Faster plastic circuits for flexible computing
Flexible materials used to build electronic displays are not mainstream yet, even if new products are launched almost every week. Until today, they needed to be powered by processors which couldn't been implanted on the displays themselves. But now, Technology Review reports that thanks to research done at Sarnoff Corporation in Princeton, NJ, and Columbia University, flexible plastic circuits can now operate at speeds up to 100 megahertz. And even if these processing speeds are a hundred times faster than the ones previously achieved, the researchers think their plastic circuits can easily become more powerful. This opens the way to large displays easily carried in a car trunk and even to real wearable computing devices.
Here are the opening paragraphs of the MIT Technology Review article.
Electronic displays can now be made on flexible materials, and they're appearing in limited applications. But the high-speed processing power to run them still requires expensive -- and rigid -- silicon wafers. If all the components could be built onto the same flexible surface, though, it could save money, improve reliability, and perhaps allow for radical new designs.
Researchers have built working circuits now on plastic that are fast enough to make this integration possible. At Sarnoff Corporation in Princeton, NJ, and Columbia University, researchers have succeeded in operating circuits at 100 megahertz -- as much as a hundred times faster than previous ones on plastic.
Here is a link to a page about flat-panel displays at Sarnoff.
And below is a photograph of pentacene Thin Film Transistor OTFTs (for "Organic Thin Film Transistor) on a flexible PEN (for "PolyEthylene Naphthalate") film (Credit: Sarnoff Corporation).
What kind of applications can we expect from these new faster plastic circuits? New military applications of course.
The Sarnoff/Columbia advance could lead to displays measuring three meters or more diagonally that can also be rolled up and easily transported. One possible market: the Pentagon, which is interested in such a device for use in field command centers.
Fast transistors on plastic could also lead to portable phased-array antennas. Such antennas direct a transmission at a precise target, which saves power and makes communications harder to intercept. Today's phased-array antennas cost $100,000 and take up at least one square meter, meaning they have to be mounted to a vehicle, according to Michael Kane, a solid-state devices researcher at Sarnoff.
Of course, other applications can be possible, and some of them are not even on the drawing board according to Tayo Akinwande, an electrical engineering professor at MIT.
The technology might someday be incorporated into clothing, or speakers with microdevices that "shape sound," Akinwande says. The most interesting applications, he says, may be completely different from anything we have now. "You're not going to use it to try to make a microprocessor," he says. "If you did that, you'd lose your shirt. But you could try to do some things that regular silicon cannot do right now. And that is left to our imagination."
I guess we'll have to wait for several years before this technology can be integrated in the devices we're using daily..
Sources: Kevin Bullis, Technology Review, December 13, 2005; and various web sites
You'll find related stories by following the links below.