CEA (Commissariat à l’Energie Atomique et aux Energies Alternatives) is a French Governmental Research Organisation (15000 employees) devoted to both fundamental and industrial Research & Development. Within CEA, CEA-LETI is one of the major European research centres for applied electronics. It is located in Grenoble where it operates 11000 m²-State-of-the-Art CMOS clean rooms, 200 and 300 mm wafer size, and the 200 mm MEMS microsystems platform, with equipment worth some 200 M€. Nearly 1,600 men and women are serving innovation and the transfer of technology in key domains, with ST microelectronics as the main industrial partner. CEA-LETI has sparked the creation of nearly thirty high-technology start-ups, including Soitec, world leader in the development/ production of Silicon on insulator wafers.

As a pioneer in Research & Development in Silicon Photonics (2002) CEA-Leti has developed strong expertise and know how in device design, integration and test, including Ge-on-Silicon photodetectors and heterogeneous III/V-on-Silicon lasers. Having achieved the development of world-record-output-power lasers, and 200mm-wafer-size processing, CEA is considered as a leading institute in the field.

Main tasks in PICTURE:

Within the PICTURE project, CEA will enhance its 200 mm silicon photonics platform by implementing a new III-V on Silicon hybrid bonding scheme using a thin oxide bonding layer to obtain optimized hybrid active devices such as hybrid III-V on Si lasers with improved power efficiency and thermal behaviour, very efficient and low power consumption III-V on Si hybrid capacitive modulators and photodiodes. CEA will develop multi-die bonding technology in order to use the expensive III-V material only where it is necessary for active devices and to use III-V epitaxial stacks based on QW or QD active layers separately optimized for the laser, the modulator and the photodetector. Importantly, CEA will develop the whole fabrication process of III-V on Si photonic integrated circuits on its 200 mm CMOS platform to demonstrate the industrial manufacturability. In addition CEA, will work on the design of efficient, low-voltage and low-power consumption hybrid III-V on Si modulators and perform characterization of all the passive and active building blocks up to 67 GHz operation on its Automatic Prober stations.

CEA has developed a 200 mm Silicon photonics platform including passive components such as waveguides, single polarization and polarization-splitting fiber couplers, multiplexers /demultiplexers and active components operating at 25 Gb/s such as Si modulators based on a PN junction in depletion and Ge photodetectors. CEA has developed an expertise in the design of all these components and in particular on the design of silicon modulators based on various junction types such as PN, PIN and capacitive junctions.

CEA has also successfully developed the integration of III-V lasers DBR and DFB lasers based on the direct bonding of III-V wafers on Silicon, and their integration with silicon modulators.

Dr. Karim Hassan, project board member for LETI of PICTURE  received his PhD degree in physics from the University of Burgundy, Dijon, France, in 2013 on the development of thermo-optical plasmonic routers for telecom applications in the framework of the FP7 project PLATON.  He joined CEA-Leti in 2014 where he works currently on silicon photonics as research fellow (H2020 COSMICC, ANR IRT-Nanoelec) and manager of the FP7 project SEQUOIA. His research interest includes the design, fabrication, and characterization of silicon photonics circuits, hybrid III-V on silicon laser sources, and topological optimization for nanophotonics. He has authored or coauthored more than 50 journal publications, conference papers and patents.

The following projects are among those referring to silicon photonic integration carried out at LETI