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Design and Simulation of PolySi Diaphragm Capacitive Pressure Sensor

S. Sathyanarayanan, A. Vimala Juliet


This paper presents the design and simulation of a capacitive pressure sensor system for industrial and biomedical applications. Employing the Micro Electro Mechanical Systems (MEMS) technology, high sensor sensitivities and resolutions have been achieved. This report provides initial data on the design and simulation of such a sensor. The sensor is composed of a polysilicon diaphragm that deflects due to pressure applied over it. Applied pressure deflects the 2 µm diaphragm changing the capacitance between the Silicon substrate and the polysilicon diaphragm.  The pressure sensor provides a linear change in capacitance versus pressure in the range of 0.1MPa to 1MPa. The simulation result shows a displacement of 0.25µm / 0.1MPa of the diaphragm and capacitance of 30fF to 44fF in the linear region.


Capacitive pressure sensor, MEMS, PolySi, Sensor

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Ching-Liang Daia, Pin-Hsu Kaoa, Yao-Wei Taia, Chyan-Chyi Wub,” Micro FET pressure sensor manufactured using CMOS-MEMS technique,” Microelectronics Journal 39 (2008) pp.744–749.

Sathyanarayanan.S, Dr.A. Vimala Juliet, “Design of wireless pressure sensor for monitoring intraocular pressure” Proceeding of 2nd ISSS national Conference on MEMS, Microsensors, Smart materials, Structures and Systems”,2007, C36, pp. 28 – 29..

Th. G. S. M. Rijks, et al., "Microelectromechanical tunable capacitors for reconfigurable RF architectures," Journal of Micromechanics and Microengineering 16 (3), pp. 601-611, February 2006.

K.I. Arshak, D. Morris, A. Arshak, O. Korostynska, and E. Jafer, "Development of a wireless pressure measurement system using interdigitated capacitors," IEEE Sensors Journal, vol. 7, no. 1, January 2007.

Schnakenberg., C Kruger, J.G. Pfeffer, W. Mokwa, G.V. Bogel, R. Gunther, T.S. Rode, Intravascular pressure monitoring system, Sens. Actuators A 110 (2004) 61–67.

S-P. Chang and M.G. Allen, "Capacitive pressure sensors with stainless steel diaphragm and substrate" Journal of Micromechanics and Microengineering 14 (4), pp. 612-618, 2004.

S-P. Chang, and M.G. Allen, "Demonstration for integrating capacitive pressure sensors with read-out circuitry on stainless steel substrate, Sensors and Actuators, A. Physical , 116 (2), pp. 195-204, 2004.

Q. Huang and Michael Oberle, "A 0.5mW Passive Telemetry IC for Biomedical Applications," IEEE Joumal of Solid-State Circuits, Vol. 33, No. 7, July 1998.

Akar, T. Akin, and K. Najafi, "AWireless Batch Sealed Absolute Capacitive Pressure Sensor," Journal of Sensors and Actuators, pp. 29-38, 2001.

S. Chatzandroulis. D. Tsoukalas, and P.A. Neukomm, "A Miniature Pressure System with a Capacitive Sensor and a Passive Telemetry Link for Use in Implantable Applications," IEEE Journal of MEMS, Vol. 9, No. 1, March 2000.

B. Mezghani, S. Smaoui, M. Masmoudi, and C. Dufaza, "MEMS inductor in LC receivers for the RF link of cochlear implants," The 13th International C. on Microelectronics, Rabat, Morocco, Oct.2001.

L.Q. Du, G. Kwon, F. Arai, T. Fukuda, K. Itoigawa, Y. Tukahara, Sens. Actuator A 107 (2003) 7–13.

E. Defay, C. Millon, C. Malhaire, D. Barbier, Sens. Actuator A 99 (2002) 64–67.

P.-J. Chen, D. C. Rodger, M. S. Humayun, and Y.-C. Tai, "Unpowered Spiral-Tube Parylene Pressure Sensor for Intraocular Pressure Sensing," Sensors and Actuators A:Physical, vol. 127, 2006, pp. 276-282.

Sathyanarayanan.S, Dr. A. Vimala Juliet, “Design and Simulation of wireless passive pressure sensor for monitoring intraocular pressure” Proceeding of International Conference on Resource Utilization and Intelligent Systems”,2008, pp. 708 – 710.


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