New silicon LED could eliminate network bottleneck

Scientists in the United Kingdom have developed a silicon-based light-emitting diode (LED) that could lead to a more seamless link between semiconductors and optical data networks.

Until now, converting the electrons – which carry information in silicon chips into the photons that is the currency of optical fibre networks – has been a bottleneck. The semiconductor industry has been seeking an efficient way to turn silicon itself into a light emitter. Today’s LEDs are commonly made of other semiconductors, such as gallium arsenide, and cannot be mounted directly on silicon chips, setting limits on speed and miniaturization.

Researchers at the University of Surrey have found such a technique: a method of making silicon glow at room temperature, producing light almost as efficiently as the current generation of LEDs, said Kevin Homewood, who designed the prototype along with colleagues. Their findings are published in Thursday’s edition of the journal Nature.

Homewood said the invention could reach end users fairly quickly. “It actually uses more or less standard industry technology, (so) they could almost do it tomorrow… but of course it will take some time to redesign the chip architecture.”

He added that he and his colleagues patented their technique “a few months ago,” but had waited to discuss it publicly until publishing their research. “We expect there to be quite a bit of industry interest,” he said.

The University of Surrey, in Guildford, England, can be reached at