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1 – 10 of over 1000The purpose of this paper is to provide an introduction to micro-electromechanical systems (MEMS) sensors and their commercialisation and to consider a number of recent…
Abstract
Purpose
The purpose of this paper is to provide an introduction to micro-electromechanical systems (MEMS) sensors and their commercialisation and to consider a number of recent applications, markets and product developments.
Design/methodology/approach
Following an introduction and a brief historical background to MEMS sensors and their commercialisation, the paper describes a selection of recent applications, with an emphasis on high volume uses. Various market figures are included to place these applications in a commercial context. Sensors for both physical variables and gases are considered.
Findings
The paper shows that MEMS sensor applications continue to grow in the automotive, consumer electronics and other industries, which consume many millions of sensors annually. New product developments reflect the requirement for smaller and lower-cost sensors with enhanced performance and greater functionality. Markets for physical sensors dominate but MEMS technology is making progressive inroads in the gas sensing field.
Originality/value
This article provides a timely review of a selection of recent MEMS sensor applications, markets and product developments.
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Keywords
This paper aims to provide details of MEMS (micro-electromechanical system) sensors produced from materials other than silicon.
Abstract
Purpose
This paper aims to provide details of MEMS (micro-electromechanical system) sensors produced from materials other than silicon.
Design/methodology/approach
Following a short introduction, this first considers reasons for using alternatives to silicon. It then discusses MEMS sensor products and research involving sapphire, quartz, silicon carbide and aluminium nitride. It then considers polymer and paper MEMS sensor developments and concludes with a brief discussion.
Findings
MEMS sensors based on the “hard” materials are well-suited to very-high-temperature- and precision-sensing applications. Some have been commercialised and there is a strong, on-going body of research. Polymer MEMS sensors are attracting great interest from the research community and have the potential to yield devices for both physical and molecular sensing that are inexpensive and simple to fabricate. The prospects for paper MEMS remain unclear but the technology may ultimately find uses in ultra-low-cost sensing of low-magnitude mechanical variables.
Originality/value
This provides a technical insight into the increasingly important role played by MEMS sensors fabricated from materials other than silicon.
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Yaser Javed, Mohtashim Mansoor and Irtiza Ali Shah
Pressure, being one of the key variables investigated in scientific and engineering research, requires critical and accurate measurement techniques. With the advancements in…
Abstract
Purpose
Pressure, being one of the key variables investigated in scientific and engineering research, requires critical and accurate measurement techniques. With the advancements in materials and machining technologies, there is a large leap in the measurement techniques including the development of micro electromechanical systems (MEMS) sensors. These sensors are one to two orders smaller in magnitude than traditional sensors and combine electrical and mechanical components that are fabricated using integrated circuit batch-processing technologies. MEMS are finding enormous applications in many industrial fields ranging from medical to automotive, communication to electronics, chemical to aviation and many more with a potential market of billions of dollars. MEMS pressure sensors are now widely used devices owing to their intrinsic properties of small size, light weight, low cost, ease of batch fabrication and integration with an electronic circuit. This paper aims to identify and analyze the common pressure sensing techniques and discuss their uses and advantages. As per our understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. The purpose of this study is to summarize the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimentalaerodynamics, micro-flow control and unmanned aerial vehicle (UAV)/micro aerial vehicle (MAV) applications.
Design/methodology/approach
The first part of the paper deals with an introduction to MEMS pressure sensors and mathematical relations for its fabrication. The second part covers pressure sensing principles followed by the application of MEMS pressure sensors in five major fields of aerospace industry.
Findings
In this paper, various pressure sensing principles in MEMS and applications of MEMS technology in the aerospace industry have been reviewed. Five application fields have been investigated including: Propulsion/Turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications. Applications of MEMS sensors in the aerospace industry are quite limited due to requirements of very high accuracy, high reliability and harsh environment survivability. However, the potential for growth of this technology is foreseen due to inherent features of MEMS sensors’ being light weight, low cost, ease of batch fabrication and capability of integration with electric circuits. All these advantages are very relevant to the aerospace industry. This work is an endeavor to present a comprehensive review of such MEMS pressure sensors, which are used in the aerospace industry and have been reported in recent literature.
Originality/value
As per the author’s understanding, usage of MEMS pressure sensors in the aerospace industry is quite limited due to cost constraints and indirect measurement approaches owing to the inability to locate sensors in harsh environments. Present work is a prime effort in summarizing the published literature for application of MEMS pressure sensors in the said field. Five broad application areas have been investigated including: propulsion/turbomachinery applications, turbulent flow diagnosis, experimental aerodynamics, micro-flow control and UAV/MAV applications.
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Junhui Zhang, Sai Zhang, Yuhua Yang and Wendong Zhang
Based on the micro-electro-mechanical system (MEMS) technology, acoustic emission sensors have gained popularity owing to their small size, consistency, affordability and easy…
Abstract
Purpose
Based on the micro-electro-mechanical system (MEMS) technology, acoustic emission sensors have gained popularity owing to their small size, consistency, affordability and easy integration. This study aims to provide direction for the advancement of MEMS acoustic emission sensors and predict their future potential for structural health detection of microprecision instruments.
Design/methodology/approach
This paper summarizes the recent research progress of three MEMS acoustic emission sensors, compares their individual strengths and weaknesses, analyzes their research focus and predicts their development trend in the future.
Findings
Piezoresistive, piezoelectric and capacitive MEMS acoustic emission sensors are the three main streams of MEMS acoustic emission sensors, which have their own advantages and disadvantages. The existing research has not been applied in practice, and MEMS acoustic emission sensor still needs further research in the aspects of wide frequency/high sensitivity, good robustness and integration with complementary metal oxide semiconductor. MEMS acoustic emission sensor has great development potential.
Originality/value
In this paper, the existing research achievements of MEMS acoustic emission sensors are described systematically, and the further development direction of MEMS acoustic emission sensors in the future research field is pointed out. It provides an important reference value for the actual weak acoustic emission signal detection in narrow structures.
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Sudarsana Jena and Ankur Gupta
Considering its vast utility in industries, this paper aims to present a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide…
Abstract
Purpose
Considering its vast utility in industries, this paper aims to present a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state-of-the-art gist to the researchers of the similar domain at one place.
Design/methodology/approach
Swiftly emerging research prospects in the micro-electro-mechanical system (MEMS) enable to build complex and sophisticated micro-structures on a substrate containing moving masses, cantilevers, flexures, levers, linkages, dampers, gears, detectors, actuators and many more on a single chip. One of the MEMS initial products that emerged into the micro-system technology is MEMS pressure sensor. Because of their high performance, low cost and compact in size, these sensors are extensively being adopted in numerous applications, namely, aerospace, automobile and bio-medical domain, etc. These application requirements drive and impose tremendous conditions on sensor design to overcome the tedious design and fabrication procedure before its reality. MEMS-based pressure sensors enable a wide range of pressure measurement as per the application requirements.
Findings
The paper provides a detailed review on fundamentals, classification and progresses in pressure sensors, along with its wide area of applications, its design aspects and challenges, to provide state of the art gist to the researchers of the similar domain at one place.
Originality/value
The present paper discusses the basics of MEMS pressure sensors, their working principles, different design aspects, classification, type of sensing diaphragm used and illustration of various transduction mechanisms. Moreover, this paper presents a comprehensive review on present trend of research on MEMS-based pressure sensors, its applications and the research gap observed till date along with the scope for future work, which has not been discussed in earlier reviews.
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To describe the historical development of micro‐electromechanical system (MEMS) sensor technology, to consider its current use in physical, gas and chemical sensing and to…
Abstract
Purpose
To describe the historical development of micro‐electromechanical system (MEMS) sensor technology, to consider its current use in physical, gas and chemical sensing and to identify and discuss future technological trends and directions.
Design/methodology/approach
This paper identifies the early research which led to the development of MEMS sensors. It considers subsequent applications of MEMS to physical, gas and chemical sensing and discusses recent technological innovations.
Findings
This paper illustrates the greatly differing impacts exerted on physical, gas and chemical sensing by MEMS technology. More recent developments are discussed which suggest strong market prospects for MEMS devices with analytical capabilities such as microspectrometers, micro‐GCs, microfluidics, lab‐on‐a‐chip and BioMEMS. This view is supported by various market data and forecasts.
Originality/value
This paper provides a technical and commercial insight into the applications of MEMS technology to physical and molecular sensors from the 1960s to the present day. It also identifies high growth areas for innovative developments in the technology.
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Zoheir Kordrostami, Kourosh Hassanli and Amir Akbarian
The purpose of this study is to find a new design that can increase the sensitivity of the sensor without sacrificing the linearity. A novel and very efficient method for…
Abstract
Purpose
The purpose of this study is to find a new design that can increase the sensitivity of the sensor without sacrificing the linearity. A novel and very efficient method for increasing the sensitivity of MEMS pressure sensor has been proposed for the first time. Rather than perforation, we propose patterned thinning of the diaphragm so that specific regions on it are thinner. This method allows the diaphragm to deflect more in response with regard to the pressure. The best excavation depth has been calculated and a pressure sensor with an optimal pattern for thinned regions has been designed. Compared to the perforated diaphragm with the same pattern, larger output voltage is achieved for the proposed sensor. Unlike the perforations that have to be near the edges of the diaphragm, it is possible for the thin regions to be placed around the center of the diaphragm. This significantly increases the sensitivity of the sensor. In our designation, we have reached a 60 per cent thinning (of the diaphragm area) while perforations larger than 40 per cent degrade the operation of the sensor. The proposed method is applicable to other MEMS sensors and actuators and improves their ultimate performance.
Design/methodology/approach
Instead of perforating the diaphragm, we propose a patterned thinning scheme which improves the sensor performance.
Findings
By using thinned regions on the diaphragm rather than perforations, the sensitivity of the sensor was improved. The simulation results show that the proposed design provides larger membrane deflections and higher output voltages compared to the pressure sensors with a normal or perforated diaphragm.
Originality/value
The proposed MEMS piezoelectric pressure sensor for the first time takes advantage of thinned diaphragm with optimum pattern of thinned regions, larger outputs and larger sensitivity compared with the simple or perforated diaphragm pressure sensors.
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A. Arshak, K. Arshak, G. Lyons, D. Waldron, D. Morris, O. Korostynska and E. Jafer
Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would…
Abstract
Purpose
Telemetry capsules have existed since the 1950s and were used to measure temperature, pH or pressure inside the gastrointestinal (GI) tract. It was hoped that these capsules would replace invasive techniques in the diagnosis of function disorders in the GI tract. However, problems such as signal loss and uncertainty of the pills position limited their use in a clinical setting. In this paper, a review of the capabilities of microelectromechanical systems (MEMS) for the fabrication of a wireless pressure sensor microsystem is presented.
Design/methodology/approach
The circuit requirements and methods of data transfer are examined. The available fabrication methods for MEMS sensors are also discussed and examples of wireless sensors are given. Finally, the drawbacks of using this technology are examined.
Findings
MEMS for use in wireless monitoring of pressure in the GI tract have been investigated. It has been shown that capacitive pressure sensors are particularly suitable for this purpose. Sensors fabricated for wireless continuous monitoring of pressure have been reviewed. Great progress, especially using surface micromachining, has been made in recent years. However, despite these advances, some challenges remain.
Originality/value
Provides a review of the capabilities of MEMS.
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Keywords
Shashi Kumar, Pradeep Kumar Rathore, Brishbhan Singh Panwar and Jamil Akhtar
This paper aims to describe the fabrication and characterization of current mirror-integrated microelectromechanical systems (MEMS)-based pressure sensor.
Abstract
Purpose
This paper aims to describe the fabrication and characterization of current mirror-integrated microelectromechanical systems (MEMS)-based pressure sensor.
Design/methodology/approach
The integrated pressure-sensing structure consists of three identical 100-µm long and 500-µm wide n-channel MOSFETs connected in a resistive loaded current mirror configuration. The input transistor of the mirror acts as a constant current source MOSFET and the output transistors are the stress sensing MOSFETs embedded near the fixed edge and at the center of a square silicon diaphragm to sense tensile and compressive stresses, respectively, developed under applied pressure. The current mirror circuit was fabricated using standard polysilicon gate complementary metal oxide semiconductor (CMOS) technology on the front side of the silicon wafer and the flexible pressure sensing square silicon diaphragm, with a length of 1,050 µm and width of 88 µm, was formed by bulk micromachining process using tetramethylammonium hydroxide solution on the backside of the wafer. The pressure is monitored by the acquisition of drain voltages of the pressure sensing MOSFETs placed near the fixed edge and at the center of the diaphragm.
Findings
The current mirror-integrated pressure sensor was successfully fabricated and tested using in-house developed pressure measurement system. The pressure sensitivity of the tested sensor was found to be approximately 0.3 mV/psi (or 44.6 mV/MPa) for pressure range of 0 to 100 psi. In addition, the pressure sensor was also simulated using Intellisuite MEMS Software and simulated pressure sensitivity of the sensor was found to be approximately 53.6 mV/MPa. The simulated and measured pressure sensitivities of the pressure sensor are in close agreement.
Originality/value
The work reported in this paper validates the use of MOSFETs connected in current mirror configuration for the measurement of tensile and compressive stresses developed in a silicon diaphragm under applied pressure. This current mirror readout circuitry integrated with MEMS pressure-sensing structure is new and fully compatible to standard CMOS processes and has a promising application in the development CMOS-MEMS-integrated smart sensors.
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This paper aims to illustrate how sensors can be fabricated by combining nanomaterials with micro-electromechanical system (MEMS) technology and to give examples of recently…
Abstract
Purpose
This paper aims to illustrate how sensors can be fabricated by combining nanomaterials with micro-electromechanical system (MEMS) technology and to give examples of recently developed devices arising from this approach.
Design/methodology/approach
Following a short introduction, this paper first identifies the benefits of MEMS technology. It then discusses the techniques for integrating carbon nanotubes with MEMS and provides examples of physical and molecular sensors produced by these methods. Combining other gas-responsive nanomaterials with MEMS is then considered and finally techniques for producing graphene on silicon devices are discussed. Brief concluding comments are drawn.
Findings
This shows that many physical and molecular sensors have been developed by combining nanomaterials with MEMS technology. These have been fabricated by a diverse range of techniques which are often complex and multi-stage, but significant progress has been made and some are compatible with standard CMOS processes, yielding fully integrated nanosensors.
Originality/value
This provides an insight into how two key technologies are being combined to yield families of advanced sensors.
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