D4.2 - On-chip Biosensing with high-Q Amorphous Silicon Microdisk Resonators
- Event
- AMA Conferences 2013
2013-05-14 - 2013-05-16
Nürnberg - Band
- Proceedings SENSOR 2013
- Chapter
- D4 - Biosensors I
- Author(s)
- T. Lipka, J. Amthor, H. Trieu, J. Müller - Hamburg University of Technology (Germany)
- Pages
- 535 - 539
- DOI
- 10.5162/sensor2013/D4.2
- ISBN
- 978-3-9813484-3-9
- Price
- free
Abstract
Low-loss hydrogenated amorphous silicon (a-Si:H) microdisk resonators which are employed as evanescent field refractive index sensors are presented. The resonances of the whispering gallery modes exhibit extinction ratios of >25dB and Q-factors ~10 4 in aqueous solutions. A sensitivity as high as >400nm/RIU was measured for NaCl-solved in DI-water. The resonators intrinsic limit of detection was calculated to be LOD=3.3x10 -4 and the minimum detectable amount of NaCl was experimentally determined to be 0.0375%. The measurements of the photonic evanescent field microdisk sensors prove that hydrogenated amorphous silicon photonic resonators can be exploited for label-free lab-onchip sensing applications.