Silicon photonic micro-disk resonators for label-free biosensing

Area of Science:

• Photonics
• Biotechnology
• Nanotechnology

Background:

• Silicon photonic biosensors are crucial for developing advanced Lab-on-Chip (LOC) systems.
• Multiplexed detection capabilities are essential for high-throughput biological sample analysis.

Purpose of the Study:

• To characterize the sensing performance of silicon photonic micro-disk resonators.
• To demonstrate their utility in detecting specific biomolecule capture for biosensing.
• To evaluate the potential for multiplexed interrogation of biological samples.

Main Methods:

• Characterization of 3 µm TE-mode and 10 µm dual TE/TM-mode silicon photonic micro-disk resonators.
• Experimental measurement of sensor sensitivities and quality factors for different modes.
• Serialization of multiple micro-disk resonators on a single waveguide bus using a CMOS-compatible process.

Main Results:

• Sensitivities of 26 nm/RIU (TE mode) and 142 nm/RIU (TM mode) were achieved.
• Quality factors of 3.3x10^4 (TE mode) and 1.6x10^4 (TM mode) were recorded.
• Demonstrated multiplexed interrogation of biological samples using serially arranged resonators.

Conclusions:

• Silicon photonic micro-disk resonators offer excellent sensing performance for biosensing.
• Dual TE/TM modes in larger resonators exhibit distinct sensing characteristics.
• The developed CMOS-compatible platform enables multiplexed biosensing for LOC systems.