work, which builds on the groundbreaking research on “DNA origami” conducted by California Institute of Technology’s Paul Rothemund, is only in the preliminary stages. Nonetheless, a growing number of researchers believe that designer DNA could become the vehicle for turning the long-touted dream of “self-assembly” into reality.
Chips made on these procedures could also be quite small. Potentially, DNA could address, or recognize, features as small as two nanometers. Cutting-edge chips today have features that average 45 nanometers. (A nanometer is a billionth of a meter.)
“There is nothing else out there that we can do that with,” said Jennifer Cha, an IBM biochemist working on getting the biological and nonbiological molecules to interact.
The final quotation from IBM scientist Greg Wallraff sums up the big question—not only for using DNA nanotechnology to make chips, but also as a path toward productive nanosystems:
“Of course, the devil is in the details,” said Wallraff. “These are self-assembly procedures and error rates—missing features could be the downfall.”
—Jim
