Simulation and Parametrical Analysis of Highly Sensitive MEMS Based Piezoresistive Pressure Sensor
Kakali Das, Sunipa Roy
Department of Electronics and Communication Engineering, St. Thomas College of Engineering and Technology, Kolkata, India
Department of Electronics and Communication Engineering, Guru Nanak Institute of Technology, Kolkata, India
In this paper, a parametric analytical and simulation solution for highly sensitive MEMS based piezoresistive pressure sensor is proposed. The system output sensitivity of the pressure sensor is evaluated by interpreting the proper selection of diaphragm geometry of the square diaphragm and the position of piezoresistors. In order to achieve better sensor performance, the results of diaphragm deflection, stress profile and other effects are parametrically analyzed with the simulation using MATLAB programming. The range of applied pressure is considered from 5.333kPa (minmum value) to 39.997 kPa (maximum value). Blood pressure of human body should normally be less than 120/80 mm Hg (less than 120 systolic and less than 80 diastolic) for an adult age 20 or over. The sensor simulates the results for diaphragm deflection and induced stress for maximum and minimum measurable equivalent blood pressure of human body. Sensitivity of the sensor is influenced more powerfully by diaphragm thickness. Out of various diaphragm geometries, for a particular square silicon <100> diaphragm, the maximum deflection of 0.14 μm is found for an applied pressure of 39.997 kPa and the maximum stress of 25 MPa is achieved for the same applied pressure.
MEMS; piezoresistor; pressure sensor; diaphragm; MATLAB