Abstract: Optical low-coherence interferometry (OLCI) takes advantage of the variation in refractive index in silicon-wire microring resonator (MRR) effective lengths to perform glucose biosensing using MRR interferograms. The MRR quality factor (Q), proportional to the effective length, could be improved using the silicon-wire propagation loss and coupling ratio from the MRR coupler. Our study showed that multimode interference (MMI) performed well in broad band response, but the splitting ratio drifted to 75/25 due to the stress issue. The glucose sensing sensitivity demonstrated 0.00279 meter per refractive-index-unit (RIU) with a Q factor of ~30,000 under transverse electric polarization. The 1,310 nm DFB laser was built in the OLCI system as the optical ruler achieving 655 nm characterization accuracy. The lowest sensing limitation was therefore 2 × 10−4 RIU. Moreover, the MRR effective length from the glucose sensitivity could be utilized to experimentally demonstrate the silicon wire effective refractive index with a width of 0.45 mm and height of 0.26 mm.
This is an open access article distributed under the
Creative Commons Attribution License which permits unrestricted use, distribution,
and reproduction in any medium, provided the original work is properly cited.
Export to BibTeX
MDPI and ACS Style
Hsu, S.-H.; Yang, Y.-C.; Su, Y.-H.; Wang, S.-M.; Huang, S.-A.; Lin, C.-Y. Biosensing Using Microring Resonator Interferograms. Sensors 2014, 14, 1184-1194.
Hsu S-H, Yang Y-C, Su Y-H, Wang S-M, Huang S-A, Lin C-Y. Biosensing Using Microring Resonator Interferograms. Sensors. 2014; 14(1):1184-1194.
Hsu, Shih-Hsiang; Yang, Yung-Chia; Su, Yu-Hou; Wang, Sheng-Min; Huang, Shih-An; Lin, Ching-Yu. 2014. "Biosensing Using Microring Resonator Interferograms." Sensors 14, no. 1: 1184-1194.