Reactive ion etching of low-loss channel waveguides in Al2O3 and Y2O3 layers

J. Bradley, F. Ay, Kerstin Worhoff, Markus Pollnau

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    In this work, the etching behaviour of reactively co-sputtered amorphous $Al_2O_3$ and polycrystalline $Y_2O_3$ films was investigated using an inductively coupled reactive ion etch system. In $Al_2O_3$ channel waveguides were fabricated with BCl3/HBr plasma and using a standard resist mask, while in $Y_2O_3$ channel waveguides were fabricated with Ar and using either a resist or sputter deposited $Al_2O_3$ mask layer. The etched structures in both materials exhibit straight sidewalls with minimal roughness and sufficient widths (down to 1.0 µm for $Al_2O_3$ and 1.4 µm for $Y_2O_3$) and etch depths (up to 530 nm for $Al_2O_3$ and 250 nm for $Y_2O_3$) for defining waveguides with strong optical confinement. Using the developed etch processes, single-mode ridge waveguides were fabricated in both $Al_2O_3$ and $Y_2O_3$ layers and additional losses introduced by etching, as determined by subtracting the known background losses of the un-etched films from the measured channel losses, were found to be low (< 0.5 dB/cm).
    Original languageUndefined
    Title of host publicationBook of Abstracts 33rd International Conference on Micro- and Nano-Engineering 2007
    Place of PublicationCopenhagen, Denmark
    PublisherTechnical University of Denmark
    Number of pages2
    ISBN (Print)not assigned
    Publication statusPublished - Sep 2007
    Event33rd International Conference on Micro- and Nano-Engineering, MNE 2007 - Copenhagen, Denmark
    Duration: 23 Sep 200726 Sep 2007
    Conference number: 33

    Publication series

    PublisherTechnical University of Denmark
    NumberPaper P-NS


    Conference33rd International Conference on Micro- and Nano-Engineering, MNE 2007
    Abbreviated titleMNE


    • IOMS-APD: Active Photonic Devices
    • METIS-245746
    • IR-64431
    • EWI-11285

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