Piezoresistive Pressure Sensor Design, Simulation and Modification Using CoventorWare Software

In this study the properties of a modified MEMS Piezoresistive (PZR) Pressure Sensor device is investigated. The Wheatstone bridge circuit configuration is used to arrange the implanted piezoresistors to measure small resistance change. In the methodology of the study CoventorWare simulation software is used to design and simulate the existing pressure sensor. Modification to improve the pressure sensor’s output was then made to the design. The modification made involved the incorporation of additional resistors in parallel with the existing resistors forming the Wheatstone bridge making them eight implanted resistors in all instead of four. Results showed that the modified sensor gives a lower output voltage when the x and y edge offsets are varied with a maximum output voltage of 96 mV compare to the typical sensor maximum output voltage of 185 mV. It also has a wider dynamic range from 0 to 9.5 MPa for pressure measurement as compared to the typical sensor which has a range from 0 to 4.0 MPa.