Thin film waveguide sensors for chemical detection

P. Ayras, D. F. Geraghty, S. Honkanen, K. M. Grace, B. Swanson, K. Shrouf, X. Yang, P. Katila, M. Leppihalme, A. Tervonen, N. Peyghambarian

Research output: Contribution to journalConference article


Chemical sensor scheme based on selective sensing surfaces and highly sensitive integrated optical transduction is presented. Self-assembly techniques are used to covalently attach species selective films onto the surface of silicon nitride waveguides. Exposure to targeted analytes results in selective absorption of these molecules onto the waveguide surface causing a change in the effective refractive index of the guided modes. These relative changes in effective refractive indices of TM and TE modes are using Zeeman interferometry. The measurements demonstrate reversible, real-time sensing of volatile organic compounds at ppm level. Improvements in the waveguide design are proposed to further increase the sensor performance.

Original languageEnglish (US)
Pages (from-to)310-316
Number of pages7
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - Jan 1 1999


ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

Ayras, P., Geraghty, D. F., Honkanen, S., Grace, K. M., Swanson, B., Shrouf, K., Yang, X., Katila, P., Leppihalme, M., Tervonen, A., & Peyghambarian, N. (1999). Thin film waveguide sensors for chemical detection. Proceedings of SPIE - The International Society for Optical Engineering, 3537, 310-316.