Ring Resonator Photonic Sensing Device

Abstract

This thesis studies a micro ring resonator sensor structure built using the silicon-on-insulator (SOI) platform. The sensor detects changes in index of refraction with a sensitivity of 21 nm/RIU (RIU stands for refractive index unit), in close agreement to the predicted sensitivity, from computer simulations, of 24.4 nm/RIU. A study of thermal effects and residue layers was performed and a future sensor design capable of measuring layer thickness during evaporation is proposed. Background material relevant to the modelling of passive optical devices and a general overview of sensor design is presented. The sensitivity of various waveguide structures to changes in cover index of refraction are studied using computer simulations. The change in free spectral range (FSR) of the resonator sensor was characterized and was used to extend the active range of the device.