AUTHOR=Debnath Kapil , Khokhar Ali Z. , Boden Stuart A. , Arimoto Hideo , Oo Swe Zin , Chong Harold M. H. , Reed Graham T. , Saito Shinichi 

TITLE=Low-Loss Slot Waveguides with Silicon (111) Surfaces Realized Using Anisotropic Wet Etching

JOURNAL=Frontiers in Materials

VOLUME=Volume 3 - 2016

YEAR=2016

URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2016.00051

DOI=10.3389/fmats.2016.00051

ISSN=2296-8016

ABSTRACT=We demonstrate low-loss slot waveguides on silicon-on-insulator (SOI) platform. Waveguides oriented along the (11-2) direction on the Si (110) plane were first fabricated by a standard e-beam lithography and dry etching process. A TMAH based anisotropic wet etching technique was then used to remove any residual side wall roughness. Using this fabrication technique propagation loss as low as 3.7dB/cm was realized in silicon slot waveguide for wavelengths near 1550nm. We also realized low propagation loss of 1dB/cm for silicon strip waveguides.