title: Silicon based total internal reflection bio and chemical sensing with spectral phase detection.
abstract: Si-based total internal reflection (TIR) bio/chemical sensor presents an attractive alternative to Surface Plasmon Resonance (SPR) technology due to a relatively simple optical arrangement and technological implementation, as well as a relatively easy bio/chemical immobilization on Si/SiO(2) surface with a number of novel attractive applications. This sensor is based on the control of phase difference between p- and s-polarized components of light reflected from Si/air or Si/water interface in TIR geometry and a high sensitivity of the sensor is granted by a high refractive index of Si (3.56 at 1200 nm). We study properties of TIR sensors in a configuration of spectral phase detection and identify conditions of maximal phase sensitive response. We also experimentally show that the detection limit of Si-based TIR sensor can be lowered down to a level of detection of commercially available SPR devices (10(-6) Refractive Index Units, RIU) under the use of a proper low-noisy method of the phase control. The concept of Si-based TIR opens attractive prospects for the miniaturization of sensor devices, taking advantage of the advanced state of development of Si-based microfabrication technologies, while the proposed spectral phase detection scheme offers much easier packaging and calibration steps.
authors.affiliation: Engineering Physics Department, Ecole Polytechnique de Montréal, C. P. 6079, succ. Centre-Ville, Montréal, Québec, Canada.
authors.forename: Sergiy
authors.initials: S
authors.lastname: Patskovsky
authors.forename: In-Hyouk
authors.initials: IH
authors.lastname: Song
authors.forename: Michel
authors.initials: M
authors.lastname: Meunier
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Kabashin
mesh_terms: D000388:Air; D000465:Algorithms; D002138:Calibration; D004867:Equipment Design; D008027:Light; D015233:Models, Statistical; D008962:Models, Theoretical; D055095:Optics and Photonics; D057109:Scanning Laser Polarimetry / Q000379:methods; D012680:Sensitivity and Specificity; D012825:Silicon / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods*; D020349:Surface Plasmon Resonance; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D012822:Silicon Dioxide; D012825:Silicon