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Journal of Lightwave Technology

Journal of Lightwave Technology


  • Vol. 23, Iss. 8 — Aug. 1, 2005
  • pp: 2455–

Silicon Waveguide Sidewall Smoothing by Wet Chemical Oxidation

Daniel K. Sparacin, Steven J. Spector, and Lionel C. Kimerling

Journal of Lightwave Technology, Vol. 23, Issue 8, pp. 2455- (2005)

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This paper reports a new and more efficient Si waveguide sidewall smoothing process using wet chemical oxidation. Sidewall roughness is a major source of loss and an impediment to realizing high-transmission Si waveguides. The postetch multistepped approach allows for efficient smoothing (in terms of roughness amplitude reduction to material consumption) by continuous oxidation in the fast reaction-limited regime. This method reduces waveguide transmission loss without sacrificing dimensional integrity or thermal budget. In this proof-of-concept work, Si waveguide sidewall loss has been reduced from 9.2 to 1.9 dB/cm.

© 2005 IEEE

Daniel K. Sparacin, Steven J. Spector, and Lionel C. Kimerling, "Silicon Waveguide Sidewall Smoothing by Wet Chemical Oxidation," J. Lightwave Technol. 23, 2455- (2005)

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