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Published on: August 30, 2012
Refractive index sensor based on a 1D photonic crystal in a microfluidic channel
Pedro S Nunes1, Niels Asger Mortensen, Jörg P Kutter
1Department of Micro and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby, Denmark. pedro.nunes@nanotech.dtu.dk
Sensors (Basel, Switzerland)
|February 2, 2012
Summary
A novel silicon oxynitride refractive index sensor was developed using UV lithography. This photonic crystal sensor achieved a sensitivity of 836 nm/RIU for ethanol solutions, with potential for improved limit of detection.
Area of Science:
- Photonics
- Nanotechnology
- Materials Science
Background:
- Refractive index sensors are crucial for chemical and biological analysis.
- Silicon oxynitride offers advantageous optical and fabrication properties.
- Integrating photonic crystals with microfluidics enhances sensing capabilities.
Purpose of the Study:
- To fabricate and characterize a silicon oxynitride-based refractive index sensor.
- To evaluate the sensor's performance using ethanol solutions.
- To assess the potential for high-sensitivity refractive index measurements.
Main Methods:
- Fabrication of a 1D photonic crystal sensor in silicon oxynitride using UV lithography and dry etching.
- Integration of the photonic crystal with a microfluidic channel.
- Addressing the sensor with fiber-terminated planar waveguides.
- Experimental testing with ethanol solutions of varying concentrations.
Main Results:
- The sensor demonstrated a sensitivity of 836 nm/RIU for ethanol solutions.
- A limit of detection (LOD) of 6 × 10(-5) RIU was achieved.
- The achieved LOD is one order of magnitude higher than the theoretical limit.
Conclusions:
- The developed silicon oxynitride refractive index sensor shows promising performance.
- Further optimization is needed to approach the theoretical limit of detection.
- This sensor platform holds potential for advanced chemical sensing applications.
