Micro-opto-mechanical pressure sensor via ring resonator-based Mach-Zehnder interferometer

A microscale opto-mechanical pressure sensors was studied using a combination design of silicon microring resonator and Mach-Zehnder interferometer placed on the middle of the pliable squared diaphragm fabricated from silicon-polydimethylsiloxane layers. The outward displacement and deflection of the diaphragm in z-directions along the x- and y-axes were calculated using the finite element method. The optical transfer function of proposed layout was derived using the delay line signal approach. The optimum geometrical parameters of the system and a critical coupling condition were determined for pressure sensing application and an extended quasi-FSR as large as 108 nm with quality factor of 4752 was realized. The performance of the sensor in the range of 0-225 kpa was studied based on the spectral shift of output resonance peaks due to the applied shear stress on the diaphragm. The sensitivity and a minimum detectable pressure of proposed is calculated to be 0.38 nm/kPa and 50 pa, respectively. The proposed pressure sensor fulfills the expectations of microscale size, high precision, and high sensitivity, and this sensor potentially can be used as high-performance devices in the precision Instrumentation, aircrafts technology as well as harsh environments.

Automated summary

In this study, a microscale opto-mechanical pressure sensor was successfully investigated using a combination design of silicon microring resonator and Mach-Zehnder interferometer. The sensor exhibited microscale size, high precision, and high sensitivity, and demonstrated promising performance in pressure sensing applications.