Nanoelec Research Technological Institute (IRT) in Grenoble, France - an R&D consortium headed by CEA-Leti focused on information and communication technologies (ICT) using micro- and nanoelectronics - has announced the first co-integration of a III-V/silicon laser and silicon Mach-Zehnder modulator demonstrating 25Gbps transmission on a single channel. This transmission rate usually is achieved using an external source, over a 10km single-mode fiber (SMF).
Existing interconnect technologies, which use micro-optics integration to assemble a discrete laser and a silicon photonic circuit, will soon reach their limits and new solutions must be found to handle increasing traffic.
Integrating photonics capabilities on silicon chips is replacing currently established technologies, vastly increasing bandwidth, density and reliability, while dramatically reducing energy consumption. In the age of photonics-on-silicon, data transmission will be measured in terabits per second.
"Jointly obtained by STMicroelectronics and Leti in the frame of the IRT Nanoelec cooperation, these results - especially fabricating the laser directly on silicon - demonstrate IRT Nanoelec's worldwide leadership in III/V-on-silicon integration to achieve high-data-rate fiber-optic modules," says project manager Stéphane Bernabé. "IRT Nanoelec and its partners on this project - Leti, STMicroelectronics, Samtec and Mentor Graphics - are paving the way to integrating this technology in next-generation transceivers for optical data links," he adds.
To achieve the recent results, silicon photonics circuits integrating the modulator were processed first on a 200mm silicon-on-insulator (SOI) wafer, although 300mm wafers also could be used in the near future. Then, a 2-inch wafer of III-V material was directly bonded on the wafer. In the third step, the hybrid wafer was processed using conventional semiconductor and/or MEMS process steps to produce an integrated modulator-and-laser transmitter.
IRT Nanoelec launched its silicon photonics program in 2012, with core members Mentor Graphics, STMicroelectronics and CNRS. The program brings together, under one roof, the expertise and equipment needed to address the entire photonics-on-silicon value chain.
Leti is attending the Optical Fiber Communication Conference (OFC 2016) in Anaheim, CA, USA (20-24 March) and has a booth in the Exhibition Hall (3759).