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A SPEED limit on future computers may be broken thanks to a new breed of
insulating materials that makes microchips work much faster.

Insulating layers of silicon dioxide play a key role in microchips. The
thinner the layers the faster the circuits switch on and off, processing data.
But the downside is that thinner layers let current through, causing unwanted,
corrupting “noise”.

To plug these leaks you need an insulator with a high “dielectric constant”.
Such compounds do exist, but no one’s been able to grow them on chips without
defects.

Now Rodney McKee of the Oak Ridge National Laboratory in Tennessee has
managed to lay down high-quality layers of compounds called perovskite oxides.
These have dielectric constants hundreds of times higher than silicon
dioxide.

They also have a unique property—they can hold an internal electric
field for an amazing 15 years even with no power. It could mean computer logic
gates remain on or off for ages—even if you pull the plug. “That’s an
entirely new function in a transistor,” says McKee.

And electronics is just the start. Because the compounds are transparent,
their optical properties mean “waveguides” could one day be grown easily on
chips, speeding signal processing in optical telephone networks.

Microchip giant Motorola has taken out a licence on the new technology.