Silicon photonics is an evolving technology that allows data to be transferred between computer chips by optical rays, which are able to carry larger amounts of data over shorter periods of time than conventional electrical conductors. Historically, the excessive energy consumption of the lasers used to generate the infrared beams that carry the data posed a serious challenge for the developers of silicon photonic devices. Furthermore, dissipation of heat within the silicon reduces the efficiency of lasing — thus limiting the devices’ effectiveness. For these reasons, optical computers using silicon chips have relied on external lasers for their operation. In recent years, however, such problems have been overcome by new techniques that include combining silicon with indium phosphide to improve the infrared-transmission capacity of the device, boosting data relay speeds above 25 gigabits per second (Gbps).
In collaboration with Japanese optical telecommunication network systems-developer Fujikura Ltd, the A*STAR Institute of Microelectronics (IME) has now pioneered the world’s first 40 to 60 Gbps silicon-based optical modulators. These devices permit high-speed transfer of data over long distances in an advanced — multilevel — modulation format and greatly increase the total data communication throughput for a given optical channel. Additionally, compared to conventional non-silicon-based modulators, such as those of lithium niobate, the new modulators created by the IME and Fujikura have a much smaller energy footprint and are significantly cheaper to fabricate.
“We are proud to have jointly achieved this breakthrough with Fujikura,” says Dim-Lee Kwong, professor and executive director of the IME. “This will fuel the design and development prospects of next-generation, long-haul telecommunication systems as well as truly bringing low-cost, high-performance optical communications to the masses.” The researchers presented their remarkable findings at OFC/NFOEC, a global conference and exposition on optical communications and networking held in the United States, in March 2013.
Founded in 1991 as an institute for research in advanced engineering, the IME works to stimulate the microelectronics industry in Singapore by undertaking research and development in microelectronics, and supporting the needs of the industry through training and development of skilled personnel. One of the IME’s goals is to encourage semiconductor companies to conduct small-scale pilots of prototypes. Under Kwong’s leadership, the IME has fostered partnerships with more than 50 multinational firms ranging from major Japanese conglomerates to Forbes 500 companies. To date, the IME has successfully generated an impressive portfolio of internationally approved patents.
The strategic partnership between the IME and Fujikura was forged in 2006 to develop technologies for optical telecommunications. The current innovation is the latest in a line of success stories born of the relationship, allowing the IME and Fujikura to prove that reaching ultrahigh performance levels on a silicon-platform technology is now a reality. The advance is expected to provide a huge boost to the development of ultrahigh-bandwidth optical communications. Kenji Nishide, general manager of the Fujikura Optics and Electronics Laboratory, is excited about the recent breakthrough. “We have opened the door to expand silicon-based modulators in next-generation optical telecommunication networks,” he says.
The IME and Fujikura are now partnering to create more prototypes of highly integrated photonic chips able to accommodate higher transmission capacities and spectral efficiencies, and working closely to refine the production cycle for the new modulators with the aim of bringing the new chips to market as early as 2015.
About the Institute of Microelectronics
The Institute of Microelectronics (IME) is a research institute of the Science and Engineering Research Council of the Agency for Science, Technology and Research (A*STAR). Positioned to bridge the R&D between academia and industry, the IME’s mission is to add value to Singapore’s semiconductor industry by developing strategic competencies, innovative technologies and intellectual property; enabling enterprises to be technologically competitive; and cultivating a technology talent pool to inject new knowledge to the industry. Its key research areas are in integrated circuits design, advanced packaging, bioelectronics and medical devices, MEMS, nanoelectronics, and photonics.
About Fujikura Ltd
Fujikura Ltd is a 128-year-old multinational company based in Tokyo, Japan, with businesses in optical telecommunication network systems, power transmission systems, electric wires and cables, magnetic wires, automotive wiring harnesses and related products, and electronic components. Its annual revenue, as of the last fiscal year, stands at about JPY 500 billion.