A SiC MEMS Resonant Strain Sensor for Harsh Environment Applications

Author

Azevedo, Robert G. ; Jones, Debbie G. ; Jog, Anand V. ; Jamshidi, Babak ; Myers, David R. ; Chen, Li ; Fu, Xiao-An ; Mehregany, Mehran ; Wijesundara, Muthu B J ; Pisano, Albert P.

Author_Institution

Dept. of Mech. Eng., Univ. of California, Berkeley, CA

Volume

7

Issue

4

fYear

2007

fDate

4/1/2007 12:00:00 AM

Firstpage

568

Lastpage

576

Abstract

In this paper, we present a silicon carbide MEMS resonant strain sensor for harsh environment applications. The sensor is a balanced-mass double-ended tuning fork (BDETF) fabricated from 3C-SiC deposited on a silicon substrate. The SiC was etched in a plasma etch chamber using a silicon oxide mask, achieving a selectivity of 5:1 and etch rate of 2500 Aring/min. The device resonates at atmospheric pressure and operates from room temperature to above 300degC. The device was also subjected to 10 000 g shock (out-of-plane) without damage or shift in resonant frequency. The BDETF exhibits a strain sensitivity of 66 Hz/muepsiv and achieves a strain resolution of 0.11 muepsiv in a bandwidth from 10 to 20 kHz, comparable to state-of-the-art silicon sensors

Keywords

microsensors; plasma materials processing; silicon compounds; sputter etching; strain sensors; vibrations; wide band gap semiconductors; 10 to 20 kHz; MEMS resonant strain sensor; SiC-Si; atmospheric pressure; balanced-mass double-ended tuning fork; extensometer; harsh environment applications; plasma etch chamber; resonant frequency; silicon oxide mask; Atmospheric-pressure plasmas; Capacitive sensors; Etching; Micromechanical devices; Plasma applications; Plasma devices; Plasma temperature; Resonance; Silicon carbide; Vibrations; Carbide; MEMS; SiC; extensometer; gauge; harsh environment; resonator; silicon; strain;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2007.891997

Filename

4118144