Intel unveils high-performance silicon-laser chip

Mumbai: Intel has perfected the world's first silicon-laser chip that could enable dramatic performance improvements to computers. Researchers from Intel and the University of California said the breakthrough would help produce low-cost, high-bandwidth silicon photonics devices that can be used inside computers and data centres.

Researchers said they have combined the light-emitting properties of indium phosphide with the light-routing capabilities of silicon into a single hybrid chip, creating a chip that can transfer data by laser light.

"This could bring low-cost, terabit-level optical 'data pipes' inside future computers and help make possible a new era of high-performance computing applications," said director of Intel's photonics technology lab, Mario Paniccia. "While still far from becoming a commercial product, we believe dozens, maybe even hundreds of hybrid silicon lasers could be integrated with other silicon photonic components onto a single silicon chip," he added.

A laser based on silicon could help wider use of photonics in computers because the cost can be greatly reduced by using high-volume silicon manufacturing techniques.

Researchers have found that when voltage is applied to the hybrid chip, light generated in the indium phosphide enters the silicon waveguide to create a continuous laser beam that can be used to drive other silicon photonic devices.

The new device follows a low-temperature manufacturing technique using oxygen plasma, an electrically charged oxygen gas, to create a thin oxide layer on the surfaces of both materials.

"By combining the University of California's expertise with indium phosphide and Intel's silicon photonics expertise, we have demonstrated a novel laser structure based on a bonding method that can be used at the wafer-, partial-wafer or die-level, and could be a solution for large-scale optical integration onto a silicon platform. This marks the beginning of highly integrated silicon photonic chips that can be mass produced at low cost." said John Bowers, a professor of electrical and computer engineering at the university.

Silicon, which is widely used to mass-produce affordable digital electronics, can also be used to route, detect, modulate and even amplify light, but not to effectively generate light.

And while indium phosphide-based lasers are commonly used in telecommunications equipment, the hybrid silicon laser involves a novel design employing indium phosphide-based material for light generation and amplification while using the silicon waveguide to contain and control the laser.

With this, Intel is a step closer to "siliconising" photonics, ie, using standard silicon manufacturing processes to produce optical modulators. Intel researchers had demonstrated silicon-based optical modulator with a bandwidth in excess of 1 GHz, in 2004. They had also successfully used silicon to amplify light using an external light source to produce a continuous wave laser-on-a-chip based on the Raman effect last year.