Design And Analysis Of Silicon And Carbon based MEMS Piezoresistive Pressure Sensor

Abstract

Mobile and wearable pressure sensors are essential to ensure the efficiency of the health monitoring system such as rehabilitation and ergonomic application. Compared to traditional health monitoring, miniature size for low power consumption, flexibility, biocompatibility, rapidity, and low-cost sensors are among the essential parameters. Micro-Electro-Mechanical System (MEMS) pressure sensors offer very small size where it can respond rapidly to a very small changes in pressure. MEMS piezoresistive pressure sensor was chosen in this work because it capable of demonstrating a significant change in resistance that leads to better sensitivity of the sensor. Hence, the aim of this work is to investigate the effect of different material selection and structure of MEMS piezoresistive pressure sensors towards sensitivity, linearity error and change of resistance. To achieve this, finite element simulation was conducted to model and analyse the different types and materials of MEMS piezoresistive pressure sensors with a range of applied pressure. Diaphragm sensors using silicon or carbon as the piezoresistive material and different shapes were proposed in this work to evaluate the performance of piezoresistive pressure sensors. Simulation results show that MEMS piezoresistive pressure sensors using silicon with combinational Dash & E-shape have high sensitivity of 0.0870 mV/V?mmHg and good linearity, 99.9% as well as it is found that graphene as a group of carbon allotropes also shows better results with pressure sensitivity of 0.6458 mV/V?mmHg and 99% linearity by applying only 1 V biased voltage. Due to high material parameters like Young's modulus and Poisson ratio, has better sensitivity compared to silicon. A screen-printed piezoresistive pressure sensor was also presented in this work. Furthermore, this proposed piezoresistive pressure sensor has high performance to be implemented for various potential applications, including human-interactive electronics.