Ever have the urge to put your fist through a computer screen? If so, you may want to wait a few more years and limit your damage.
Bell Labs, the R&D subsidiary of Lucent Technologies, is collaborating with a Norwegian company on a project to make plastic memory chips for use in computer display screens and smart cards. The primary advantage would be thinner screens that are more rugged and more flexible than today's liquid crystal displays, which use glass as a medium.
"What we have is a plastic, or organic, material that plays the role of the semiconductor itself," said V. Reddy Raju, a chemical engineer at Bell Labs, Murray Hill, New Jersey. But the research for the project is in a very early stage, and probably won't result in any commercial technologies for at least three to five years, said Raju.
Researchers in the lab said the printed plastic circuit prototypes conduct electricity just like a sliver of silicon does in a conventional computer. Raju's colleagues discussed their preliminary findings this afternoon at a session of the American Chemical Society annual meeting in Dallas.
Chipmakers have for decades searched for possible alternatives to the silicon semiconductor. Gallium arsenide was once considered an option, but it never made the grade. Since then, Bell Labs scientists have been working to develop a material that is more flexible than silicon, and able to be produced en mass.
"Scale-up would also be relatively straightforward. We could start with a small sheet (of plastic) and move up to a much larger sheet," said Raju. "Our long-term dream is to make this into a semi-continuous manufacturing process, where sheets of plastic would roll off the press as newspaper print rolls off the printing press."
At Bell Labs, scientists have been able to print functioning circuits on flexible sheets of plastic using inexpensive screen printing techniques. The process involves spraying liquids instead of printing, using less material and cutting down on costs. Bell Labs has also developed an array of polymer materials for possible use in the project.
"We have identified and synthesized several materials that will work as the constituent part. And we are learning to put it together in an integrated fashion, so it works like an integrated circuit, with many circuits working together," said Raju.
The smallest plastic chip achieved by the Bell Labs' scientists for the printed plastic transistor is 75 microns, much larger than the 0.25 micron in today's fastest silicon transistors. Opticom ASA, the Oslo-based company working with Lucent, has developed the plastic processing techniques, patterning techniques, and memory architectures which could be used for a commercial product.
Though Bell is the first company in the US to announce work on a plastic memory chip, the company is not alone in the field. Philipps Electronics, the Dutch manufacturer, is said to be working in the field, and a French government laboratory also has a similar project in the works.
