IBM Touts New Chip Transistor Design

IBM on Monday announced it has developed a new transistor design for microprocessors that will boost performance and reduce power consumption.

IBM on Monday announced it has developed a new transistor design for microprocessors that will boost performance and reduce power consumption.

The disclosure comes less than a week after Intel Corp. revealed a similar research effort aimed at overcoming potential obstacles to building ever faster and more energy efficient computer components. The two leading chip manufacturers are touting their separate initiatives this week at the International Electron Device Meeting (IEDM) in Washington D.C.

IBM researchers said their "double-gate" transistor—a microscopic on/off switch that forms the heart of integrated circuits—will be smaller and operate twice as fast as todays conventional transistors.

Shrinking the size of a transistor is one key to building faster processors, with chipmakers packing literally tens of millions of the electronic switches onto a single die. But as transistors are shrunk to once unimaginable sizes, already as tiny as 0.06 microns—a human hair is about 50 microns wide—chipmakers are nearing the physical limits of conventional designs.

"Other than getting smaller, the basic transistor has largely gone unchanged for decades," said Bijan Davari, vice president of semiconductor development at IBM Microelectronics, in East Fishkill, NY. "It has now been shrunk nearly to a point where it will cease to function."

One of the major obstacles in designing smaller transistors is how to prevent electricity from seeping out of components, which becomes a bigger problem as the parts are made ever smaller. Energy leakage causes processors to consume more power and heat. In fact, using present designs, processors in a few years would literally run so hot they would melt metal.

To address that issue, IBM is utilizing new materials, such as silicon on insulator (SOI), which it already uses in its chips, to shield components and reduce energy leakage.

"SOI is changing the rules in semiconductors," Davari said. "SOI allows us to change the basic design of the transistor, permitting further shrinkage and other improvements."

Within a transistor, an element called a "gate" controls the electrical flow through the transistor. As transistors continue to shrink, it becomes more difficult for a single gate to effectively control switching.

In IBMs double-gate transistor, the channel is surrounded by two gates, which gives its twice the control over the current and enables significantly smaller, faster and lower-power circuits.

The work on double-gate transistors is the culmination of a multi-year collaborative effort between the IBM Research and Microelectronic Divisions.

Other IBM papers being presented at the conference include: a 2THz (terahertz) SOI-based transistor; the smallest SRAM cell ever built at 1.8 square microns; and the first ever paper on carbon nanotube transistors at the IEDM, showing that carbon nanotube transistors may perform better than silicon transistors.