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Lighting and displays

Silicon Photonics

CEA-Leti's silicon photonics platform allows miniaturization, power efficiency, cost reduction and scalability of photonic integrated circuits (PIC). Pioneering silicon photonics for 20 years, CEA-Leti has designed a technology toolbox featuring state-of-the-art performance for communication, computing and sensing.

Published on 12 March 2021

SOI Technology

The versatile silicon photonics platform offers a broad range of processes on 200 mm and 300 mm wafers, that leverage world-class pre-industrialization equipment. CEA-Leti's fabrication platform enables large-scale integration of active and passive devices, with amorphous Si, SiGe and Ge integration, in a flexible CMOS compatible process. 
  • Photonics SOI substrate with 220 nm or thicker Si
  • Selective Ge epitaxy
  • 6 implant levels for p-type and n-type for modulators and doped Si heaters
  • 3 silicon patterning steps for Si heights of 0, 65, 165 and 310 nm (193nm immersion lithography)
  • 100nm standard smallest feature size
  • Silicide modulator contacts
  • Metal heater
  • Two-level metal interconnect
  • Deep trench for edge couple

Silicon Nitride technology

Beyond SOI, this versatile photonics platform also offers PECVD SiN and LPCVD SiN technologies. This convergence of various photonic platforms combined into CEA-Leti's platform helps combining the advantages of each material and addressing numerous applications from visible to mid-infrared with the same technology. 
  • PECVD SiN: for low thermal shift and low refractive index layer to be combined with Silicon platform
  • LPCVD SiN : for Ultra-Low Loss circuits, non-linear optics, UV to NIR applications


III-V on Si heterogeneous integration

  • Heterogeneous integration of III-V on Si enables large-scale integration of lightsources. Collective die-to-wafer bonding of III-V on Si is performed with one or several different III-V epi layers enabling epi layers to be optimized for each laser and modulator.
  • This versatility offers unique PIC integrations and competitive solutions.
  • Back-end of line processes are available for an integration of PIC with Electronic Integrated Circuits. Co-packaging solutions include 3D post-processes such as UBM, bumps, µ-pillars, photonics Through Silicon Via (TSV).
  • Access to the platform is possible through MPW with broker EuroPractice / CMP or dedicated run.




Telecom, Datacom, 5G infrastructures, quantum technologies for cybersecurity


Computer communication for High Performance Computing (HPC), quantum computing and neuromorphic computing for AI


​Gas sensing, Biosensors, structural health monitoring and 3D sensing such as LIDAR

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