Dynamic modelling and analysis of MEMS-based low-pressure range capacitive sensors for biomedical applications

Abstract

Sensitivity and linearity are promising parameters for MEMS (Microelectromechanical system) based Capacitive pressure sensors (CPS). This study discusses the basic principle, classification of the sensing mechanism and recent trends for improving the sensitivity. The review includes mathematical analysis and dynamic modelling on various parameters like deflection, and capacitance. In addition, this comprehensive study also discusses capacitive pressure sensors of different structures/shapes with their advantages and limitations. MEMS-based Capacitive pressure sensors have attracted research interest in recent years for various potential applications in the field of biological, industrial, microphones, touch screens etc. This article deals with different substrates and membrane materials for the sensor along with fabrication methodology. Existing technologies for MEMS-based Capacitive pressure sensor faces common challenges which are discussed here. Advancements in MEMS sensing technology and attractive feature of state of the art in MEMS-based low-range capacitive pressure sensors make use of it in medical applications like BP, IOP and ICP are discussed in detail. Finally, the main finding of this study shows the square shape CPS gives maximum deflection up to the range of 10 kPa.