February 16, 2005

Editor's Note: Mario Paniccia, director of Intel's optical technology department and leader of the Intel team that developed the continuous wave all-silicon laser, received his doctorate in physics from Purdue in 1994. Intel's full release is available online.

Latest Breakthrough: A Continuous Silicon Laser

In a paper published February 17, 2005 by the prestigious scientific journal Nature , Intel researchers disclosed the development of the first continuous wave all-silicon laser using a physical property called the Raman Effect. They built the experimental device using Intel's existing standard CMOS high-volume manufacturing processes. This is the third silicon photonics paper Intel has published in Nature in the past year, beginning with the modulator breakthrough in February 2004.

In this latest paper, Intel researchers describe how they incorporated a novel diode-like structure (technically called a PIN — P-type/Intrinsic/N-type device) into the silicon cavity laser. This solved the "two photon absorption" problem that caused early versions of the device to only achieve lasing for an infinitesimal fraction of a second before shutting off. Like the first laser developed in 1960, Intel's device uses an external source (a laser) to supply the initial energy. The PIN device combined with the Raman Effect produces a continuous laser beam at a new wavelength.

The breakthrough device could lead to such practical applications as optical amplifiers, lasers, wavelength converters, and new kinds of lossless optical devices. A low-cost all-silicon Raman laser could inspire innovation in the development of new medical, sensor, and spectroscopy devices.

Why Intel Is Researching Photonics

Over the next 5 to 10 years, the computing and communications industries face increasing challenges to deliver more data faster. Consumers will be downloading full-length movies, not just photos and music files. People will also require faster access to these large amounts of data. While Intel® microprocessors are projected to meet these future demands, the bandwidth of the interconnects needs to be increased to meet the speed of the microprocessors.

One potential solution is photonics. Photonics offers much greater bandwidth than traditional copper networks and can carry multiple signals simultaneously without interference. Unfortunately, today's commercial photonic devices are made from exotic materials such as indium phosphide and gallium arsenide. This makes them difficult to manufacture and assemble, and consequently expensive. This high cost limits the use of traditional photonic devices to special applications such as long-haul telecommunications and wide area networks.

Making Photonics Affordable

Intel is focusing on ways to "siliconize" photonics and bring the benefits of Intel's volume manufacturing expertise to optical communications. Intel's goal is to make integrated, inexpensive photonic devices out of silicon instead of the exotic materials used today.

By demonstrating how optical modulators can be made out of silicon using Intel's standard manufacturing processes in an existing fab, Intel researchers have removed a significant cost barrier in photonics. The next step is integrating entire photonic devices on a chip with digital intelligence. This should pave the way to produce photonics products based on silicon.