Recent Progress of Miniature MEMS Pressure Sensors

Miniature Microelectromechanical Systems (MEMS) pressure sensors possess various merits, such as low power consumption, being lightweight, having a small volume, accurate measurement in a space-limited region, low cost, little influence on the objects being detected. Accurate blood pressure has been frequently required for medical diagnosis. Miniature pressure sensors could directly measure the blood pressure and fluctuation in blood vessels with an inner diameter from 200 to 1000 μm. Glaucoma is a group of eye diseases usually resulting from abnormal intraocular pressure. The implantable pressure sensor for real-time inspection would keep the disease from worsening; meanwhile, these small devices could alleviate the discomfort of patients. In addition to medical applications, miniature pressure sensors have also been used in the aerospace, industrial, and consumer electronics fields. To clearly illustrate the “miniature size”, this paper focuses on miniature pressure sensors with an overall size of less than 2 mm × 2 mm or a pressure sensitive diaphragm area of less than 1 mm × 1 mm. In this paper, firstly, the working principles of several types of pressure sensors are briefly introduced. Secondly, the miniaturization with the development of the semiconductor processing technology is discussed. Thirdly, the sizes, performances, manufacturing processes, structures, and materials of small pressure sensors used in the different fields are explained in detail, especially in the medical field. Fourthly, problems encountered in the miniaturization of miniature pressure sensors are analyzed and possible solutions proposed. Finally, the probable development directions of miniature pressure sensors in the future are discussed.

Download Full-text

Ferroelectric Thin Films in Micro-electromechanical Systems Applications

MRS Bulletin ◽

10.1557/s0883769400035934 ◽

1996 ◽

Vol 21 (7) ◽

pp. 59-65 ◽

Cited By ~ 218

Author(s):

D.L. Polla ◽

L.F. Francis

Keyword(s):

Thin Films ◽

Integrated Circuit ◽

Microelectromechanical Systems ◽

Pressure Sensors ◽

Ferroelectric Ceramic ◽

Consumer Electronics ◽

Ferroelectric Ceramics ◽

Control Electronics ◽

Commercial Applications ◽

And Control

Ferroelectric ceramic thin films fit naturally into the burgeoning field of microelectromechanical systems (MEMS). Microelectromechanical systems combine traditional Si integrated-circuit (IC) electronics with micromechanical sensing and actuating components. The term MEMS has become synonymous with many types of microfabricated devices such as accelerometers, infrared detectors, flow meters, pumps, motors, and mechanical components. These devices have lateral dimensions in the range of 10 μm–10 mm. The ultimate goal of MEMS is a self-contained system of interrelated sensing and actuating devices together with signal processing and control electronics on a common substrate, most often Si. Since fabrication involves methods common to the IC industry, MEMS can be mass-produced. Commercial applications for MEMS already span biomedical (e.g., blood-pressure sensors), manufacturing (e.g., microflow controllers), information processing (e.g., displays), and automotive (e.g., accelerometers) industries. More applications are projected in consumer electronics, manufacturing control, communications, and aerospace. Materials for MEMS include traditional microelectronic materials (e.g., Si, SiO2, Si3N4, polyimide, Pt, Al) as well as nontraditional ones (e.g., ferroelectric ceramics, shapememory alloys, chemical-sensing materials). The superior piezoelectric and pyroelectric properties of ferroelectric ceramics make them ideal materials for microactuators and microsensors.

Download Full-text

A pressure-deformation analytical model for rectangular diaphragm of MEMS pressure sensors

Modern Physics Letters B ◽

10.1142/s0217984917500464 ◽

2017 ◽

Vol 31 (05) ◽

pp. 1750046

Author(s):

Wu Zhou ◽

Dong Wang ◽

Huijun Yu ◽

Bei Peng

Keyword(s):

Pressure Sensor ◽

Applied Pressure ◽

Influence Factors ◽

Pressure Sensors ◽

Superposition Method ◽

Uniform Load ◽

Pressure Sensitive ◽

Partial Load ◽

Mems Pressure Sensors ◽

Measured Pressure

Rectangular diaphragm is commonly used as a pressure sensitive component in MEMS pressure sensors. Its deformation under applied pressure directly determines the performance of micro-devices, accurately acquiring the pressure–deflection relationship, therefore, plays a significant role in pressure sensor design. This paper analyzes the deflection of an isotropic rectangular diaphragm under combined effects of loads. The model is regarded as a clamped plate with full surface uniform load and partially uniform load applied on its opposite sides. The full surface uniform load stands for the external measured pressure. The partial load is used to approximate the opposite reaction of the silicon island which is planted on the diaphragm to amplify the deformation displacement, thus to improve the sensitivity of the pressure sensor. Superposition method is proposed to calculate the diaphragm deflections. This method considers separately the actions of loads applied on the simple supported plate and moments distributed on edges. Considering the boundary condition of all edges clamped, the moments are constructed to eliminate the boundary rotations caused by lateral load. The diaphragm’s deflection is computed by superposing deflections which produced by loads applied on the simple supported plate and moments distributed on edges. This method provides higher calculation accuracy than Galerkin variational method, and it is used to analyze the influence factors of the diaphragm’s deflection, includes aspect ratio, thickness and the applied force area of the diaphragm.

Download Full-text

Temperature measurement performance of silicon piezoresistive MEMS pressure sensors for industrial applications

Facta universitatis - series Electronics and Energetics ◽

10.2298/fuee1501123f ◽

2015 ◽

Vol 28 (1) ◽

pp. 123-131 ◽

Cited By ~ 5

Author(s):

Milos Frantlovic ◽

Ivana Jokic ◽

Zarko Lazic ◽

Branko Vukelic ◽

Marko Obradov ◽

...

Keyword(s):

Temperature Measurement ◽

Low Cost ◽

Pressure Sensors ◽

High Sensitivity ◽

Correction Method ◽

Industrial Applications ◽

Sensor Applications ◽

Piezoresistive Pressure Sensors ◽

Mems Pressure Sensors

Temperature and pressure are the most common parameters to be measured and monitored not only in industrial processes but in many other fields from vehicles and healthcare to household appliances. Silicon microelectromechanical (MEMS) piezoresistive pressure sensors are the first and the most successful MEMS sensors, offering high sensitivity, solid-state reliability and small dimensions at a low cost achieved by mass production. The inherent temperature dependence of the output signal of such sensors adversely affects their pressure measurement performance, necessitating the use of correction methods in a majority of cases. However, the same effect can be utilized for temperature measurement, thus enabling new sensor applications. In this paper we perform characterization of MEMS piezoresistive pressure sensors for temperature measurement, propose a sensor correction method, and demonstrate that the measurement error as low as ? 0.3?C can be achieved.

Download Full-text

Novel Pressure Sensors Made from Nanocomposites (Biodegradable Polymers–Metal Oxide Nanoparticles): Fabrication and Characterization

Ukrainian Journal of Physics ◽

10.15407/ujpe63.8.754 ◽

2018 ◽

Vol 63 (8) ◽

pp. 754 ◽

Cited By ~ 8

Author(s):

A. Hashim ◽

A. Hadi

Keyword(s):

Electrical Conductivity ◽

Dielectric Properties ◽

Low Cost ◽

Metal Oxide Nanoparticles ◽

Pressure Sensors ◽

High Sensitivity ◽

Oxide Nanoparticles ◽

Ac Electrical Conductivity ◽

Dc Electrical Conductivity ◽

Pressure Sensitive

This paper aims to the preparation of novel pressure-sensitive nanocomposites with low cost, light weight, and good sensitivity. The nanocomposites of polyvinyl alcohol, polyacrylic acid, and lead oxide nanoparticles have been investigated. The dielectric properties and dc electrical conductivity of (PVA–PAA–PbO2) nanocomposites have been studied. The dielectric properties of nanocomposites were measured in the frequency range (100 Hz–5 MHz). The experimental results showed that the dielectric constant and dielectric loss of (PVA–PAA–PbO2) nanocomposites decrease, as the frequency increases, and they increase with the concentrations of PbO2 nanoparticles. The ac electrical conductivity of (PVA–PAA–PbO2) nanocomposites increases with the frequency and the concentrations of PbO2 nanoparticles. The dc electrical conductivity of (PVA–PAA–PbO2) nanocomposites also increases with the concentrations of PbO2 nanoparticles. The application of pressure-sensitive nanocomposites has been examined in the pressure interval (60–200) bar. The results showed that the electrical resistance of (PVA–PAA–PbO2) pressure-sensitive nanocomposites decreases, as the compressive stress increases. The (PVA–PAA–PbO2) nanocomposites have high sensitivity to pressure.

Download Full-text

Humidity-Induced Voltage Shift on MEMS Pressure Sensors

Journal of Electronic Packaging ◽

10.1115/1.1615249 ◽

2003 ◽

Vol 125 (4) ◽

pp. 470-474 ◽

Cited By ~ 1

Author(s):

J. Albert Chiou ◽

Steven Chen ◽

Jinbao Jiao

Keyword(s):

Pressure Sensor ◽

Microelectromechanical Systems ◽

Pressure Sensors ◽

Anodic Bonding ◽

Absolute Pressure ◽

Stress Effect ◽

Induced Voltage ◽

Voltage Shift ◽

Mems Pressure Sensors ◽

Vacuum Cavity

The pressure sensor is one of the major applications of microelectromechanical systems (MEMS). An absolute pressure sensor utilizes anodic bonding to create a vacuum cavity between the silicon diaphragm and glass substrate. The manifold absolute pressure (MAP) sensing elements from a new supplier have exhibited negative voltage shifts after exposure to humidity. A hypothesis has been established that poor anodic bonding causes an angstrom-level gap between the silicon substrate and glass. Once moisture enters the gap in a vapor form and condenses as water droplets, surface tension can induce a piezoresistive stress effect that causes an unacceptable voltage shift. Finite element analyses were performed to simulate the phenomenon and the results correlated well with experimental observations.

Download Full-text

Development of a low-cost packaging for MEMS pressure sensors

2014 IEEE 9th IberoAmerican Congress on Sensors ◽

10.1109/ibersensor.2014.6995521 ◽

2014 ◽

Author(s):

Diego Conte Ayala Penalver ◽

Humber Furlan ◽

Mariana Amorim Fraga

Keyword(s):

Low Cost ◽

Pressure Sensors ◽

Mems Pressure Sensors

Download Full-text

Development and Characterization of Fiber-Based Pressure Sensors

Proceedings ◽

10.3390/proceedings2130746 ◽

2018 ◽

Vol 2 (13) ◽

pp. 746

Author(s):

Justus Landsiedel ◽

Tung Pham ◽

Thomas Bechtold

Keyword(s):

Low Cost ◽

Pressure Sensors ◽

The Body ◽

Capacitive Sensors ◽

Pressure Sensitive ◽

Promising Strategy ◽

Alternative Approaches ◽

Easy Integration ◽

Sensitive Variable

The integration of strand-based pressure sensors directly into woven textiles is a promising strategy to maintain textile properties, such as the flexibility, and to functionalize fabrics. The development of capacitive sensing elements is often based on the construction of laminates, which adversely affect the flexibility and thickness of textiles. In this paper, we present two alternative approaches by manufacturing cylindrical, pressure-sensitive, variable capacitors and twisted strand-based capacitive sensors. They lead to an easy integration method, where sensors can either be embedded or used to construct the body of textiles. In the cause of these studies, SBR/gelatin has been found to be a very useful pressure sensitive insulation system for the production of low cost capacitive sensors.

Download Full-text