Modeling and design of a novel high-sensitivity electric field silicon-on-insulator sensor based on a whispering-gallery-mode resonator

In this paper, we present the modeling and design of a new approach to a miniaturized electric field sensor, based on a whispering-gallery-mode resonator coupled with a Fabry-Perot cavity in silicon-on-insulator technology. The sensing element consists of a metal oxide semiconductor capacitor, optimized to achieve high electrical sensitivity and low optical losses. The theoretical model of the whole sensor architecture includes the influence of all electrical and optical parameters, including thin oxide thickness, silicon and polysilicon doping concentration, optical losses due to propagation, absorption and scattering, wavelength and amplitude characteristics of the architecture, charge accumulation effects in the capacitor, and thermal effects. The very high sensitivity of this device, demonstrated by simulations, is due to the simultaneous influence of the two coupled resonators and the metal oxide semiconductor structure.