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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 27 — Dec. 19, 2011
  • pp: 26275–26282

Low-loss silicon slot waveguides and couplers fabricated with optical lithography and atomic layer deposition

A. Säynätjoki, L. Karvonen, T. Alasaarela, X. Tu, T. Y. Liow, M. Hiltunen, A. Tervonen, G. Q. Lo, and S. Honkanen  »View Author Affiliations

Optics Express, Vol. 19, Issue 27, pp. 26275-26282 (2011)

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We demonstrate low-loss silicon slot waveguides patterned with 248 nm deep-UV lithography and filled with atomic layer deposited aluminum oxide. Propagation losses less than 5 dB/cm are achieved with the waveguides. The devices are fabricated using low-temperature CMOS compatible processes. We also demonstrate simple, compact and efficient strip-to-slot waveguide couplers. With a coupler as short as 10 µm, coupling loss is less than 0.15 dB. The low-index and low-nonlinearity filling material allows nonlinearities nearly two orders of magnitude smaller than in silicon waveguides. Therefore, these waveguides are a good candidate for linear photonic devices on the silicon platform, and for distortion-free signal transmission channels between different parts of a silicon all-optical chip. The low-nonlinearity slot waveguides and robust couplers also facilitate a 50-fold local change of the waveguide nonlinearity within the chip by a simple mask design.

© 2011 OSA

OCIS Codes
(130.3130) Integrated optics : Integrated optics materials
(130.4310) Integrated optics : Nonlinear
(230.7370) Optical devices : Waveguides
(310.2785) Thin films : Guided wave applications
(220.4241) Optical design and fabrication : Nanostructure fabrication

ToC Category:
Integrated Optics

Original Manuscript: October 20, 2011
Revised Manuscript: November 25, 2011
Manuscript Accepted: November 26, 2011
Published: December 8, 2011

A. Säynätjoki, L. Karvonen, T. Alasaarela, X. Tu, T. Y. Liow, M. Hiltunen, A. Tervonen, G. Q. Lo, and S. Honkanen, "Low-loss silicon slot waveguides and couplers fabricated with optical lithography and atomic layer deposition," Opt. Express 19, 26275-26282 (2011)

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  1. H. Rong, A. Liu, R. Jones, O. Cohen, D. Hak, R. Nicolaescu, A. Fang, and M. Paniccia, “An all-silicon Raman laser,” Nature 433(7023), 292–294 (2005). [CrossRef] [PubMed]
  2. Y.-H. Kuo, H. Rong, V. Sih, S. Xu, M. Paniccia, and O. Cohen, “Demonstration of wavelength conversion at 40 Gb/s data rate in silicon waveguides,” Opt. Express 14(24), 11721–11726 (2006). [CrossRef] [PubMed]
  3. R. Salem, M. A. Foster, A. C. Turner, D. F. Geraghty, M. Lipson, and A. L. Gaeta, “All-optical regeneration on a silicon chip,” Opt. Express 15(12), 7802–7809 (2007). [CrossRef] [PubMed]
  4. Q. Xu and M. Lipson, “All-optical logic based on silicon micro-ring resonators,” Opt. Express 15(3), 924–929 (2007). [CrossRef] [PubMed]
  5. M. Hochberg and T. Baehr-Jones, “Towards fabless silicon photonics,” Nat. Photonics 4(8), 492–494 (2010). [CrossRef]
  6. Q. Xu, V. R. Almeida, R. R. Panepucci, and M. Lipson, “Experimental demonstration of guiding and confining light in nanometer-size low-refractive-index material,” Opt. Lett. 29(14), 1626–1628 (2004). [CrossRef] [PubMed]
  7. T. Baehr-Jones, B. Penkov, J. Huang, P. Sullivan, J. Davies, J. Takayesu, J. Luo, T.-D. Kim, L. Dalton, A. Jen, M. Hochberg, and A. Scherer, “Nonlinear polymer-clad silicon slot waveguide modulator with a half wave voltage of 0.25 V,” Appl. Phys. Lett. 92(16), 163303 (2008). [CrossRef]
  8. C. Koos, P. Vorreau, T. Vallaitis, P. Dumon, W. Bogaerts, R. Baets, B. Esembeson, I. Biaggio, T. Michinobu, F. Diederich, W. Freude, and J. Leuthold, “All-optical high-speed signal processing with silicon–organic hybrid slot waveguides,” Nat. Photonics 3(4), 216–219 (2009). [CrossRef]
  9. Y. Yue, L. Zhang, J. Wang, R. G. Beausoleil, and A. E. Willner, “Highly efficient nonlinearity reduction in silicon-on-insulator waveguides using vertical slots,” Opt. Express 18(21), 22061–22066 (2010). [CrossRef] [PubMed]
  10. T. Baehr-Jones, M. Hochberg, C. Walker, and A. Scherer, “High-Q optical resonators in silicon-on-insulator-based slot waveguides,” Appl. Phys. Lett. 86(8), 081101 (2005). [CrossRef]
  11. G. Wang, T. Baehr-Jones, M. Hochberg, and A. Scherer, “Design and fabrication of segmented, slotted waveguides for electro-optic modulation,” Appl. Phys. Lett. 91(14), 143109 (2007). [CrossRef]
  12. A. Spott, T. Baehr-Jones, R. Ding, Y. Liu, R. Bojko, T. O’Malley, A. Pomerene, C. Hill, W. Reinhardt, and M. Hochberg, “Photolithographically fabricated low-loss asymmetric silicon slot waveguides,” Opt. Express 19(11), 10950–10958 (2011). [CrossRef] [PubMed]
  13. Z. Wang, N. Zhu, Y. Tang, L. Wosinski, D. Dai, and S. He, “Ultracompact low-loss coupler between strip and slot waveguides,” Opt. Lett. 34(10), 1498–1500 (2009). [CrossRef] [PubMed]
  14. H. Sun, A. Chen, A. Szep, and L. R. Dalton, “Efficient fiber coupler for vertical silicon slot waveguides,” Opt. Express 17(25), 22571–22577 (2009). [CrossRef] [PubMed]
  15. T. Alasaarela, D. Korn, L. Alloatti, A. Säynätjoki, A. Tervonen, R. Palmer, J. Leuthold, W. Freude, and S. Honkanen, “Reduced propagation loss in silicon strip and slot waveguides coated by atomic layer deposition,” Opt. Express 19(12), 11529–11538 (2011). [CrossRef] [PubMed]
  16. A. Säynätjoki, T. Alasaarela, A. Khanna, L. Karvonen, P. Stenberg, M. Kuittinen, A. Tervonen, and S. Honkanen, “Angled sidewalls in silicon slot waveguides: conformal filling and mode properties,” Opt. Express 17(23), 21066–21076 (2009). [CrossRef] [PubMed]
  17. A. S. Sudbo, “Film mode matching: a versatile numerical method for vector mode field calculations in dielectric waveguides,” Pure Appl. Opt. 2(3), 211–233 (1993).
  18. J. Song, H. Zhao, Q. Fang, S. H. Tao, T. Y. Liow, M. B. Yu, G. Q. Lo, and D. L. Kwong, “Effective thermo-optical enhanced cross-ring resonator MZI interleavers on SOI,” Opt. Express 16(26), 21476–21482 (2008). [CrossRef] [PubMed]
  19. F. Grillot, L. Vivien, S. Laval, and E. Cassan, “Propagation loss in single-mode ultrasmall square silicon-on-insulator optical waveguides,” J. Lightwave Technol. 24(2), 891–896 (2006). [CrossRef]
  20. M. Gehl, R. Gibson, J. Hendrickson, A. Homyk, T. Alasaarela, A. Säynätjoki, A. Tervonen, S. Honkanen, S. Zandbergen, B. C. Richards, J. D. Olitzky, A. Scherer, G. Khitrova, H. M. Gibbs, J.-Y. Kim, and Y.-H. Lee, “Effect of atomic layer deposition on the quality factor of silicon nanobeam cavities,” presented at Fundamental Optical Processes in Semiconductors 2011, August 1–5, 2011, Lake Junaluska, NC, USA.

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