Date: 09/12/2008

Intel advances in silicon photonics by developing Avalanche Photo Detector (APD)

Intel researchers have achieved record performance using a silicon-based Avalanche Photodetector (APD) to receive optical signals. APD is a light sensor with improved sensitivity by detecting light and amplifying weak signals as light is directed onto silicon. This advancement could lower costs and improve performance as compared to commercially available optical devices. The research results were published in Nature Photonics. Using silicon based photodetectors and lasers the data-transmission between various parts inside the chip and outside the chip can be made via optical tube/wire to increase processing performance and speed.
Silicon Photonics aims to address future bandwidth needs of data-intensive computing applications such as remote medicine and lifelike 3-D virtual worlds. Ultra-fast transfer of data will be essential for future computers powered by many processor cores. Silicon Photonics-based technology could deliver higher-speed mainstream computing at a lower cost. Intel is spearheading the research by delivering few breakthroughs such as fast silicon modulators and hybrid silicon lasers.
A team led by Intel researchers created the silicon-based APD. This APD device used silicon and CMOS processing to achieve a "gain-bandwidth product" of 340 GHz -- the best result ever measured for this key APD performance metric. This opens the door to lower the cost of optical links running at data rates of 40Gbps or higher and proves, for the first time, that a silicon photonics device can exceed the performance of a device made with traditional, more expensive optical materials such as indium phosphide.
"This research result is another example of how silicon can be used to create very high-performing optical devices," said Mario Paniccia, Ph.D., Intel Fellow and director of the company's Photonics Technology Lab. "In addition to optical communication, these silicon-based APDs could also be applied to other areas such as sensing, imaging, quantum cryptography or biological applications."
Intel worked with industry and academic collaborators, and the research was jointly funded by Defense Advanced Research Projects Agency (DARPA). Numonyx, a leading maker of NOR, NAND, RAM and phase change non-volatile memory technologies, provided manufacturing and process expertise.
Prof. Joe Campbell of the University of Virginia and Prof. John Bowers of the University of California, Santa Barbara, both APD experts, provided consultation and assisted with testing.