Silicon-based optoelectronic integrated circuit for label-free bio/chemical sensor
Kee, Jack Sheng
Park, Mi Kyoung
Date of Issue2013
School of Mechanical and Aerospace Engineering
We demonstrate a silicon-based optoelectronic integrated circuit (OEIC) for label-free bio/chemical sensing application. Such on-chip OEIC sensor system consists of optical grating couplers for vertical light coupling into silicon waveguides, a thermal-tunable microring as a tunable filter, an exposed microring as an optical label-free sensor, and a Ge photodetector for a direct electrical readout. Different from the conventional wavelength-scanning method, we adopt low-cost broadband ASE light source, together with the on-chip tunable filter to generate sliced light source. The effective refractive index change of the sensing microring induced by the sensing target is traced by scanning the supplied electrical power applied onto the tracing microring, and the detected electrical signal is read out by the Ge photodetector. For bulk refractive index sensing, we demonstrate using such OEIC sensing system with a sensitivity of ~15 mW/RIU and a detection limit of 3.9 μ-RIU, while for surface sensing of biotin-streptavidin, we obtain a surface mass sensitivity of Sm = ~192 µW/ng·mm−2 and a surface detection limit of 0.3 pg/mm2. The presented OEIC sensing system is suitable for point-of-care applications.
© 2013 OSA. This paper was published in Optics Express and is made available as an electronic reprint (preprint) with permission of OSA. The paper can be found at the following official DOI: [http://dx.doi.org/10.1364/OE.21.017931]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.