Investigation of Potting-Adhesive-Induced Thermal Stress in MEMS Pressure Sensor

Abstract

Thermal stress is one of the main sources of micro-electro-mechanical systems (MEMS) devices error. The Wheatstone bridge is the sensing structure of a typical piezoresistive MEMS pressure sensor. In this study, the thermal stress induced by potting adhesive in MEMS pressure sensor was investigated by experiments, calculated by analytics and analyzed by simulations. An experiment system was used to test the sensor at different air pressures and temperatures. The error becomes greater with the decrease in pressure. A set of novel formulas were proposed to calculate the stress–strain on Wheatstone bridge. The error increases with the temperature deviating from 25 °C. A full-scale geometric model was developed, and finite element simulations were performed, to analyze the effect of the stress on MEMS pressure sensor induced by different temperatures and thicknesses of potting adhesive. Simulation results agree well with the experiments, which indicated that there is a 3.48% to 6.50% output error in 0.35 mm potting adhesive at 150 °C. With the thickness of potting adhesive increasing, the variations of output error of the Wheatstone bridge present an N-shaped curve. The output error meets a maximum of 5.30% in the potting adhesive of 0.95 mm and can be reduced to 2.47%, by increasing the potting adhesive to 2.40 mm.

A Semi-Linear Elliptic Model for a Circular Membrane MEMS Device Considering the Effect of the Fringing Field

“…This because they provide an excellent approximation of the human–machine interface in all the cases wherein miniaturized-integrated electromechanical systems are required [ 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. Since the first batch device was produced in 1964 [ 22 ], the scientific and technological development in the field has strongly influenced the analysis and synthesis of physical-mathematical models that can describe the extremely complex underneath MEMS multi-physics [ 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. However, such theoretical models hardly provide analytical solutions.…”

Research on high temperature performance of pressure sensor

“…In recent years, with the development of Micro-Electro Mechanical System technology, silicon-based pressure sensors have been widely used in industrial production, humanmachine interactions and environmental monitoring due to the attractive advantages of simple structure, low cost and high precision [1][2][3][4][5][6][7][8][9]. In extreme temperature environments such as aerospace, automotive engines, oil exploration filed etc, * Author to whom any correspondence should be addressed.…”

Analysis of Thermal Characteristics of MEMS Sensors for Measuring the Rolling Period of Maritime Autonomous Surface Ships

“…In particular, the use of MEMS sensors in vehicles or machines is gradually increasing [14,15]. The importance of MEMS sensors is emphasized, and research on the thermal error of MEMS sensor is being actively conducted [16][17][18][19]. For example, research into the calibration suitable for the environment in which the sensor will be used.…”