Optimization of Sensing Stators in Capacitive MEMS Operating at Resonance

Author

Frangi, Attilio ; Laghi, Giacomo ; Langfelder, Giacomo ; Minotti, Paolo ; Zerbini, Sarah

Author_Institution

Dept. of Civil & Environ. Eng, Politec. di Milano, Milan, Italy

Volume

24

Issue

4

fYear

2015

fDate

Aug. 2015

Firstpage

1077

Lastpage

1084

Abstract

This paper describes capacitive sensing stators for microelectromechanical systems (MEMS) suitably designed to minimize damping effects without worsening the capacitive variation per unit displacement. Such optimization can be exploited to maximize the readout signal in resonant systems. Two structures are designed with the aid of finite-element method models for the electrostatic domain, and with the aid of a deterministic integral model for damping predictions. The structures, fabricated in a 22-μm-thick surface micromachining process, demonstrate a 3× sensitivity improvement when used as resonant MEMS magnetometers.

Keywords

capacitive sensors; finite element analysis; magnetometers; micromechanical devices; optimisation; stators; capacitive MEMS; capacitive sensing stators; finite-element method models; microelectromechanical systems; resonant MEMS magnetometers; resonant systems; sensing stators optimization; size 22 mum; Capacitance; Damping; Micromechanical devices; Q-factor; Sensitivity; Sensors; Stators; Damping coefficient; MEMS sensors; capacitive readout; capacitive readout.; quality factor;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2014.2381515

Filename

7000521