OSA's Digital Library

Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 18, Iss. 24 — Nov. 22, 2010
  • pp: 25283–25291

Low-loss amorphous silicon wire waveguide for integrated photonics: effect of fabrication process and the thermal stability

Shiyang Zhu, G. Q. Lo, and D. L. Kwong  »View Author Affiliations

Optics Express, Vol. 18, Issue 24, pp. 25283-25291 (2010)

View Full Text Article

Enhanced HTML    Acrobat PDF (874 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Hydrogenated amorphous silicon (a-Si:H) wire waveguides were fabricated by plasma-enhanced chemical vapor deposition and anisotropic dry etching. With the optimized fabrication process, the propagation losses of as low as 3.2 ± 0.2 dB/cm for the TE mode and 2.3 ± 0.1 dB/cm for the TM mode were measured for the 200 nm (height) × 500 nm (width) wire waveguides at 1550 nm using the standard cutback method. The loss becomes larger at shorter wavelength (~4.4 dB/cm for TE and ~5.0 dB/cm for TM at 1520 nm) and smaller at longer wavelength (~1.9 dB/cm for TE and ~1.4 dB/cm for TM at 1620 nm). With the waveguide width shrinking from 500 nm to 300 nm, the TM mode loss keeps almost unchanged whereas the TE mode loss increases, indicating that the predominant loss contributor is the waveguide sidewall roughness, similar to the crystalline silicon waveguides. Although the a-Si:H and the upper cladding SiO2 were both deposited at 400°C, the propagation loss of the fabricated a-Si:H wire waveguides starts to increase upon furnace annealing under atmosphere at a temperature larger than 300°C: ~13–15 dB/cm after 400°C/30 min annealing and >70 dB/cm after 500°C/30 min annealing, which can be attributed to hydrogen out-diffusion. Even higher temperature (i.e., >600°C) annealing leads to the propagation loss approaching to the polycrystalline silicon counterparts (~40-50 dB/cm) due to onset of a-Si:H solid-phase crystallization.

© 2010 OSA

OCIS Codes
(130.3120) Integrated optics : Integrated optics devices
(230.3990) Optical devices : Micro-optical devices
(230.7370) Optical devices : Waveguides

ToC Category:
Integrated Optics

Original Manuscript: August 18, 2010
Revised Manuscript: September 30, 2010
Manuscript Accepted: October 8, 2010
Published: November 18, 2010

Shiyang Zhu, G. Q. Lo, and D. L. Kwong, "Low-loss amorphous silicon wire waveguide for integrated photonics: effect of fabrication process and the thermal stability," Opt. Express 18, 25283-25291 (2010)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. P. Koonath and B. Jalali, “Multilayer 3-D photonics in silicon,” Opt. Express 15(20), 12686–12691 (2007). [CrossRef] [PubMed]
  2. R. Sun, P. Dong, N. N. Feng, C. Y. Hong, J. Michel, M. Lipson, and L. Kimerling, “Horizontal single and multiple slot waveguides: optical transmission at λ = 1550 nm,” Opt. Express 15(26), 17967–17972 (2007). [CrossRef] [PubMed]
  3. B. Redding, S. Shi, and D. W. Prather, “Electromagnetic analysis of ring-cavity-assisted amplified spontaneous emission in Er:SiO2/a-Si horizontal slot waveguides,” IEEE J. Quantum Electron. 45(7), 825–829 (2009). [CrossRef]
  4. A. Martínez, J. Blasco, P. Sanchis, J. V. Galán, J. García-Rupérez, E. Jordana, P. Gautier, Y. Lebour, S. Hernández, R. Guider, N. Daldosso, B. Garrido, J. M. Fedeli, L. Pavesi, J. Martí, and R. Spano, “Ultrafast all-optical switching in a silicon-nanocrystal-based silicon slot waveguide at telecom wavelengths,” Nano Lett. 10(4), 1506–1511 (2010). [CrossRef] [PubMed]
  5. S. Y. Zhu, Q. Fang, M. B. Yu, G. Q. Lo, and D. L. Kwong, “Propagation losses in undoped and n-doped polycrystalline silicon wire waveguides,” Opt. Express 17(23), 20891–20899 (2009). [CrossRef] [PubMed]
  6. S. Y. Zhu, G. Q. Lo, J. D. Ye, and D. L. Kwong, “Influence of RTA and LTA on the optical propagation loss in polycrystalline silicon wire waveguides,” IEEE Photon. Technol. Lett. 22(7), 480–482 (2010). [CrossRef]
  7. K. Preston and M. Lipson, “Slot waveguides with polycrystalline silicon for electrical injection,” Opt. Express 17(3), 1527–1534 (2009). [CrossRef] [PubMed]
  8. K. Preston, S. Manipatruni, A. Gondarenko, C. B. Poitras, and M. Lipson, “Deposited silicon high-speed integrated electro-optic modulator,” Opt. Express 17(7), 5118–5124 (2009). [CrossRef] [PubMed]
  9. A. Harke, M. Krause, and J. Mueller, “Low-loss single mode amorphous silicon waveguides,” Electron. Lett. 41(25), 1377–1379 (2005). [CrossRef]
  10. S. K. Selvaraja, E. Sleeckx, M. Schaekers, W. Bogaerts, D. V. Thourhout, P. Dumon, and R. Baets, “Low-loss amorphous silicon-on-insulator technology for photonic integrated circuitry,” Opt. Commun. 282(9), 1767–1770 (2009). [CrossRef]
  11. R. Sun, K. McComber, J. Cheng, D. K. Sparacin, M. Beals, J. Michel, and L. C. Kimerling, “Transparent amorphous silicon channel waveguides with silicon nitride intercladding layer,” Appl. Phys. Lett. 94(14), 141108 (2009). [CrossRef]
  12. R. Sun, J. Cheng, J. Michel, and L. Kimerling, “Transparent amorphous silicon channel waveguides and high-Q resonators using a damascene process,” Opt. Lett. 34(15), 2378–2380 (2009). [CrossRef] [PubMed]
  13. Y. A. Vlasov and S. J. McNab, “Losses in single-mode silicon-on-insulator strip waveguides and bends,” Opt. Express 12(8), 1622–1631 (2004). [CrossRef] [PubMed]
  14. M. Gnan, S. Thoms, D. S. Macintyre, R. M. De La Rue, and M. Sorel, “Fabrication of low-loss photonic wires in silicon-on-insulator using hydrogen silsesquioxane electron-beam resist,” Electron. Lett. 44(2), 115–116 (2008). [CrossRef]
  15. J. Cardenas, C. B. Poitras, J. T. Robinson, K. Preston, L. Chen, and M. Lipson, “Low loss etchless silicon photonic waveguides,” Opt. Express 17(6), 4752–4757 (2009). [CrossRef] [PubMed]
  16. Y. Shoji, T. Ogasawara, T. Kamei, Y. Sakakibara, S. Suda, K. Kintaka, H. Kawashima, M. Okano, T. Hasama, H. Ishikawa, and M. Mori, “Ultrafast nonlinear effects in hydrogenated amorphous silicon wire waveguide,” Opt. Express 18(6), 5668–5673 (2010). [CrossRef] [PubMed]
  17. D. K. Sparacin, R. Sun, A. M. Agarwal, M. A. Beals, J. Michel, L. C. Kimerling, T. J. Conway, A. T. Pomerene, D. N. Carothers, M. J. Grove, D. M. Gill, M. S. Rasras, S. S. Patel, and A. E. White, “Low loss amorphous silicon channel waveguides for integrated photonics,” 3rd IEEE Intern. Conf. on Group IV Photonics, 255–257 (2006).
  18. T. Lipka, A. Harke, O. Horn, J. Amthor, and J. Muller, “Amorphous waveguides for high index photonic circuitry,” in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optical Society of America, 2009), paper OMJ2.
  19. M. Zeman, “Advanced amorphous silicon solar cell technologies,” in Thin Film Solar Cells Fabrication, Characterization and Applications, J. Poortmans and V. Arkhipov, eds., (John Wiley & Sons, 2006).
  20. P. K. Lim and W. K. Tam, “Local vibrational modes and the optical absorption tail of amorphous silicon,” Int. J. Mod. Phys. B 20(25 & 27), 4261–4266 (2006). [CrossRef]
  21. L. Liao, D. R. Lim, A. M. Agarwal, X. Duan, K. K. Lee, and L. C. Kimerling, “Optical transmission losses in polycrystalline silicon strip waveguides: effects of waveguide dimensions, thermal treatment, hydrogen passivation, and wavelength,” J. Electron. Mater. 29(12), 1380–1386 (2000). [CrossRef]

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.


Fig. 1 Fig. 2 Fig. 3
Fig. 4 Fig. 5

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited