Performance Of Piezoresistive Pressure Sensor Research Articles

Formulation analysis and follow-up study of multi-turn configuration for performance enhancement of MEMS piezoresistive pressure sensor utilized for low-pressure measurement applications

PurposeThe purpose of this research is to study the performance of piezoresistive pressure sensors using polysilicon as the piezoresistive material, which is typically used to measure pressure in high-temperature environments.Design/methodology/approachThe performance of this sensor is enhanced by studying the influence of multi-turn configuration at which the piezoresistors are arranged. Different configurations are studied and compared by laying down their analytical solution.FindingsThe validation of analytical results is accomplished through finite element analysis using the software COMSOL Multiphysics. The best configuration, which uses a partial triple-turn configuration, was able to achieve a sensitivity of 116.00 mV/V/MPa over a simulated pressure range of 0 to 500 KPa.Originality/valueThe literature shows the study of single-turn and double-turn meander-shaped configuration of micro-electromechanical systems piezoresistive pressure sensor but multi-turn meander-shaped configuration using a square silicon diaphragm has not been reported. Its study has reflected promising results than its counterparts based on key performance parameters such as sensitivity and linearity and are more effective to be used for automotive, aviation, biomedical and consumer electronics applications.

Systematically Probing the Effect of Microscopic Features on the Sensing Performance of Piezoresistive Pressure Sensors

Systematically Probing the Effect of Microscopic Features on the Sensing Performance of Piezoresistive Pressure Sensors

Boosting Sensitivity and Durability of Pressure Sensors Based on Compressible Cu Sponges by Strengthening Adhesion of "Rigid-Soft" Interfaces.

The interface adhesion plays a key role between rigid metal and elastomer in compressible and stretchable conductors. However, the poor interfacial adhesion hinders their wide applications. To strengthen the interface adhesion, herein, a combination strategy of structure interlocking and polymer bridging is designed by introducing a method of subsurface-initiated atom transfer radical polymerization (sSI-ATRP). This method can make polymer brush root in polydimethylsiloxane (PDMS) subsurface, on this basis, metals further grow from subsurface to surface of PDMS via electroless deposition. As a result, the adhesive strength (≈2.5MPa) between metal layer and PDMS elastomer is 4 times higher than that made by common polymer modification. As a demonstration, pressure sensor is constructed by using as-prepared compressible 3D Cu sponge as a top electrode and paper-based interdigited metal electrode as a bottom electrode. The device sensitivity can reach up to 961.2kPa-1 and the durability can arrive at 3000 cycles without degradation. Thus, this proposed interface-enhancement strategy for rigid-soft materials can significantly promote the performance of piezoresistive pressure sensors based on 3D conductive sponge. In the future, it would also be expanded to the fabrication of stretchable conductors and extensively applied in other flexible and wearable electronics.

Design, Fabrication, and Dynamic Environmental Test of a Piezoresistive Pressure Sensor.

Microelectromechanical system (MEMS) pressure sensors have a wide range of applications based on the advantages of mature technology and easy integration. Among them, piezoresistive sensors have attracted great attention with the advantage of simple back-end processing circuits. However, less research has been reported on the performance of piezoresistive pressure sensors in dynamic environments, especially considering the vibrations and shocks frequently encountered during the application of the sensors. To address these issues, this paper proposes a design method for a MEMS piezoresistive pressure sensor, and the fabricated sensor is evaluated in a series of systematic dynamic environmental adaptability tests. After testing, the output sensitivity of the sensor chip was 9.21 mV∙bar−1, while the nonlinearity was 0.069% FSS. The sensor overreacts to rapidly changing pressure environments and can withstand acceleration shocks of up to 20× g. In addition, the sensor is capable of providing normal output over the vibration frequency range of 0–5000 Hz with a temperature coefficient sensitivity of −0.30% FSS °C−1 over the temperature range of 0–80 °C. Our proposed sensor can play a key role in applications with wide pressure ranges, high-frequency vibrations, and high acceleration shocks, as well as guide MEMS-based pressure sensors in high pressure ranges and complex environmental adaptability in their design.

Gamma Radiation Induced Effects on the Performance of Piezoresistive Pressure Sensors Fabricated Using Different Technologies

We have carried out experimental investigation of the effect of gamma radiation on the performance of piezoresistive pressure sensors realized using different fabrication processes. These processes included standard diffused piezoresistor process, silicon-on-insulator (SOI) wafer based process, and polysilicon piezoresistor based process. The pressure sensors were irradiated in a 60Co gamma chamber up to a total dose of 30 Mrad(Si). The sensors were characterized after different total dose exposures to measure the sensitivity, offset voltage, and hysteresis. All three types of sensors did not show failure up to the studied dose of 30 Mrad(Si). The sensors fabricated using diffused piezoresistor based and polysilicon piezoresistor based processes have shown insignificant change in the sensitivity. However, a significant change in the sensitivity (~13%) and offset voltage (~9%) was observed for the SOI wafer-based pressure sensor. The comparison of the gamma-induced degradation of three types of sensors shows that the polysilicon piezoresistor-based sensor has the best radiation hardness as it exhibits <1% degradation of the sensitivity, offset voltage, and hysteresis for gamma radiation exposure of 30 Mrad(Si).

Oven-controlled pressure sensor and its Mechanical aging

On the purpose of enhancing the performance of piezoresistive pressure sensor and reducing the difficulty of temperature compensation, the oven-controlled technology and mechanical aging method is studied in this paper. To be high efficiency and low consumption of oven-controlled method, the MEMS chip without package is used to reduce the thermal resistance. Furthermore, six-week mechanical aging was applied on the sensor. It is shown the mechanical aging can effectively improve the performance of pressure sensor. When the aginged sensor chip was tested at a range of -45°C to 50°C, the designed sensor can measure the atmospheric pressure as an error less than ±0.2hPa with just consuming 0.8mW power.

Effects of Temperature and Residual Stresses on the Output Characteristics of a Piezoresistive Pressure Sensor

The effects of temperature on the output performance of piezoresistive pressure sensors are studied in this paper. The influences of the environmental temperature, the residual stress due to the fabrication process, and the residual stress due to the packaging on the piezoresistive coefficient and resistance are theoretically investigated. The simulation results are obtained via finite element analysis through ANSYS. The results of experimental studies performed on piezoresistive pressure sensors fabricated using MEMS techniques are reported to verify the simulation results. The output characteristics of piezoresistive pressure sensors are shown to be substantially affected by not only the environmental temperature but also the residual stresses from the fabrication and packing processes.

Effect of Process Deviations on Performance of Piezoresistive Pressure Sensors

Diaphragm thickness and the corresponding piezoresistor locations change due to over or under etching in bulk micromachined piezoresistive pressure sensor which intern influences the device performance. In the present work, variation of sensitivity and nonlinearity of a micro electro mechanical system low pressure sensor is investigated. The sensor is modeled using finite element method to analyze the variation of sensitivity and nonlinearity with diaphragm thickness. To verify the simulated results, the sensors with different diaphragm thicknesses are fabricated. The models are verified by comparing the calculated results with experimental data. This study is potentially useful for the researchers as most of the times the diaphragm is either over-etched or under-etched due to inherent variation in wafer thickness and involving manual operations.

Design and Fabrication of an Improved MEMS-Based Piezoresistive Pressure Sensor

An improved piezoresistive pressure sensor is designed for harsh environment application. The highlight of this design is that the Wheatstone bridge circuit is put in lower surface of pressure diaphragm and sealed in the vacuum pressure cavity. The bridge circuit is led out by embedded Al electrodes on bonding surface. ANSYS software has been used to analyze the stress distribution of the diaphragm. By using the MEMS technology, the pressure sensor with the dimension of 1.5mm×1.5mm×500µm is fabricated. The performance of piezoresistive pressure sensor, including output, sensitivity, and nonlinearity, are investigated. The test results show that sensitivity is 20mV/V-MPa and maximum nonlinearity is 2.73%, which meet the requirements for the modern industry.

A piezoresistive GaAs pressure sensor with GaAs/AlGaAs membrane technology

This paper reports on the technology and performance of piezoresistive pressure sensors that utilize GaAs/AlGaAs membranes for pressure transduction into stress to induce resistance changes of p doped GaAs resistors. We have tested the sensor to differential pressure up to 8*104 Pa and in a temperature range of room temperature up to 433 K.