Grenoble, France--CEA-Leti and III-V lab, a joint lab of Alcatel-Lucent Bell Labs France, Thales Research and Technology, and CEA Leti, have demonstrated an integrated tunable laser on silicon (Si); a milestone, they say, towards fully integrated silicon photonics transceivers.
The source on Si incorporates a hybrid III-V/Si laser fabricated by direct bonding, with 9 nm wavelength tunability, and a Si Mach-Zehnder modulator with high extinction ratio (up to 10 dB), for excellent bit-error-rate performance at 10 gigabits per second (Gb/s or Gbps). The results were obtained in the frame of the European funded project HELIOS (www.helios-project.eu), with the contribution of Ghent University-IMEC for the design of the laser and University of Surrey for the design of the modulator.
CEA-Leti and III-V lab also demonstrated single wavelength tunable lasers, with 21mA threshold at 20°C, 45 nm tuning range and side mode suppression ratio larger than 40 dB over the tuning range.
Silicon photonics is a very powerful technology, and CEA-Leti and III-V lab say they have made a significant breakthrough in its development by integrating on the same chip complex devices such as a fully integrated transmitter working above 10 Gb/s or a tunable single wavelength laser.
Based on the heterogeneous integration process developed by the CEA-Leti and III-V lab, III-V materials such as InP can be integrated onto silicon wafers. The fabrication process starts on 200mm Silicon on Insulator (SOI) wafers where the silicon waveguides and modulators are fabricated on CEA-Leti 200mm CMOS pilot line.
"We are proud to jointly present with III-V lab the results of the integrated silicon photonics transmitter and the tunable laser," said Laurent Fulbert, photonics program manager at CEA-Leti France. "The ability to integrate a tunable laser, a modulator and passive waveguides on silicon paves the way of further developments on integrated transceivers that can address several application needs in metropolitan and access networks, servers, data centers, high performance computers as well as optical interconnects at rack-level and board-level. We are pleased to bring our contribution to these state-of-the-art results which can truly revolutionize optical communications."