International Journal of Computer Applications |
Foundation of Computer Science (FCS), NY, USA |
Volume 70 - Number 3 |
Year of Publication: 2013 |
Authors: K.y.madhavi, M.krishna, C.s.chandrasekhara Murthy |
10.5120/11943-7745 |
K.y.madhavi, M.krishna, C.s.chandrasekhara Murthy . Design of a Piezoresistive Micropressure Sensor using Finite Element Analysis. International Journal of Computer Applications. 70, 3 ( May 2013), 20-26. DOI=10.5120/11943-7745
This paper is about designing a silicon based piezoresistive micro pressure sensor for greater sensitivity. Using Finite Element Analysis (FEA) the role played by important design parameters like the side length and the thickness of the pressure sensing membrane in determining the sensitivity of the sensor are studied in detail for a pressure of 100 kPa. The fracture stress of silicon is adopted as the main criterion for selecting the dimensions of the diaphragm in order to obtain maximum sensitivity and to ensure safe sensor operation. From the FEA results the side length and the thickness of the sensor are determined as 1000 µm and 17. 2 µm respectively. The stress profile of the diaphragm is studied in order to determine the optimum length and positioning of piezoresistors. The piezoresistors are placed in six different patterns and the sensitivity of the sensor for each pattern is determined. The maximum sensitivity is found to be 41. 6 mV/V/Bar. The effect of variation in the length of the piezoresistor on the sensitivity of the sensor has been studied and the optimum length of the piezoresistor is determined as 100 µm.