Intel preps transistor for 20GHz+ CPUs

Terahertz burst

Intel boffins will next week describe two new techniques that, if implemented in mainstream chips,
may herald the arrival of 25GHz and faster processors by 2005.

They will outline a new transistor structure and the material that makes it more efficient than existing models.

The transistor - called by the researchers a "depleted substrate transistor", but by Intel's spin doctors "Terahertz technology" - is a variant of silicon-on-insulator technology. Current SOI methods bond a thin layer of silicon onto a thin layer of insulating material, the idea being to minimise the effort - ie. the power - required to switch the transistor on and off, yet prevent the device from leaking current thus drawing extra power and increasing the level of electronic 'noise' within the device.

Intel's version of the SOI process uses thinner insulator and more depleted - ie. 'electron-hungry' - silicon. The upshot is a transistor that can switch on and off more quickly and leaks less current - about 100 times less leakage, Intel claims - when in an 'off' state then current chip transistors.

The thinner insulation is made possible through a high k dielectric material, applied molecule-thick layer by molecule-thick layer.

The result: faster, more efficient operation than generates less heat. Additionally, less power is consumed in the transistor's operation. Scale that from one transistor to the millions of such devices that make up a modern microprocessor and chip designers can increase clock speeds massively with no corresponding increase in heat generation and power consumption.

Alternatively, chips can be produced that offer much less of a speed boost over today's processors, but in return draw far less power, a feature of essential importance to battery-powered devices.

According to Intel's director of components research, Gerald Marcyk, the new techniques will boost processor clock speeds by "ten times... with no increase in power consumption". That's rather less than the thousandfold increase the company's 'Terahertz' tag suggests, which derives from the increased speed of the individual transistor. Sure, a whole chip might be able to get up to that speed too, but at what level of power consumption and heat dissipation? Rather more than is healthy for the chip, we guess.

Intel researchers will reveal more at the International Electron Device Meeting in Washington, DC on 3 December. ®