Grating-based evanescent field molecular sensor using a thin silicon waveguide layer

US8796012B2 · kind B2 · utility

Assignee

• National Research Council of Canada · CA

Inventors

• Bill Sinclair · Manotick, CA
• Jens Schmid · Ottawa, CA
• Philip Waldron · Whitby, CA
• Dan Xu · Vernon Hills, US
• Adam Densmore · Victoria, CA
• Trevor Mischki · Ottawa, CA
• Greg Lopinski · Ottawa, CA
• Jean Lapointe · Ottawa, CA
• Daniel Poitras · Ottawa, CA
• Siegfried Janz · Ottawa, CA

Key dates

• Filing date: Dec 2, 2009
• Grant date: Aug 5, 2014
• Expiry date: Mar 11, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S436/805
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A technique for high sensitivity evanescent field molecular sensing employs a detection scheme that simultaneously couples a polarized beam to a single mode of a waveguide, and couples the polarized beam out of the waveguide to specularly reflect the beam by the same grating. Strong interaction with the single (preferably TM) mode is provided by using a silicon on insulator (SOI) wafer having a waveguide thickness chosen between 10-400 nm so that the majority of the mode field strength spans the evanescent field. Well known, robust techniques for producing a grating on the waveguide are provided. Interrogation from a backside of the SOI wafer is taught.