Piezoresistive pressure sensors are one of the very first products of MEMS technology, and are used in various
fields like automotive industries, aerospace, biomedical applications, and household appliances. Amongst
various transduction principles of pressure sensor piezoresistive transduction mechanism is widely used. Over a
decade therehas been tremendous improvement in the development of the design of piezoresistive pressure
sensor starting with the invention of piezoresistance in the silicon to the recent piezoresistive pressure sensor
materials. Because of its high sensitivity, high gauge factor, independent to the temperature, linear operation
over a wide range of pressure, and many more advantages. This paper provides survey of piezoresistive pressure
sensor including their pressure sensing mechanism, evolution, materials, design considerations, performance
parameter that to be considered and the fabrication process used
Microelectromechanical Systems (MEMS) are miniature devices comprising of integrated mechanical (levers, springs, deformable membranes, vibrating structures, etc.) and electrical (resistors, capacitors, inductors, etc.) components designed to work in concert to sense and report on the physical properties of their immediate or local environment, or, when signaled to do so, to perform some kind of controlled physical interaction or actuation with their immediate or local environment
Microelectromechanical Systems (MEMS) are miniature devices comprising of integrated mechanical (levers, springs, deformable membranes, vibrating structures, etc.) and electrical (resistors, capacitors, inductors, etc.) components designed to work in concert to sense and report on the physical properties of their immediate or local environment, or, when signaled to do so, to perform some kind of controlled physical interaction or actuation with their immediate or local environment
MEMS = Micro Electro Mechanical System
Any engineering system that performs electrical (switching ,deciding) and mechanical functions (sensing,moving,heating) with components in micrometers is a MEMS.
Piezoresistive pressure sensors are one of the very-first products of MEMS technology. Those products are widely used in biomedical applications, automotive industry and household appliances.
The sensing material in a piezoresistive pressure sensor is a diaphragm formed on a silicon substrate, which bends with applied pressure. A deformation occurs in the crystal lattice of the diaphragm because of that bending. This deformation causes a change in the band structure of the piezoresistors that are placed on the diaphragm, leading to a change in the resistivity of the material. This change can be an increase or a decrease according to the orientation of the resistors.
The Piezoelectric transducer is an electroacoustic transducer use for conversion of pressure or mechanical stress into an alternating electrical force. It is used for measuring the physical quantity like force, pressure, stress, etc., which is directly not possible to measure.The piezo transducer converts the physical quantity into an electrical voltage which is easily measured by analogue and digital meter.
The piezoelectric transducer uses the piezoelectric material which has a special property, i.e. the material induces voltage when the pressure or stress applied to it. The material which shows such property is known as the electro-resistive element
Physicochemical Properties and Proposed Mechanism in the Obtainment of 4-Hidr...IJERA Editor
The mechanism for the poly-condensation event of conjugated polymers with ending 4-hydroxycoumarin has
been proposed. It happened under H2SO4 acidic conditions only using enolic-coumarins without any substituent
at third position. It was studied using Matrix assisted laser desorption/ionization time-of-flight (MALDI-Tof)
mass spectrometry. Besides, some physicochemical properties were analyzed using Thermo-gravimetric (TGA),
X-ray and UV-Vis analysis
Comparison of Cell formation techniques in Cellular manufacturing using three...IJERA Editor
In the present era of globalization and competitive market, cellular manufacturing has become a vital tool for
meeting the challenges of improving productivity, which is the way to sustain growth. Getting best results of
cellular manufacturing depends on the formation of the machine cells and part families. This paper examines
advantages of ART method of cell formation over array based clustering algorithms, namely ROC-2 and DCA.
The comparison and evaluation of the cell formation methods has been carried out in the study. The most
appropriate approach is selected and used to form the cellular manufacturing system. The comparison and
evaluation is done on the basis of performance measure as grouping efficiency and improvements over the
existing cellular manufacturing system is presented.
MEMS = Micro Electro Mechanical System
Any engineering system that performs electrical (switching ,deciding) and mechanical functions (sensing,moving,heating) with components in micrometers is a MEMS.
Piezoresistive pressure sensors are one of the very-first products of MEMS technology. Those products are widely used in biomedical applications, automotive industry and household appliances.
The sensing material in a piezoresistive pressure sensor is a diaphragm formed on a silicon substrate, which bends with applied pressure. A deformation occurs in the crystal lattice of the diaphragm because of that bending. This deformation causes a change in the band structure of the piezoresistors that are placed on the diaphragm, leading to a change in the resistivity of the material. This change can be an increase or a decrease according to the orientation of the resistors.
The Piezoelectric transducer is an electroacoustic transducer use for conversion of pressure or mechanical stress into an alternating electrical force. It is used for measuring the physical quantity like force, pressure, stress, etc., which is directly not possible to measure.The piezo transducer converts the physical quantity into an electrical voltage which is easily measured by analogue and digital meter.
The piezoelectric transducer uses the piezoelectric material which has a special property, i.e. the material induces voltage when the pressure or stress applied to it. The material which shows such property is known as the electro-resistive element
Physicochemical Properties and Proposed Mechanism in the Obtainment of 4-Hidr...IJERA Editor
The mechanism for the poly-condensation event of conjugated polymers with ending 4-hydroxycoumarin has
been proposed. It happened under H2SO4 acidic conditions only using enolic-coumarins without any substituent
at third position. It was studied using Matrix assisted laser desorption/ionization time-of-flight (MALDI-Tof)
mass spectrometry. Besides, some physicochemical properties were analyzed using Thermo-gravimetric (TGA),
X-ray and UV-Vis analysis
Comparison of Cell formation techniques in Cellular manufacturing using three...IJERA Editor
In the present era of globalization and competitive market, cellular manufacturing has become a vital tool for
meeting the challenges of improving productivity, which is the way to sustain growth. Getting best results of
cellular manufacturing depends on the formation of the machine cells and part families. This paper examines
advantages of ART method of cell formation over array based clustering algorithms, namely ROC-2 and DCA.
The comparison and evaluation of the cell formation methods has been carried out in the study. The most
appropriate approach is selected and used to form the cellular manufacturing system. The comparison and
evaluation is done on the basis of performance measure as grouping efficiency and improvements over the
existing cellular manufacturing system is presented.
Cyclic Life Establishment of First Stage Compressor Blade - Aircraft Jet EngineIJERA Editor
In this project an attempt is made to identify the cyclic life, modal efficacies for assessing the life that is declared
by the Original Engine Manufacturer. Using the Goodman diagram and knowing the mean stress of the blade for
all rpm conditions.
New Technique Using Multiple Symmetric keys for Multilevel EncryptionIJERA Editor
In a world of accelerating communications, cryptography has become an essential component of the modern
means of communication systems. The emergence of the webas a reliable medium for commerce and
communication has made cryptography an essential component. Many algorithms or ciphers are in use
nowadays. The quality of the cipher is judged byits ability to prevent an unrelated party fromknowingthe
original content of the encrypted message. The proposed “Multilevel Encryption Model” is a cryptosystem that
adopts the basic principles of cryptography. It uses five symmetric keys (multiple)
in floating point numbers, plaintext, substitution techniques and key combinations with unintelligible
sequence to produce the ciphertext. The decryption process is also designed to reproduce the plaintext
Benefits of the use of thermal insulation in a naturally ventilated residenti...IJERA Editor
The use of thermal insulation is not a common practice in civil construction in Brazil. The national standard for
thermal performance and the energy efficiency labeling program do not require the use of thermal insulation in
the building envelope, even for the hottest and for the coldest regions of the country. Brazil has a temperate
climate region that covers 7.2% of its territory and contains important and populous cities. This paper explores
the benefits of the use of thermal insulation in dwellings located in that climate. A heat balance analysis was
conducted in the computational model of a naturally ventilated single-family residential building. The simulation
task was carried out in the EnergyPlus software with the use of weather files of three cities, classified as
temperate climates. The main sources of heat transfer through the building envelope were identified and
subjected to a sensitivity analysis, seeking for the building performance optimization. Simulation results shows
that thermal insulation can be applied on building walls, roof and floor, with benefits measured as a reduction in
the heating degree hours along the year. Increase in cooling degree hours during the summer could be overcome
with strategies to control the solar heat gain on windows
Power System Stability Enhancement Using FLC and MPC for STATCOMIJERA Editor
In modern power system, Static Compensator (STATCOM) is used to alleviate the transient stability problem
and damping power system oscillations. In this paper different STATCOM control scheme using fuzzy logic
controller (FLC) and model predictive controller (MPC) for the Single Machine Infinite Bus (SMIB) system in
improving transient stability is simulated using MATLAB/ Simulink in power systems block set. PI, FLC and
MPC signals are used to control and exchange the required reactive power among the STATCOM and the power
grid. A load disturbance is simulated and the behavior of the system for voltage fluctuations has been studied.
Simulation results using Proportional-Integral (PI) controller, Fuzzy Logic Controller (FLC) and Model
Predictive Controller (MPC) have been compared. The effectiveness of the different controllers in damping
oscillations and improving power system stability has been discussed.
Adaptive Fuzzy-Neural Control Utilizing Sliding Mode Based Learning Algorithm...IJERA Editor
This paper introduces an adaptive fuzzy-neural control (AFNC) utilizing sliding mode-based learning algorithm
(SMBLA) for robot manipulator to track the desired trajectory. A traditional sliding mode controller is applied to
ensure the asymptotic stability of the system, and the fuzzy rule-based wavelet neural networks (FWNNs) are
employed as the feedback controllers. Additionally, a novel adaptation of the FWNNs parameters is derived
from the SMBLA in the Lyapunov stability theorem. Hence, the AFNC approximates parameter variation,
unmodeled dynamics, and unknown disturbances without the detailed knowledge of robot manipulator, while
resulting in an improved tracking performance. Lastly, in order to validate the effectiveness of the proposed
approach, the comparative simulation results of two-degrees of freedom robot manipulator are presented.
Design and development workshop interior design and furniture sectionIJERA Editor
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Crystal Growth and Studies of Dihydrogen Phosphates of Potassium and Ammonium...IJERA Editor
A nonlinear optical (NLO) material Potassium dihydrogen phosphates (KDP) and Ammonium dihydrogen
phosphates (ADP) are grown by slow evaporation solution growth technique. The FTIR studies confirm the
presence of the functional group in the grown crystal. The optical transmittance studies show that the crystal has
transparence in the entire visible and IR region. The thermal stability of the materials was assessed by TG/DTA
analysis. The mechanical stability of the grown crystals was analyzed by Vicker’s microhardness test. The
dielectric behavior of the crystals was tested by dielectric analysis. The second harmonic generation (SHG) of
KDP is confirmed by Kurtz and Perry powder technique using Nd: YAG laser.
Loss Calculation in Free Space Optical CommunicationsIJERA Editor
Free space optical (FSO) system is an alternative approach to replace the general optical
communication in many applications .In this system signal is propagating through the air as a transmission
medium. At present FSO system are capable of handling the data up to 2.5 Gbps. It supports audio, video and
data through air as a transmission media. This will use optical carrier in the infrared and visible regions to
establish the links. In this paper we calculated different losses in the system and specified various advanced
methods for the future FSO. It also finds in many applications such as Military, Metro network extension,
Telecommunication networking and Last-mile access.
Corrosion Inhibition of Carbon Steel In Sulfuric Acid by Sodium CaprylateIJERA Editor
The interaction of a sodium salt of octanoic acid, sodium caprylate (SC), with a carbon steel (CS) surface was
investigated, using range of experimental techniques. It was shown that SC acts as a good CS general corrosion
inhibitor, yielding a maximum corrosion inhibition efficiency of 77%. This high inhibition efficiency is
maintained even at higher temperatures. It was determined that SC inhibits both partial corrosion reactions, and
can thus be considered to be a mixed-type inhibitor. The adsorption of SC on the CS surface was described by
the Langmuir adsorption isotherm. It was found that this process is spontaneous, irreversible and driven by the
entropy gain. The CS surface morphology was studied by SEM and it was demonstrated that SC is a very
effective general corrosion inhibitor of CS. This also was confirmed by contact angle measurements which
showed that the CS surface became more hydrophobic when the SC was added to the solution.
Method to Measure Displacement and Velocityfrom Acceleration SignalsIJERA Editor
This paper discusses a methodology for measuring the displacement and velocity vibration of a
structure from a noisy acceleration signal. Digital FIR (finite impulse response)filters were used to remove the
noise present in the signal as well to eliminate numerical integration problems which produce offsets in velocity
and displacement amplitudes. The choice of this type of filter aims to prevent the signal delay that may cause
distortions in numerical integration process. To validate this methodology the defined procedure was applied to
determine the deflection history of a beam with random excitation base. The acceleration signals considered as
input data were obtained from two piezoelectric accelerometers used to measure the vibration of the base and
the beam response. The correlation was defined between the stress measured by a strain gage and the stress
calculated from its deflection. The result was great, enabling the application of this methodology to determine
the history of displacement and velocity of the structure's vibration, through signals measured with
accelerometers.
The Nanotechnological Innovation in Food IndustryIJERA Editor
The perspectives of direct energy action (DEA) technologies are discussed. The new classification of DEA
technologies is proposed. The possibilities of DEA technologies using in food nanotechnologies are analyzing.
The concepts of heat mass transfer during extraction and drying are considered in terms of food industry. The
hydrodynamic flows from food raw capillary structures are classified. The conditions of laminar and turbulent
barodiffusion are determined. The problem of combined DEA technologies processes simulation and the
objectives of experimental research are formulated. The new dimensionless number called as the number of
energy action is discussed. It is shown that the impulse electromagnetic field is an effective instrument for DEA
technology implementation
Supplier Selection and Order Allocation Models in Supply Chain Management: A ...IJERA Editor
Supplier selection decisions are an important component of production and logistics management for many
firms. Such decisions entail the selection of individual suppliers to employ and the determination of order
quantities to be placed with the selected suppliers. This paper reviews supplier selection and order allocation
models based on an extensive search in the literature (170 paper during 2000-2016) and tries to show their
contribution to supply chain management. After discussing different methods and their applications, the most
prevalently used approaches and criteria are presented. In the second step, different attributes of these papers are
defined and finally issues for future research are recommended
Comparative Study of Girders for Bridge by Using SoftwareIJERA Editor
According to various research papers, it has been found that composite bridge gives the maximum strength in
comparison to other bridges and the design and analysis of various girders for steel and concrete by using
various software for composite bridge design for girder. In this project, efforts will make to carry outto check
the analysis of girder by using SAP2000 software. Hence, in this project determine three girders which can be
effective to the composite bridges.
An Integrated Parametric Approach To Landfill Site Selection Fuzzy GIS-Based ...IJERA Editor
Landfill site selection in an urban area is a critical issue in the urban planning process because of enormous
impact on the economy, ecology, and the environmental health of the region with the growth of the
urbanization, larger amount of wastes are produced and unfortunately the problem gets bigger every day. A
selection of proper waste disposal site is a function of many parameters can be involved under the Environment,
Planning & Social Functions. GIS based mapping and subsequent image analysis is proposed to be done for
each of the correlating criteria for each parameter. The fuzzy multi criteria decision making (FMCDM) is used
to rank different land fill sites based on decisions given by a group of experts. The selected site can be further
confirmed through GIS application. This paper highlights the explained approach.
Feasibility Study of Synthesis of Nanostructured Aluminum Nitride Through Sol...IJERA Editor
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc
Identification and Classification of Leaf Diseases in Turmeric PlantsIJERA Editor
Plant disease identification is the most important sector in agriculture. Turmeric is one of the important
rhizomatous crops grown in India. The turmeric leaf is highly exposed to diseases like rhizome rot, leaf spot,
and leaf blotch. The identification of plant diseases requires close monitoring and hence this paper adopts
technologies to manage turmeric plant diseases caused by fungi to enable production of high quality crop yields.
Various image processing and machine learning techniques are used to identify and classify the diseases in
turmeric leaf. The dataset with 800 leaf images of different categories were pre-processed and segmented to
promote efficient feature extraction. Machine learning algorithms like support vector machine, decision tree and
naïve bayes were applied to train the model. The performance of the model was evaluated using 10 fold cross
validation and the results are reported.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
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SIMULATION OF MEMS MICROHOTPLATE FOR METAL OXIDE GAS SENSORS: REVIEWIJEEE
Simulation of gas sensor with integrated micro hotplate (MHP) of ultra low power consumption is reviewed. Various parameters of gas sensor and MHP as power, temperature ,heat insulation ,stress analysis and deflection is studied using various Multiphysics simulation tools like ANSYS and Conventorware
VIBRATION ANALYSIS FOR DAMAGE DETECTION IN COMPOSITE PLATE BY USING PIEZOELEC...IAEME Publication
This study focuses on an active monitoring method for damage detection applied to composite structures. Different specimens made up of fiber epoxy resin in the form of composite structures are studied. Wavelet analysis methods are adopted to post process the raw monitored signal. A new damage signature is introduced to determine the presence and extent of damage in composites, while eliminating the influence of different distances between the active actuator and active monitoring elements. The proposed method is shown to be effective, reliable, and straightforward for the specimens considered in the present study, which are composed of different materials and suffer various levels of damage. An online real-time active monitoring system for
damage detection is described that is based on this research.
A DEEP LEARNING APPROACH FOR DENOISING AIR-COUPLEDULTRASONIC RESPONDS DATAijaia
Ensuring material quality is a central objective in production and manufacturing. Non-contact nondestructive testing methods without the use of coupling media are of particular interest with regard to mechanical or biochemical properties of the material. For this purpose, air-coupled ultrasonic is a useful method for quality control. The challenge is the poor signal-to-noise ratio, which makes it difficult to apply the classical approaches. This makes it impossible to distinguish between defect structures and noise. We are developing a method for denoising air-coupled ultrasonic data by applying deep neural networks by
using a geometry-analytical component that detects defect structures. During the evaluation we show that we are able to obtain the data almost free of noise, so that incorrectly classified noisy pixels are mainly located at the edges of the defect structures, which cannot be clearly delimited. It is shown that the quality of the data is significantly improved for detection processes.
A DEEP LEARNING APPROACH FOR DENOISING AIR-COUPLEDULTRASONIC RESPONDS DATAgerogepatton
Ensuring material quality is a central objective in production and manufacturing. Non-contact nondestructive testing methods without the use of coupling media are of particular interest with regard to
mechanical or biochemical properties of the material. For this purpose, air-coupled ultrasonic is a useful
method for quality control. The challenge is the poor signal-to-noise ratio, which makes it difficult to apply
the classical approaches. This makes it impossible to distinguish between defect structures and noise. We
are developing a method for denoising air-coupled ultrasonic data by applying deep neural networks by
using a geometry-analytical component that detects defect structures. During the evaluation we show that
we are able to obtain the data almost free of noise, so that incorrectly classified noisy pixels are mainly
located at the edges of the defect structures, which cannot be clearly delimited. It is shown that the quality
of the data is significantly improved for detection processes.
This paper represent the innovative trends
and aspect of green nanotechnology development
challenges and opportunities in the field of alternative
technology to assist in future developments in this field.
There are various innovative applications of green Nanotechnology
in different- different fields like Energy,
Medicine and Drugs, Nano bio-technology, Nano devices,
Optical Engineering, Defence & Security, Bio
Engineering,Cosmetics,Nano Fabrics etc. Nanotechnology
improves the process of production and also improves the
quality of products. It works at the molecular level and
utilizes the more advanced concept, idea and research for
the development of different fields and production.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
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1. Shwetha Meti et.al. Int. Journal of Engineering Research and Applications www.ijera.com
ISSN: 2248-9622, Vol. 6, Issue 4, (Part - 1) April 2016, pp.23-31
www.ijera.com 23|P a g e
MEMS Piezoresistive Pressure Sensor: A Survey
Shwetha Meti*, Kirankumar B. Balavald*, B. G. Sheeparmatti*
*(Department of Electronics and Communication, Basaveshwar Engineering College, Bagalkot-587102
ABSTRACT
Piezoresistive pressure sensors are one of the very first products of MEMS technology, and are used in various
fields like automotive industries, aerospace, biomedical applications, and household appliances. Amongst
various transduction principles of pressure sensor piezoresistive transduction mechanism is widely used. Over a
decade therehas been tremendous improvement in the development of the design of piezoresistive pressure
sensor starting with the invention of piezoresistance in the silicon to the recent piezoresistive pressure sensor
materials. Because of its high sensitivity, high gauge factor, independent to the temperature, linear operation
over a wide range of pressure, and many more advantages. This paper provides survey of piezoresistive pressure
sensor including their pressure sensing mechanism, evolution, materials, design considerations, performance
parameter that to be considered and the fabrication process used
Keywords-MEMS, Pressure sensor, Piezoresistor, Silicon
I. INTRODUCTION
In conjunction with temperature, pressure
is one of the major physical quantities in our
environment. A pressure sensor often acts as a
transducer; it produces a signal as a function of the
pressure imposed. MEMS pressure sensors are
covering foremost part of the sensor market in
contemporary years and are fast developing with
brand new capabilities. Pressure sensors are used in
many applications like aerodynamics, biophysics,
automobile, safeguards and many more domestic
applications. Various types of pressure sensors can
be categorized based on the sensing mechanisms
they are. 1.1 Absolute pressure sensor measures
static, dynamic or whole pressure with reference to
a vacuum. 1.2 Gauge pressure sensor calculates the
pressure relative to atmospheric pressure. When it
shows zero, then the pressure it is measuring is
same as the ambient pressure. 1.3 Relative pressure
sensor measures static, dynamic or total pressure
with regards to the ambient pressure. 1.4 Optical
pressure sensor techniques include the use of
anphysical change in the optical fiber to detect the
strain due to an applied pressure. This technology
is employed in many challenging applications
where the measurement may be highly remote,
under high temperature, or may benefit from
applied sciences inherently immune to
electromagnetic interference. 1.5 Differential
pressure sensor measures the difference between
two pressures, one connected with each side of the
sensor. Differential pressure sensors are used to
measure many properties like pressure drops
through oil filters or air filters, fluid levels or flow
rates. 1.6 Piezoresistive pressure sensor uses
the piezoresistive effect of bonded strain gauges to
detect the strain due to an applied pressure,
resistance increasing as pressure deforms the
material. Common methods that uses piezoresistive
technologies are Silicon (Mono crystalline),
Polysilicon Thin Film, Bonded Metal Foil. 1.7
Capacitive pressure sensor uses a diaphragm and
pressure cavity to create a variable capacitor to
detect strain due to applied pressure, capacitance
decreasing as pressure deforms the diaphragm.
1.8Resonant pressure sensor uses the changes
in resonant frequency in a sensing mechanism to
measure stress, or changes in gas density, caused
by applied pressure.
Many MEMS instruments were
manufactured and commercialized from several
years and have reached consumer. The present
pressure sensors going through many challenges
that has to be used in the application like high
pressure. Temperature is a main factor in the
efficiency of MEMS pressure sensor, were these
have to be used in many applications like aerospace
utility and harsh environment. Consequently, for
this kind of environment special sensing devices
are requiring to adapt a high temperature and high
pressure environment. Among all the various type
of MEMS pressure sensor piezoresistive pressure
sensors are widely used, because these sensors
provides a high sensitivity and it allows a linear
operation over a wide range of pressure.
Piezoresistive pressure sensors are one of the very
first products of MEMs technology. Those products
are broadly used in biomedical applications,
automotive enterprises and household appliances.
The piezoresistive pressure sensor have mainly
been studied and commercialized because of their
high yield and wide dynamic range. A silicon based
pressure sensor is one of the major applications of
the piezoresistive sensor. Recently MEMS situated
technologies includes silicon (Si), silicon on
insulator (SOI), silicon on sapphire (SOS), silicon
carbide (SiC), steel, carbon nanotubes (CNT) and
RESEARCH ARTICLE OPEN ACCESS
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diamond had been observed to be in a position to
furnish the critical ruggedness to be capable to
adapt and provide the better performance in harsh
environment. This paper focus on the survey of
MEMS based piezoresistive pressure sensor,
current trends involved in development of
piezoresistive pressure sensor and their outlook.
Section II explains about the evolutions of
piezoresistive pressure sensor. Principle and
sensing mechanism of piezoresistive pressure
sensor is explained in section III. Section IV is
about the materials that are used in the design of
diaphragm and their properties. Section V and VI
discuss about the performance parameter and the
design consideration of the piezoresistive pressure
sensor. The fabrication of the piezoresistive
pressure sensor is discussed in section VII.
II. EVALUTION OF PIEZORESISTIVE
PRESSURE SENSOR
Ever since the discovery of
Piezoresistance in silicon by C.S.Smith in1954 [1]
silicon based micro pressure sensors have been
extensively studied over the past three decades.
Pfann and Thurston [2] were among the first to
realize a working of MEMS based pressure sensor
designed using two longitudinal and two transverse
diffused piezoresistors in the Whetstone's bridge
for better sensitivity. Kanda [3] in his work has
presented a model which enables the calculation of
piezoresistive coefficients as a function of doping
concentration and temperature. Enhancing the
sensitivity has also been a main issue in the
research of micro pressure sensors. Design
modifications like employing a bossed diaphragm
and multiple diaphragms [4, 5] and material
modification by using phosphorous diffused
polysilicon piezoresistors [6] polymer diaphragms
and alternate piezoresistive materials [7-10] have
also been studied. The other technology can be
brought to solve the isolation problem of devices
and substrates, but increases the fabrication cost
greatly. The discovery of piezoresistive effect in
polysilicon in the 1970s [11] facilitates its
applications for sensing devices [12, 13]. As for
polysilicon, the p-n junction isolation is avoided, so
that the devices can work at higher temperatures.
Moreover, polysilicon based devices have the
advantages of low cost, facile processing and good
thermal stability, compared to homogeneous silicon
based devices. It can be seen that it is necessary to
investigate the piezoresistive properties of
polysilicon and built up the theoretical model. The
experimental results reported by other researchers
indicated that the GF of Polysilicon common films
(PSCFs, film thickness ≥ 200 nm) reaches the
maximum as the doping concentration is at the
level of 1019 cm3
, and then decreases drastically as
doping concentrations are increased further [14, 15-
17]. Based on this phenomenon, the existing
piezoresistive theories of Polysilicon were
established during 1980s~1990s and used to predict
the process steps for the optimization of device
performance.
Later years carbon nanotubes have drawn
much attention since their discovery in 1991
because of their unique electronic and mechanical
properties. In 1991, multi-walled nanotubes were
first discovered by Ijima by arc-discharge
technique when he saw fine threads in a bit of shoot
under electron microscope. The strands were very
thin and long tubes of pure carbon. SWNTs were
synthesized for the first time by Ijima and Ichihashi
[18] and Bethune et al. [19] in 1993 using metal
catalyst in arc-discharge method. Laser-ablation
technique was used by Thess et al. [20] in 1996 to
produce bundles of aligned SWNTs. For the first
time, catalytic growth of MWNTs by CVD was
proposed by Yacaman et al. [21]. Liu [22] and Dai
[23] demonstrated that piezoresistive pressure
sensors can be realized with CNTs. They grew
SWNTs on suspended square polysilicon
membranes. When uniform air pressure was
applied on the membranes, a change in resistance
in the SWNTs was observed. Moreover, the
membrane was restored to its original condition
when the gas was pumped out, indicating that the
process is reversible. Dharap et al.[24] argued that
the conventional sensors have disadvantage that
they are discrete point, fixed directional, and are
not embedded at the material level. To overcome
these limitations, they developed a CNT film
sensor for strain sensing on macro scale. The
sensor was based on the principle that the
electronic properties of CNTs change when
subjected to strains. In recent years high
temperature pressure sensor is one of the hot
research topics in the industry. Because of the
special environments they are used in, the
requirements for the design and manufacture of the
sensor are very strict. It is important to research
high temperature pressure sensors for every walk of
life [25, 26]. So Silicon carbide (SiC) has been
recognized as an appropriatesemiconductor
material for harsh environments such asspace
applications and terrestrial applications in the
aeronautical,automotive and petrochemical fields
proposed Staufferet al; George et al. 2006 Many
studies show thatSiC devices are capable of
operating well in these applicationsthat involve
high-temperature, high-radiation andcorrosive
environment by Azevedo and Jones;
WrightandHorsfall [27, 28] 2007.
Another material that can withstand the
high temperature and high pressure is a SOI. We
know that the temperature dependence of the
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piezoresistive effect in silicon is well documented
in the literature. It is known how the piezoresistive
coefficients change with the temperature. The
temperature limit has been verified up to 175 °C for
silicon sensors and up to 500 °C for silicon-on-
insulator (SOI) technology [29] by Fraga et al.
2011. Later Haisheng San, Zijun Song, Xiang
Wang, Yanlizhao, and Tuxi Y. U, proposed that
the silicon piezoresistive pressure sensor is a
mature technology in industry, but when the
pressure sensors are operated in extremely harsh
environment, such as vibration, shock and
environment conditions with humidity,
alkalescency or acidity, electrostatic particles and
so on, its requirement in terms of reliability and
stability is more rigorous than that of many
advanced applications so for these application we
have to choose a SOI rather than silicon [30].
III. PIEZORESISTIVE PRESSURE
SENSING MECHANISM
Piezoresistive, capacitive, optical,
resonance, acoustic transduction principle used in
the contemporary work within the progress of the
micro machined pressure sensor modelling, design
and fabrication used to be reviewed in [31]. Among
these pressure sensor transduction principle,
piezoresistive and capacitive transduction
mechanisms have been widely adopted in various
fields. Many commercialized MEMS pressure
sensor [32-36] uses a piezoresistive transduction
mechanism in order to shows the pressure change
in the resistance. Most researchers preferred
piezoresistive technique, because the properties of
silicon material have been well established and the
facilities of current silicon foundry can be utilized
for batch fabrication. And also piezoresistive
pressure sensor has excessive high gauge factor but
it has 0.27% per °C of temperature coefficient of
Piezoresistivity (TCP). The design of piezoresistive
pressure sensor consists of piezoresistive element
placed on a top of the diaphragm. Placement of
piezoresistive element on the square diaphragm is
very important design consideration to achieve the
required sensitivity. The optimal location to place
the piezoresistive material would be in the region
of high stress on the diaphragm. Then these
resistors are connected in the form of Whetstone's
bridge [1, 37]. The application of pressure beneath
the sensor causes a deflection of the membrane and
this causes a change in resistance of the
piezoresistive elements. As a result, the calculation
of stress distribution and deflection in accordance
with the applied pressure becomes pivotal.
These forms of piezoresistive based
transducers depend on the piezoresistive effect
which occurs when the change in electrical
resistance of a material in response to the
mechanical strain is applied [38]. In metals, this
effect is realized when the change in geometry with
applied mechanical strain results in a small increase
or decrease in the resistance of the metal. The
piezoresistive effect in silicon is primarily due to its
atomic level. As stress is applied, the average
effective mass of the silicon carrier will either
increases or decreases (depending on the
orientation of the crystallographic, direction of the
stress, and the direction of the current flow). This
type of change alters the silicon carrier mobility
and hence it results in the change in its resistivity.
When piezoresistive element are placed in the
Wheatstone bridge configuration and it is attached
to the pressure-sensitive diaphragm, a resistance
change in the material is converted in to an output
voltage which is proportional to the applied
pressure as shown in the Fig.1.
Fig.1. Conventional pressure sensor model
Fig.2. Wheatstone bridge circuit.
Fig.2. shows the Wheatstone bridge
circuit, a Wheatstone bridge consists of a four
piezoresistive material labeled as R1, R2, R3 and R4
respectively. The resistance [R] of a piezoresistive
material is given by
R= ρ
𝑳
𝑨
(1)
Where ρ is the resistivity of a piezoresistor, L is the
length of a piezoresistor; A is the area of a
piezoresistor. Wheatstone bridge is mounted on the
diaphragm. When the pressure is applied to the
diaphragm, the diaphragm experiences the sheer
stress due to which the diaphragm deforms in the
direction of pressure imposed. Due to the
deformation of the diaphragm, the piezoresistors
mounted on the diaphragm in a Wheatstone bridge
format stretches. As the piezoresistors stretches, the
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length increases while the area decreases. From
equation (1), if length increases and area decreases,
there will be incremental change in the resistance
of a piezoresistors and effectively decreases the
output voltage.
IV. MATERIALS OF PIEZORESISTIVE
PRESSURE SENSOR
In the above discussion it is clear that
depending on the application we have to use a
different piezoresistive material for the model, like
silicon (Si), silicon on insulator (SOI), silicon on
sapphire (SOS), silicon carbide (SiC), steel, carbon
nano tubes (CNT) and diamond. However the
principle remains same as the piezoresistive
mechanism of pressure sensing. The material used
to design the diaphragm on which the
piezoresistive materials are placed, plays on very
important role in deciding the application of a
pressure sensor. Table 1 and 2lists the properties of
various diaphragm and piezoresistive material
respectively.
Table 1 Properties of various diaphragm materials
Table 2 Properties of various
piezoresistivematerials
In the piezoresistive pressure sensor
output signal is from the Wheatstone bridge. The
resistance of the bridge is distributed in four
directions. The output signal Vout is Vin∆R/R. Vout
is the output voltage (V), Vin is the input signal
voltage (V), ∆R is the change in resistance (KΩ),
and R is the initialvalue of the resistance (KΩ). The
amount of change in voltage sensitivity of resistors
is [39].
∆R/R = 𝛑𝒍 𝛔𝒍 + 𝝅 𝒕 𝝈 𝒕 (2)
Where 𝜎𝑙is the longitudinal stress parallel to the
current direction in the internal of resistance
(N/𝑚2
), 𝜎𝑡is the transverse stress perpendicular to
the current direction (N/𝑚2
), π𝑙 is the longitudinal
piezoresistive coefficient of silicon (𝑚2
/𝑁), the
same direction as the longitudinal stress, π𝑡is the
transverse piezoresistive coefficient of silicon
(𝑚2
/𝑁), the same direction as the transverse stress.
Table 3 shows the piezoresistive coefficient for
<100> silicon wafer.
Table 3 Piezoresistive coefficients of silicon
V. PERFORMANCE PARAMETERS
When the pressure is applied on the diaphragm, it
tends to get deformed, having a maximum
displacement at the centre of the diaphragm. The
value of displacement decreases near the fixed ends
of the diaphragm. The quantity of displacement is
measured at the centre of the diaphragm [40] using
the following equation
X =
𝟎.𝟎𝟎𝟏𝟐𝟔𝑷𝑳 𝟒
𝑫
(3)
Where P is the Pressure applied on the diaphragm,
L is the Length of the diaphragm, and D is the
Bending rigidity of the diaphragm material and is
given as
D =
𝑬𝒕 𝟑
𝟏𝟐(𝟏−𝒗 𝟐)
(4)
Where E is the Young’s Modulus of diaphragm
material, t is the thickness of the diaphragm, and v
is the Poisson’s ratio of the diaphragm material.
The amount of sheer stress experienced at the mid-
point of the diaphragm [41] is given as
ρ = (
𝑳
𝒕
) 2
(5)
It can be seen from (3) and (5) is that, increase in
the pressure applied on the diaphragm, increases
the sheer stress at the mid-point of the diaphragm,
also increases the displacement or deformation of
the diaphragm. The displacement of the diaphragm
also depends on the dimensions of the diaphragm
as well as the stiffness property (Young’s modulus)
of the diaphragm material. When the pressure is
applied on the diaphragm with four blocks as
piezoresistor, the stress induced in the diaphragm
change the resistance of piezoresistor due to
piezoresistive effect. The change in the resistance
of the piezoresistor is denoted by ΔR. Due to the
deformation of the diaphragm in the direction of
pressure applied, it is said that the length of the
piezoresistor increases which in turn increases the
resistance of the piezoresistive material (using
Sl.
No
Materials Density Young’s
Modulus
Poisson’
s ratio
1. Silicon di oxide 2270 70 0.17
2. Poly Silicon 2320 169 0.22
3. Steel AISI 4340 7850 205 0.28
4. Al203 3970 393 0.27
5. Si3N4 3310 317 0.23
6. Germanium 5323 103 0.26
7. Al 2700 70 0.25
8. Cu 8960 120 0.34
Sl.
No
Materials Density Young’s
Modulus
Poisson’s
ratio
1. Single
crystalline Si (n,
p type)
2270 70 0.17
2. Carbon
Nanotubes
1600 1000 0.2
3. Diamond 3.5 10.35 ---
4. SIC 3.21 476 0.19
5. Silicon 2330 160 0.22
6. SOS 3.97 250-400 0.29
7. Polycrystalline
Si
2330 160 0.23
Sl.
No
Wafer
type
π𝑙 π𝑡 Orientation
1. P-type -31.6 -17.16 <110>
2. N-type 71.8 -66.3 <110>
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equation 1). Thus it can be concluded that, as the
pressure increases, the resistance of the
piezoresistor will also increases linearly.The next
parameter is the output voltage across the
Wheatstone bridge. The output voltage of the
Wheatstone bridge depends on the input voltage
applied to the bridge circuit and also the resistance
values of all the four piezoresistive materials.
Hence, as the resistance of the piezoresistive
materials changes due to the applied pressure, the
output voltage of the Wheatstone bridge also
varies. The output voltage [Vout] across the
Wheatstone bridge circuit is given by,
Vout = [
𝑹𝟐𝑹𝟑−𝑹𝟏𝑹𝟒
(𝑹𝟏+𝑹𝟐)(𝑹𝟑+𝑹𝟒)
] Vin (6)
Where Vin is the Input voltage applied to
Wheatstone bridgefrom (6), when R2R3 = R1R4,
Vout= 0. This means that the bridge is in the
balanced condition and theoretically no pressure
is applied onto the diaphragm. When there is no
pressure on the diaphragm, the resistance values
of all the piezoresistive elements will be
theoretically identical, hence Vout = 0. But
practically it may be difficult to fabricate the
piezoresistive elements of equal resistances, due
to which the output voltage may not be zero when
no pressure is applied. The relation of electric
field in the vicinity of surface of the diaphragm
with applied stress is given by (7).
E = ρJ + ρρJ (7)
Where ρ is the resistivity of piezoresistors, J is
the current in piezoresistors, and Δρ is the
induced change in resistivity. This is given by the
equation
ρρ= ρ. ρ
Where π is the piezoresistance tensor and γ is the
shear stress given by (5).The performance of any
model can be estimated based on the sensitivity
of the sensor to the pressure applied and the
gauge factor. For the system to be better, it should
be highly sensitive. In other words, there should
be large decrease in the output voltage and large
increment in the resistance of piezoresistive
element due to a small increase in the pressure
applied to call a device as highly sensitive. Gauge
factor is another parameter which determines the
performance of the piezoresistive pressure sensor
[42]. The Gauge factor of the pressure sensor is
the change in resistance to the amount of
volumetric strain acting on it. It is given by
G =
∆𝑹
𝑹𝜺
(8)
Where ε is the Strain of the pressure sensor
The Gauge factor value should be large
(in the range of 500 to 1000) to indicate the better
performance of the pressure sensor.The
sensitivity of the pressure sensor is defined as the
relative change in the output voltage per unit of
applied pressure [43]. The sensitivity of the
piezoresistive pressure sensor is given by.
S=
𝟏
𝑽𝒊𝒏
∆𝑽
∆𝑷
(9)
Where S is the sensitivity of the pressure sensor,
ΔV is the change in the output voltage, and ΔP is
the change in the pressure applied. The output
voltage of the pressure sensor without any pressure
being applied is called an offset voltage. This is due
to mainly two reasons. The first one is due to some
residual stress on the membrane. And the second
one, which is main reason, is variability in the four
resistors. While the resistors are processed at the
same time, there are some variations. The offset
voltage can be compensated by connecting external
resistors. It can be compensated using
compensating resistors along with electronics.
VI. DESIGN CONSIDERATION
6.1. Fracture Stress:
Fracture stress is a property which
describes the ability of a material containing a
crack to resist fracture, and is one of the most
important properties of any material for many
design applications. The linear-elastic fracture
stress of a material is determined from the stress
intensity factor at which a thin crack in the material
begins to grow. It is denote (σfracture)
6.2. Yield Strength:
A yield strength or yield point is the
material property defined as the stress at which a
material begins to deform plastically. Prior to the
yield point the material will deform elastically and
will return to its original shape when the applied
stress is removed. Once the yield point is passed,
some fraction of the deformation will be permanent
and non-reversible.
6.3. Burst Pressure:
Another important design consideration of
a piezoresistive pressure sensor is a burst pressure.
We know that as the applied pressure on the
diaphragm increases, the stress on the diaphragm
increases correspondingly. As a result, when the
maximum stress on any portion of the diaphragm
exceeds the yield strength of the diaphragm
material, the diaphragm will burst. While this burst
pressure governs the maximum operating pressure
of a pressure sensor, the linearity of operation
determines the maximum pressure up to which the
sensor can be used within the limits of the specified
accuracy. The burst pressure is decided by a
number of factors including diaphragm shape,
thickness, lateral dimensions, ruptures stress of the
material and diaphragm surface roughness and is
given by [44].
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𝑷 𝒃=
𝟑.𝟒𝑭 𝑴𝒂𝒙 𝒉 𝟐
𝑨(𝟏−𝒗 𝟐)
(10)
Where 𝐹 𝑀𝑎𝑥 is theFacture stress, h is the
Diaphragm thickness, 𝑣is the Poisson's ratio, A is
the Diaphragm area.
6.4. Diaphragm dimension:
As the stress on the piezoresistors is due to
the stress on the diaphragm, it is important to
choose the thickness and size of the diaphragm
carefully in order to obtain the best output
characteristics from the sensor. Pressure sensors
with thinner diaphragms give better sensitivity
whereas thicker diaphragm gives better linearity.
Usually, the diaphragm in a pressure sensor is
modified as a square diaphragm with all the edges
clamped. A diaphragm can be considered as a thin
diaphragm, if the ratio of thickness to the length of
diaphragm is less than 1/20, [44]. The small
deflection theory for bending of thin plates assumes
that the deflection of midpoint of surface of the
diaphragm must be small compared to the thickness
of the plate and the maximum deflection must be
less than 1/5th
of the thickness of the diaphragm
[45].
6.5. Temperature Coefficient
ofResistance(TCR):
The change in the resistance of the
material per degree Celsius change of temperature
is known as the temperature coefficient of
resistance. A positive coefficient of the material
means that its resistance increases with increases in
the temperature (Pure metal typically have a
positive temperature coefficient of resistance). A
negative coefficient of the material means that its
resistance decreases with an increases in the
temperature (Semiconductor materials like carbon,
silicon, germanium typically have a negative
temperature coefficient of resistance). The equation
for the TCR is given by,
R= Rref[1+ρ(T-Tref)] (11)
Where α is the temperature coefficient of
resistance, R is the resistance of the material at
temperature T, Rref is the reference resistance, T is
the temperature in degree Celsius, and Tref is the
reference temperature.
VII. FABRICATION METHODOLOGY
Many fabrication methods have been
investigated to date. They all aim at a thin
monocrystalline silicon film on top of an insulator
with defect densities as low as in bulk material. The
best compatibility with standard silicon processing
techniques can be attained with sandwich
structures. A typical fabrication of the
piezoresistive pressure sensor is shown in Fig.3. It
is made up of <100> crystal orientation of the
silicon wafer and a membrane has been formed by
an anisotropic etching using a KOH etch stop, in
the <111> plane. Due to the nature of this etch; the
sides of the membrane are oriented along <110>
direction.
Fig.3. Fabrication of the piezoresistive pressure
sensor
A cross sectional view of fabrication of a pure
silicon based piezoresistive pressure sensors using
a standard silicon IC process is shown in the Fig.4.
The process of patterning the thin uniform layer of
silicon substrate on the wafer surface. The pure
silicon is hardened by baking and then selectively
removed by projection of light through a reticle
containing mask information. To form the
diaphragm selectively removes unwanted material
from the surface of the wafer using wet-etching
technique. In oxidation process wet oxidation
molecule convert silicon on the top the wafer to
silicon dioxide. After the deposition of silicon
dioxide layer piezoresistors are placed on the
diaphragm by diffusing the P-type silicon to form
bridge between the piezoresistors.
Fig.4. Cross sectional view of fabrication
ofpiezoresistive pressure sensor
VIII. CONCLUSION
Research activity in the areas related to the
piezoresistive pressure sensor is very broad and it
has made a phenomenal growth. In this paper, an
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attempt has been made to provide a review on
piezoresistive based pressure sensors, their various
mechanisms, materials used to design the
piezoresistive pressure sensor, different fabrication
process; performance parameters for the
piezoresistive pressure sensors are discussed. The
piezoresistive pressure sensor based on Wheatstone
bridge circuit is widely used by many reported
works. The exceptional properties, which allow
piezoresistive pressure sensors to be used in
sensors, has also been reviewed. MEMS pressure
sensor based on piezoresistive transduction
mechanism has lot of scope due to its high
sensitivity, stability and high temperature.
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ISSN: 2248-9622, Vol. 6, Issue 4, (Part - 1) April 2016, pp.23-31
www.ijera.com 31|P a g e
Ms SHWETHA METI obtained her B.E degree in
Basaveshwar Engineering College Bagalkot. Her
area of interest includes MEMS, Piezoresistive
pressure sensor, Capacitive pressure sensor, Digital
signals processing.
Prof. KIRANKUMAR. B.
BALAVALADcompleted his
M.Techfrom
VishweshwaryyaTechnological
University, Belagavi, Karnataka,
India in the year 2010. He is
pursuing his Ph.D in the area of
MEMS Piezoresistive Pressure Sensors. Presently
he is serving as, Assistant Professor, Department of
Electronics and Communication Engineering,
Basaveshwar Engineering College, Bagalkot,
Karnataka, India. He has published 20 papers in
national and international conference and journals.
His area of interest includes MEMS, Pressure
sensors, Electro thermal actuators, Wireless
networks, Statistical signal processing.
Dr. B. G. Sheeparmatti hascompleted his Ph.D in
the area of MEMS from Karnataka
University Dharwad, Karnataka,
India. He us currently serving as a
professor in Electronics and
Communication Engineering,
department Basaveshwar
Engineering College, Bagalkot, Karnataka, India.
He has successfully completed 2RPS schemes
approved by AICTE in the area of MEMS. He has
setup a low cost MEMS fabrication lab at the
department of Electronics and Communication
Engineering. He has more than 60 national,
international conference and journal papers to his
credit. His area of interest includes MEMS, MEMS
based actuators & sensors, Electromagnetic sensors
and actuators, Embedded system etc.
Electronics and Communication
Engineering from the Basaveshwar
Engineering College Bagalkot.
Pursuing Master degree in Digital
Communication from the
Basaveshwar