At this week’s OFC 2015, the largest global conference and exposition for optical communications, nanoelectronics research center imec, its associated lab at Ghent University (Intec), and Stanford University have demonstrated a compact germanium (Ge) waveguide electro-absorption modulator (EAM) with a modulation bandwidth beyond 50GHz. Combining state-of-the-art extinction ratio and low insertion loss with an ultra-low capacitance of just 10fF, the demonstrated EAM marks an important milestone for the realization of next-generation silicon integrated optical interconnects at 50Gb/s and beyond.
Future chip-level optical interconnects require integrated optical modulators with stringent requirements for modulation efficiency and bandwidth, as well as for footprint and thermal robustness. In the presented work, imec and its partners have improved the state-of-the-art for Ge EAMs on Si, realizing higher modulation speed, higher modulation efficiency and lower capacitance. This was obtained by fully leveraging the strong confinement of the optical and electrical fields in the Ge waveguides, as enabled in imec’s 200mm Silicon Photonics platform. The EAM was implemented along with various Si waveguide devices, highly efficient grating couplers, various active Si devices, and high speed Ge photodetectors, paving the way to industrial adoption of optical transceivers based on this device.
“This achievement is a milestone for realizing silicon optical transceivers for datacom applications at 50Gb/s and beyond,” stated Joris Van Campenhout, program director at imec. “We have developed a modulator that addresses the bandwidth and density requirements for future chip-level optical interconnects.”
Companies can benefit from imec’s Silicon Photonics platform (iSiPP25G) through established standard cells, or by exploring the functionality of their own designs in Multi-Project Wafer (MPW) runs. The iSiPP25G technology is available via ICLink services and MOSIS, a provider of low-cost prototyping and small volume production services for custom ICs.
Imec (imec.be) performs world-leading research in nanoelectronics. Imec leverages its scientific knowledge with the innovative power of its global partnerships in ICT, healthcare and energy. Imec delivers industry-relevant technology solutions. In a unique high-tech environment, its international top talent is committed to providing the building blocks for a better life in a sustainable society. Imec is headquartered in Leuven, Belgium, and has offices in Belgium, the Netherlands, Taiwan, US, China, India and Japan. Its staff of over 2,080 people includes more than 670 industrial residents and guest researchers. In 2013, imec's revenue (P&L) totaled 332 million euro.
Imec is a registered trademark for the activities of IMEC International (a legal entity set up under Belgian law as a "stichting van openbaar nut”), imec Belgium (IMEC vzw supported by the Flemish Government), imec the Netherlands (Stichting IMEC Nederland, part of Holst Centre which is supported by the Dutch Government), imec Taiwan (IMEC Taiwan Co.) and imec China (IMEC Microelectronics (Shanghai) Co. Ltd.) and imec India (Imec India Private Limited).
About Ghent University and Intec
Ghent University, abbreviated to UGent, is one of the major universities in the Dutch-speaking region of Europe. It distinguishes itself as a socially committed and pluralistic university in a broad international perspective.
The mission of the Department of Information Technology (Intec) of Ghent University is to provide high quality education from undergraduate to postgraduate level based on excellent research. To obtain this excellence on an international level Intec focuses its research effort on carefully chosen domains so as to achieve a critical mass in each of them. In the physical layer Intec and more in particular its 85 people strong Photonics Research Group - has a focus on nanophotonic components and silicon photonics for application in telecom, datacom, sensing and biosensing.
About Stanford University
Stanford University, a leading institution in USA has had extensive interaction with imec over the years. This work resulted through interaction of Shashank Gupta a Ph.D. student in the group of Prof. Krishna Saraswat in the Department of Electrical Engineering of Stanford with IMEC.
About imec IC-link
Imec IC-link (imec.be/iclink) is responsible for connecting innovators and entrepreneurs to advanced integrated circuit technologies from the leading international foundries. It functions as imec’s main access point to the commercial activities of over 300 SMEs and 600 research institutions through its Europractice fabrication service. Its staff of over 80 people work with customers to deliver design services, prototyping, productization and volume production services, including packaging and testing, along with guidance on printed circuit board design and assembly. Imec IC-link is based in Leuven, Belgium, and is a certified TSMC value chain aggregator for Europe, The Middle East, Brazil, and India.