OSA's Digital Library

Optics Letters

Optics Letters


  • Vol. 26, Iss. 23 — Dec. 1, 2001
  • pp: 1888–1890

Fabrication of ultralow-loss Si/SiO2 waveguides by roughness reduction

Kevin K. Lee, Desmond R. Lim, Lionel C. Kimerling, Jangho Shin, and Franco Cerrina  »View Author Affiliations

Optics Letters, Vol. 26, Issue 23, pp. 1888-1890 (2001)

View Full Text Article

Acrobat PDF (163 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



We demonstrate 0.8-dB/cm transmission loss for a single-mode, strip Si/SiO2 waveguide with submicrometer cross-sectional dimensions. We compare the conventional waveguide-fabrication method with two smoothing technologies that we have developed, oxidation smoothing and anisotropic etching. We observe significant reduction of sidewall roughness with our smoothing technologies, which directly results in reduced scattering losses. The rapid increase in the scattering losses as the waveguide dimension is miniaturized, as seen in conventionally fabricated waveguides, is effectively suppressed in the waveguides made with our smoothing technologies. In the oxidation smoothing case, the loss is reduced from 32 dB/cm for the conventional fabrication method to 0.8 dB/cm for the single-mode waveguide width of 0.5 µm . This is to our knowledge the smallest reported loss for a high-index-difference system such as a Si/SiO2 strip waveguide.

© 2001 Optical Society of America

OCIS Codes
(230.7370) Optical devices : Waveguides
(290.5880) Scattering : Scattering, rough surfaces

Kevin K. Lee, Desmond R. Lim, Lionel C. Kimerling, Jangho Shin, and Franco Cerrina, "Fabrication of ultralow-loss Si/SiO2 waveguides by roughness reduction," Opt. Lett. 26, 1888-1890 (2001)

Sort:  Author  |  Year  |  Journal  |  Reset


  1. J. Foresi, D. Lim, A. Agarwal, L. Kimerling, M. Tavassoli, M. Cox, M. Cao, W. Greene, “Small radius bends and large angle splitters in SOI waveguides,” Proc. SPIE 3007, 112–118 (1997).
  2. S. Suzuki, M. Yanagisawa, Y. Hibino, K. Oda, “High-density integrated planar lightwave circuits using SiO2– GeO2 waveguides with a high refractive index difference,” J. Lightwave Technol. 12, 790–796 (1994).
  3. A. Merlos, M. Acero, M. H. Bao, J. Bansells, J. Esteve, “TMAH/IPA anisotropic etching characteristics,” Sens. Actuators A 37–38, 737 (1993).
  4. T. Feuchter C. Thirstrup, “High precision planar waveguide propagation loss measurement technique using a Fabry–Perot cavity,” IEEE Photon. Technol. Lett. 6, 1244–1247 (1994).
  5. K. K. Lee, D. R. Lim, H.-C. Luan, A. Agrawal, J. Foresi, L. C. Kimerling, “Effect of size and roughness on light transmission in a Si/SiO2 waveguide: experiments and model,” Appl. Phys. Lett. 77, 1617–1619 (2000).
  6. O. Tabata, R. Asahi, H. Funabashi, K. Shimaoka, S. Sugiyama, “Anisotropic etching of silicon in TMAH solutions,” Sens. Actuators A 34, 51 (1992).
  7. S. Ghandhi, VLSI Fabrication Principles, Silicon and Gallium Arsenide (Wiley-Interscience, New York, 1994).
  8. D. Marcuse, “Mode conversion caused by surface imperfections of a dielectric slab waveguide,” Bell Syst. Tech. J. 48, 3187–3215 (1969).
  9. F. P. Payne J. P. R. Lacey, “A theoretical analysis of scattering loss from planar optical waveguides,” Opt. Quantum Electron. 26, 977–986 (1994).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited