Title :
Capacitive Pressure Sensor and Characterization as RF MEMS Device
Author :
Bolea, Raquel G. ; Luque, Antonio ; Quero, José Manuel
Author_Institution :
Univ. of Seville, Seville
Abstract :
In this paper, a MEMS capacitive pressure sensor, fabricated using a novel manufacturing process without the need of wafer bonding, is presented. The sensor is composed of a polysilicon membrane that deflects due to pressure difference applied over it. Two operation regions are observed: a non-linear sensitivity region at low pressure (0-30 kPa) and a linear one (30-200 kPa) in touch mode. A capacitance-to-frequency conversion circuitry is designed and validated to provide a sensitive sensing module. Experimental results show a sensitivity of 28.7 fF/kPa and of 13.93 Hz/kPa in the non-linear region. Finally, the microsensor is characterized as a RF MEMS tunable capacitor, in order to be used in radiofrequency applications, and parameters such as tuning ratio and quality factor are obtained. Among the most significant features of this device are versatility, high reliability, integrability, and high sensitivity.
Keywords :
capacitive sensors; capacitors; membranes; microsensors; pressure sensors; silicon; RF MEMS tunable capacitor; capacitance-to-frequency conversion circuitry; capacitive pressure sensor; manufacturing process; microsensor; polysilicon membrane; pressure 0 kPa to 30 kPa; pressure 30 kPa to 200 kPa; radiofrequency applications; sensitive sensing module; Biomembranes; Capacitance; Capacitive sensors; Circuits; Manufacturing processes; Micromechanical devices; Microsensors; Radiofrequency microelectromechanical systems; Sensor phenomena and characterization; Wafer bonding;
Conference_Titel :
Industrial Electronics, 2007. ISIE 2007. IEEE International Symposium on
Conference_Location :
Vigo
Print_ISBN :
978-1-4244-0754-5
Electronic_ISBN :
978-1-4244-0755-2
DOI :
10.1109/ISIE.2007.4375138
