Title :
A capacitive pressure sensor with a novel multi-layered composite membrane structure fabricated by a three-mask process
Author :
Zhou, Min-Xin ; Huang, Qing-An ; Qin, Ming
Author_Institution :
Key Lab. of MEMS of Minist. of Educ., Southeast Univ., Nanjing, China
Abstract :
This paper presents a composite membrane structure for a capacitive pressure sensor, which was fabricated by a simple 3-mask process and sealed in vacuum by anodic bonding. The sensor utilizing combined SiO2/Si3N4 layers as the elastic dielectric layers exhibits a high sensitivity. Square membrane sensors with side lengths of 800 μm, 1000 μm, 1200 μm, and 1500 μm were fabricated, providing a measured sensitivity of 0.008pF/hPa, 0.012pF/hPa, 0.015pF/hPa and 0.02pF/hPa, respectively. Sensitivity enhancement of the sensor is qualitatively discussed based on the available physical effects of strained dielectrics, including electrostriction and flexoelectricity.
Keywords :
capacitive sensors; electrostriction; flexoelectricity; membranes; multilayers; pressure sensors; 1000 micron; 1200 micron; 1500 micron; 3-mask process; 800 micron; Si3N4; SiO2; anodic bonding; capacitive pressure sensor; electrostriction; flexoelectricity; multi-layered composite membrane; strained dielectrics; three-mask process; Biomembranes; Biosensors; Bonding; Capacitance; Capacitive sensors; Capacitors; Dielectric constant; Electrodes; Electrostriction; Solid state circuits;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems, 2005. Digest of Technical Papers. TRANSDUCERS '05. The 13th International Conference on
Print_ISBN :
0-7803-8994-8
DOI :
10.1109/SENSOR.2005.1496356
