Abstract

This study proposes a microfabricated resonant pressure sensor based on electrostatic excitation and low-impedance piezoresistive detection in which a pair of double-ended tuning forks were utilized as resonators for differential outputs. In operations, targeted pressures deforms the pressure-sensitive membrane, resulting in stress variations of two resonators, leading to shifts of the intrinsic resonant frequencies, which were then measured piezoresistively. The developed microfabricated resonant pressure sensor was fabricated using simple SOI-MEMS processes and quantified in both open-loop and closed-loop manners, where the quality factor, differential sensitivity and linear correlation coefficient were quantified as higher than 10,000, 79.4 Hz/kPa and 0.99999, respectively. Compared to previous resonant piezoresistive sensors, the developed device leveraged single-crystal silicon as the piezoresistor, with advantages in simple sensing structures and fabrication steps. Furthermore, the differential setup was adopted in this study which can further improve the performances of the developed sensors.

Highlights

  • Resonant pressure micro-sensors are featured with quasi-digital outputs, which rely on electrostatic/electromagenetic/electrothermal excitations and capacitive and piezoresistive detections [1]

  • Previously reported resonant sensors based on electrostatic excitation and piezoresistive detection suffered from complicated structures and fabrication processes due to the limitations in the structure of the piezoresistor [3]

  • The piezoresistors are positioned at the end of the resonant beams to sense the buildup of the stress

Read more

Summary

Introduction

Resonant pressure micro-sensors are featured with quasi-digital outputs, which rely on electrostatic/electromagenetic/electrothermal excitations and capacitive and piezoresistive detections [1]. Previously reported resonant sensors based on electrostatic excitation and piezoresistive detection suffered from complicated structures and fabrication processes due to the limitations in the structure of the piezoresistor [3]. In order to address this issue, in this study, the resonators of the proposed pressure micro-sensor were electrostatically driven into oscillation and sensed by low-impedance piezoresistive detection where single-crystal silicon was used as the piezoresistor, which is featured with low DC biased voltages, simple sensing structures (see Figure 1) and fabrication steps.

Device Design and Fabrication
Device Characterization
Findings
Conclusions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.