Small piezoresistive silicon microphones specially designed for the characterization of turbulent gas flows

Kälvesten, Edvard; Löfdahl, Lennart; Stemme, Göran

doi:10.1016/0924-4247(94)00880-q

Cited by 22 publications

(15 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Gad-el-Hak and Bandyopadhyay (1994) studied the Reynolds number effects on viscous boundary layers and concluded that to get effective results for turbulence measurements, the sensors need to be of the order of the viscous sublayer thickness, which is approximately 5 wall units. Kälvesten et al (1995) designed and fabricated piezoresistive transducers for turbulent gas flow measurements. They verified the ability of the transducer to measure the pressure eddies of 0.3-0.9 μ V/Pa in a turbulent boundary layer for different diaphragm sizes of 100 and 300 μ m. Acoustic sensors were used for turbulent gas flow measurement and its sensitivity relation with diaphragm side length was discussed.…”

Section: Aerospace Applicationsmentioning

confidence: 99%

A review of principles of MEMS pressure sensing with its aerospace applications

Javed

Mansoor

Shah

2019

View full text Add to dashboard Cite

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.

show abstract

Section: Aerospace Applicationsmentioning

confidence: 99%

A review of principles of MEMS pressure sensing with its aerospace applications

Javed

Mansoor

Shah

2019

View full text Add to dashboard Cite

show abstract

“…Another design with the same sensing mechanism as that of [54] has been proposed in [56] with a measured resonant frequency of 16 kHz. Piezoresistive microphones can be found in applications of fluidic mechanics [57,58] and aeroacoustics [52,59].…”

Section: Piezoresistive Microphonesmentioning

confidence: 99%

Design Approaches of MEMS Microphones for Enhanced Performance

Shah

Lee

et al. 2019

Journal of Sensors

View full text Add to dashboard Cite

This paper reports a review about microelectromechanical system (MEMS) microphones. The focus of this review is to identify the issues in MEMS microphone designs and thoroughly discuss the state-of-the-art solutions that have been presented by the researchers to improve performance. Considerable research work has been carried out in capacitive MEMS microphones, and this field has attracted the research community because these designs have high sensitivity, flat frequency response, and low noise level. A detailed overview of the omnidirectional microphones used in the applications of an audio frequency range has been presented. Since the microphone membrane is made of a thin film, it has residual stress that degrades the microphone performance. An in-depth detailed review of research articles containing solutions to relieve these stresses has been presented. The comparative analysis of fabrication processes of single- and dual-chip omnidirectional microphones, in which the membranes are made up of single-crystal silicon, polysilicon, and silicon nitride, has been done, and articles containing the improved performance in these two fabrication processes have been explained. This review will serve as a starting guide for new researchers in the field of capacitive MEMS microphones.

show abstract

“…where R is the resistance of each of the four resistors, G par is the longitudinal gauge factor, G per is the transverse gauge factor and the longitudinal strain of the resistor is assumed to dominate the contribution of the resistance change [18]. 6) and table 1.…”

Section: Theorymentioning

confidence: 99%

Media protected surface micromachined leverage beam pressure sensor

Melvås

Kälvesten

Stemme

2001

J. Micromech. Microeng.

Self Cite

View full text Add to dashboard Cite

In this paper we present the first surface micromachined ultraminiaturized, highly sensitive, pressure sensor that utilizes a force-transducing beam and a 2 µm thick polysilicon pressure sensing diaphragm as an encapsulation layer for high media isolation of the sensing piezoresistor. A beam is attached to the diaphragm at one end and to the cavity at the other end. The pressure-induced diaphragm deflection is transduced to strain in the beam and sensed by a piezoresistive strain-gauge on the beam. The piezoresistor is thus well isolated from the sensing environment. The pressure sensing performance was measured to 0.9 µV V −1 mmHg −1 .

show abstract

Small piezoresistive silicon microphones specially designed for the characterization of turbulent gas flows

Cited by 22 publications

References 12 publications

A review of principles of MEMS pressure sensing with its aerospace applications

A review of principles of MEMS pressure sensing with its aerospace applications

Design Approaches of MEMS Microphones for Enhanced Performance

Media protected surface micromachined leverage beam pressure sensor

Contact Info

Product

Resources

About