Diaphragm shape effect on the performance of foil-based capacitive pressure sensors

S M Khan,A M Hussain,M M Hussain,R B Mishra,N Qaiser

doi:10.1063/1.5128475

S M Khan, A M Hussain + Show 3 more

Open Access

https://doi.org/10.1063/1.5128475

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Abstract

We present detailed shape-based analyses to compare the performance of metal foil-based capacitive pressure sensors based on the shape of the diaphragm (top electrode). We perform a detailed analysis on the use of new material and deflection in various shaped diaphragms to act as a performance indicator for pressure-based capacitive sensors. A low-cost, recyclable, and readily available material is used to present an alternative to the expensive materials used in conventional pressure sensors. Diaphragms of five different shapes (circle, ellipse, pentagon, square, and rectangle) are fabricated and analyzed. Mathematical, FEM, and experimental tests are performed for capacitive sensors fabricated in five different shapes. The mathematically calculated deflection for each shaped diaphragm is compared with the results of the corresponding FEM simulations. Two different experiments are performed to verify the performance of pressure sensors.

Highlights

Pressure sensors are commonly used in biomedical, robotics, aerospace, automobile, and portable and consumer electronics applications
MEMS-based pressure sensors consist of a moveable mechanical element in the shape of a micrometer-sized diaphragm or a cantilever that deflects under the force of external pressure
Piezoresistive elements are used to detect diaphragm deflections to measure the absolute, gauge, and/or differential pressure. Such MEMS-based inertial devices are being used as commercial accelerometers, gyroscopes, and microphones that follow either the piezoresistive or capacitive sensing principle

Summary

Introduction

Pressure sensors are commonly used in biomedical, robotics, aerospace, automobile, and portable and consumer electronics applications.1–4 Among them, microelectromechanical system (MEMS) pressure sensors have found use in a diverse range of applications due to their compact size and superior performance. MEMS-based pressure sensors consist of a moveable mechanical element in the shape of a micrometer-sized diaphragm or a cantilever that deflects under the force of external pressure.

Results

Conclusion