Grenoble-based CEA-Leti (the French government’s Laboratory for Electronics & Information Technology) reckons that Europe is strongly positioned to design and manufacture volume silicon photonics devices because of the success of the recently completed program HELIOS (pHotonics ELectronics functional Integration on CMOS).
Coordinated by Leti, the €8.5m European Commission project developed a complete design and fabrication supply chain for integrating a photonic layer with a CMOS circuit, using microelectronics fabrication processes.
HELIOS also demonstrated a complete design flow, integrating both silicon photonics device design and electronic/photonic system design in an EDA-compatible framework.
“It is strategically important for Europe to maintain photonic chip-design and chip-integrating functions to compete with other countries and to encourage innovation by European microelectronics companies,” says Leti’s CEO Laurent Malier. “HELIOS’ success in creating the essential building blocks for integrating photonics with CMOS circuits and making the process available to a variety of users underscores the key role that broad European technological cooperation plays in a very competitive global business environment,” he adds.
Thomas Skordas, head of the EC’s photonics unit, says HELIOS has shown the great potential that silicon photonics has in many different applications, such as data communications.
“The technology roadmap of silicon photonics becomes clearer now,” he adds. “Europe will have to move fast to become competitive in this new field,” Skordas says. “Strategies for the industrialization of silicon photonics are currently being discussed in the context of Horizon 2020, the EU's new framework program for research and innovation for 2014-2020.”
Because of the cost advantages of integrating photonic and electronic functions on the same chip, silicon photonics is seen as being key to developing optical telecommunications or for optical interconnects in microelectronic circuits. CMOS photonics may lead to low-cost solutions for a range of applications such as optical communications, optical interconnections between semiconductor chips and circuit boards, optical signal processing, optical sensing, and biological applications.
Launched by the European Commission in 2008, HELIOS focused on developing essential building blocks like efficient optical sources (silicon-based and heterogeneous integration of III-V on silicon), integrated lasers, high-speed modulators and photo-detectors. The project, which had 20 members, also combined and packaged these building blocks to demonstrate complex functions that address a variety of industrial needs.
These include a 10Gb/s modulator integrated with an electronic BiCMOS driver, a 16x10Gb/s transceiver for WDM-PON applications, a photonic QAM-10Gb/s wireless transmission system and a mixed analog-and-digital transceiver module for multi-function antennas.
The building blocks also led to results exceeding the original specifications:
high-performance passive devices were obtained and introduced in the demonstrators (rib/strip waveguides transitions with less than 0.2dB losses, grating couplers with 1.6dB losses, inverted taper couplers with 1dB losses, AWG and micro-ring based de-multiplexers); the wafer-level integration of laser by III-V/Si bonding led to the demonstration of single-mode operation with 3dBm output power, 30dB SMSR, Ith < 35mA in continuous-wave (CW) mode; 40G carrier depletion silicon modulators were demonstrated in Mach-Zehnder interferometer (MZI), ring, slow wave, interdigitated modulators configuration. an integrated tunable laser–Mach-Zehnder modulator working at 10Gb/s.
The work of the HELIOS consortium led to more than 170 publications and communications in peer-review journals and international conferences.
Project partners included CNRS, Alcatel Thales III-V lab, Thales, University of Paris-Sud, 3S Photonics and Photline Technologies in France; IMEC in Belgium; Phoenix BV in The Netherlands; IHP and the University of Berlin in Germany; ams AG and the University of Vienna in Austria; IMM and the University of Trento in Italy; the University of Valencia, the University of Barcelona and DAS Photonics in Spain; and the University of Southampton and the University of Surrey in the UK.
