Tuesday, May 13, 2008

Smoothing Out Nano Edges

Continued from page 1

By Stephen Ornes

Of the three ways to use SPEL described by Chou and Xia, who is now at the Information and Quantum Systems Laboratory at Hewlett Packard Labs, Chou says that the one called "guided SPEL" is the most exciting. During that process, a quartz plate is placed above the flawed material, with a small gap in between. The laser passes through the plate and melts the material, which then rises to meet the plate. (Chou says that he does not completely understand the electrostatic interaction that explains why the material rises and narrows.)

This process produces smooth sides and a flat top to the line of metallic material. In addition, it makes the material taller and narrower, which means that microchip manufacturers will be able to make a denser chip.

The process has some limitations. When nanostructures get so small that they are the same size as the defects, for example, SPEL won't be able to help. Nonetheless, Chou says that the small, regular structures that emerge from SPEL have already caught the attention of major chip manufacturers.

"The semiconductor manufacturing people do an incredibly good job at this right now," says Karl Berggren, an associate professor of electrical engineering at MIT, "but they may be able to take advantage of this new trick, to push things even further."