Effect of Diaphragm Geometry and Piezoresistor Dimensions on the Sensitivity of a Piezoresistive Micropressure Sensor using Finite Element Analysis
K.Y.Madhavi1, M.Krishna2, C.S.Chandrashekhara Murthy3
1K.Y.Madhavi, Department of Physics, Maharani’s Science College for Women, Bangalore-560 001, India
2M. Krishna, Research and Development, Department of Mechanical Engineering, R V College of Engineering, Bangalore-560 059, India
3C.S Chandrashekhara Murthy, Research and Development, R V College of Engineering,Bangalore-560059, India
Manuscript received on July 11, 2013. | Revised Manuscript received on July 15, 2013. | Manuscript published on July 25, 2013. | PP: 35-40 | Volume-1 Issue-9, July 2013. | Retrieval Number: I0370071913/2013©BEIESP
Open Access | Ethics and Policies | Cite | Mendeley
© The Authors. Published By: Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Abstract: The performance of piezoresistive micropressure sensors based on their shape has been studied in this paper. Two sensors based on square and rectangular shaped diaphragms having the same surface area and thickness have been investigated. Performance parameters like the maximum induced stress, deflection and sensitivity of the diaphragms have been compared using the finite element tool ANSYS 10.0. An evaluation of the stress profile across both the diaphragms has been done. The role played by the dimensions of the piezoresistors in determining the performance of the sensor has been analyzed in detail using the computer aided design (CAD) tool Intellisuite. The analysis shows that the square diaphragm based sensor is more sensitive and has a higher gauge factor than the rectangular one but the stress profile of a rectangular based sensor is more suitable for making the placement of the piezoresistors less error prone. It has also been found that the variation in the length of the piezoresistor plays a greater role in determining the sensitivity of the sensor than width and thickness variations. From the results of the simulations the shape and design of the sensor can be optimized for a given pressure range.
Keywords: Diaphragm geometry, Finite element analysis, Micropressure sensors, Piezoresistance.