IBM taps new technology to build faster chips

In a process known as silicon-on-insulator (SOI), transistors sit atop a glass layer instead of on traditional silicon. The use of glass prevents electrons that flow through a transistor from escaping, increasing efficiency and reducing power consumption.

"The electrons that are supposed to go through a switch, some get wasted into silicon," said Bijan Davari, IBM's vice president of semiconductor research and development. "(SOI) prevents the electrons from being lost in the silicon."

As previously reported, SOI is one of a recent spate of chip manufacturing ideas from IBM. Other advances include the use of copper and an advanced insulation material called "low-k" dielectrics, the use of which IBM announced in April.

While these chip advances are seen as technologically difficult, they are essential to the process of shrinking chips into ever-smaller designs.

"If you look at the stuff it takes to keep this moving down the road in terms of performance, SOI is a huge step," said Fred Zieber, analyst and president of Pathfinder Research.

In 1998, IBM said it was working on developing SOI, yet today's announcement will showcase the first machines to actually take advantage of the new technology. The new servers are part of IBM's AS/400 line.

The new AS/400e 800 server line should be available in August, IBM said. The company also plans to cut prices on its AS/400e 700 series servers.

Zieber estimated that other leading chipmakers are about two years behind IBM in bringing SOI technology to market. Sources have said Hewlett-Packard will use IBM's SOI technology in its upcoming PA-8700 chip.

Zieber agreed that SOI is a significant advance in improving chip performance. The use of smaller transistors has helped to speed semiconductor performance in the past, yet Zieber said that even that method is beginning to show diminishing returns.

IBM?s decision to use the SOI process follows the company?s move from aluminum to copper in chips. IBM first brought copper chips to market in 1998.

Zieber said that Texas Instruments and Motorola are now considering using SOI technology in future chip development.

"Clearly people are thinking about it," Zieber said.

He added that IBM does face a number of technological hurdles. For one, circuits must be redesigned to accommodate the new material. Additionally, the glass used in the chip must be as pure and defect-free as standard silicon, Zieber said.

"It's tougher than making a single change," Zieber said. "It's a big engineering job and one that takes a certain amount of time."

These new chips are expected to run 20 to 30 percent faster and use less power than traditional chips, Davari said. To take advantage of these improvements, Davari added that handhelds could be expected to incorporate SOI-based chips in the future.

"We think this is going to be a pervasive technology around the industry," Davari said. "The industry will move to it; it?s just a matter of time."

IBM plans to introduce SOI into its RS/6000 servers this fall and will also use the technology for its next-generation Power4 processor.