Abstract

Monolithic integration of optoelectronics with electronics is a much-desired functionality. Here, we demonstrate that it is possible to realize low-loss Ge quantum-well photonic interconnects on Si wafers. We show that Ge-rich Si1–xGex virtual substrates can act as a passive, high-quality optical waveguide on which low-temperature, epitaxial growth of Ge quantum-well devices can be realized. As a proof of concept, the photonic integration of a passive Si0.16Ge0.84 waveguide and two Ge/SiGe multi-quantum-well active devices, an optical modulator and a photodetector was realized to form a photonic interconnect using a single epitaxial growth step. This demonstration confirms that Ge quantum-well interconnects are feasible for low-voltage, broadband optical links integrated on Si chips. Our approach can be extended to any kind of Ge-based optoelectronic device working within telecommunication wavelengths as long as a suitable Ge concentration is selected for the Ge-rich virtual substrate.

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Acknowledgements

This research received funding from the French ANR under project GOSPEL (Direct Gap Related Optical Properties of Ge/SiGe Multiple Quantum Wells) and from the European Commission (EC) through project Green Silicon. The fabrication of the device was performed at the nano-center CTU-IEF-Minerve, which is partially funded by the ‘Conseil Général de l'Essonne’. This work was partly supported by the French RENATECH network.

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Affiliations

  1. Institut d'Electronique Fondamentale, Université Paris-Sud, CNRS UMR 8622, Bâtiment 220, 91405 Orsay Cedex, France

    • Papichaya Chaisakul
    • , Delphine Marris-Morini
    • , Mohamed-Said Rouifed
    • , Paul Crozat
    •  & Laurent Vivien
  2. L-NESS, Dipartimento di Fisica del Politecnico di Milano, Polo di Como, Via Anzani 42, I-22100 Como, Italy

    • Jacopo Frigerio
    • , Daniel Chrastina
    • , Stefano Cecchi
    •  & Giovanni Isella

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Contributions

P.Ch., D.M.-M. and L.V. conceived the project. P.Ch. designed and fabricated the tested devices, conducted the experiments and performed optical simulations. P.Ch. and D.M.-M. analysed the experimental data. J.F. carried out epitaxial growth and band diagram calculations. D.C. and S.C. performed HR-XRD measurements and analysis. S.C. participated in the epitaxial growth. P.Cr. participated in device characterization. All authors contributed to manuscript preparation. D.M.-M., G.I. and L.V. supervised the project.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Delphine Marris-Morini.

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DOI

https://doi.org/10.1038/nphoton.2014.73

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