Integrated photonics has become increasingly utilized for high-sensitivity measurements, owing in part to the active sensing principles it employs. In this work, we present the development and fabrication of a MEMS optomechanical microphone. The sensing waveguide consists of a photonic micro-ring resonator (MRR), where the optical resonance is determined by the optical path length difference (OPD) of the resonating structure. The waveguide is embedded within a SiOâ, diaphragm, and sound pressure deforms the diaphragm, altering the OPD, which in turn changes the optical resonance. This variation in resonance enables sound pressure detection. Additionally, an integrated thermal-optic phase tuner allows for the electrical tuning of the MRR's resonance by adjusting the OPD, thereby facilitating the implementation of control and detection algorithms. In this work, we present both optical and mechanical domain modeling of the device’s performance, including sensitivity, noise floor, and dynamic range. We also compare these models and provide a detailed analysis for the optimization of the figures of merit (FoM).
Meng et al. (Wed,) studied this question.