Quantitative analysis of MEMS piezoresistive squared diaphragm pressure sensor for biomedical applications

Abstract

Now a days MEMS based for biomedical applications with high performance parameters like sensitivity and linearity are required for low pressure range.The low-pressure range (1–5 kPa) is a significant range that comprises intra-body pressures like intracranial pressure (ICP) and intraocular pressure (IOP).A lot of work on piezoresistive pressure sensor with different shapes diaphragms like squared, circular and rectangular has been carried out.In MEMS Piezoresistive Pressure sensors the most important pressure-sensitive component is the squared diaphragm. The performance of the Micro-sensor is directly determined, under uniform applied pressure with its deformation. In pressure sensor design, the accurate relationship between pressure and deformation plays a very consequence role. In this paper, squared diaphragm of silicon material is modeled and simulate using the analytical equations for a thin plate, along with the theory of small-deflection to providing quick insight regarding important parameter like stress and Deformation for the operating pressure range of 0 kPa–5 kPa. The mechanical behavior of micro-machined silicon diaphragm in terms of stress and deflection generation has been simulated.The piezoresistivity principle is used to assess the sensor's sensitivity. The mechanical change in the thin diaphragm in the form of deflection and stress is calculated and presented. In this Modeling both the analytical and simulated(FEA) results for the performance parameters such as stress, Deflection and the output voltage is computed and compared, it is found that the error between analytical and simulation results is no more than 5.6–6.5%.