Magazine article Science News

Pillars of the Thin-Film Community

Magazine article Science News

Pillars of the Thin-Film Community

Article excerpt

For a computer chip to have a chance of working properly, the thin layers of materials that make up the chip must be perfectly crystalline and flat. Now, however, researchers are making thin films with unusual microstructures that could have a host of other applications, such as sensors, magnetic recording media, or flat-panel displays. Two recent studies describe ways to create films with a microstructure reminiscent of trees growing in a forest.

At the University of Toronto, a team of scientists has succeeded in planting a forest of carbon nanotubes on an aluminum foundation. The technique not only allows the nanotubes to grow in a regular arrangement but is also "a way of mass-producing nanotubes of the diameter that you want," says study coauthor Jimmy Xu, soon to be at Brown University in Providence, R.I.

Xu and his colleagues etch an array of tiny holes into a thin piece of aluminum. Inside each hole, they deposit a cobalt catalyst. When the template is exposed to an acetylene vapor at 650 [degrees] C, carbon nanotubes, about 47 nanometers in diameter, grow out of the holes. They can reach heights of up to 100 micrometers, Xu says.

Researchers commonly make nanotubes by coursing electricity through a rod of solid carbon, which then throws off soot containing carbon molecules of many shapes and sizes. Bundles of nanotubes produced this way must be chemically separated, sorted by size, and manipulated. "That's a pain," Xu notes. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.