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Research paper thumbnail of Simulation of high sensitivity MEMS capacitive pressure sensor with small size and clamped square diaphragm

Majlesi Journal of Telecommunication Devices, 2016

In this paper a novel MEMS capacitive pressure sensor with small size and high sensitivity is pre... more In this paper a novel MEMS capacitive pressure sensor with small size and high sensitivity is presented. This sensor has the separated clamped square diaphragm and movable plate. The diaphragm material is polysilicon. The movable and fixed plates are gold and the substrate is pyrex glass. The mechanical coupling is Si 3 N 4 . In capacitive sensor the sensitivity is proportional to deflection and capacitance changes with pressure for this reason with this design is improved the sensitivity with small size. The size of this sensor is 350×350 (µm 2 ) and the thickness of diaphragm is 2µm with 1 air gap. This structure is designed by intellisuite software. In this simulation are shown the compare of polysilicon and polyimide diaphragms. Because in many previous works polysilicon and polyimide are used. In this MEMS capacitive pressure sensor the sensor sensitivity, diaphragm mechanical sensitivity for polysilicon(stress=100Mpa) diaphragm are 0.0074 (Pf/mmHg), 0.0042/mmHg), respectively ...

Research paper thumbnail of Design and Simulation High Sensitive MEMS Capacitive Pressure Sensor with Small Size for Glaucoma Treatment

World Academy of Science, Engineering and Technology, International Journal of Biomedical and Biological Engineering, 2016

Research paper thumbnail of Nonlinear modeling of a capacitive MEMS accelerometer using neural network

2008 33rd IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT), 2008

This paper presents a nonlinear model for a capacitive Microelectromechanical accelerometer (MEMA... more This paper presents a nonlinear model for a capacitive Microelectromechanical accelerometer (MEMA). System parameters of the accelerometer are developed using the effect of cubic term of the folded-flexure spring. To solving this equation we use FEA method. The neural network (NN) uses Levenberg-Marquardt (LM) method for training the system to have more accurate response. The designed NN can identify and predict the displacement of movable mass of accelerometer. The simulation results are very promising.

Research paper thumbnail of Pressure sensors based on MEMS, operating in harsh environments (touch-mode)

2008 33rd IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT), 2008

In this paper, Poly-crystalline silicon carbide (poly-sic) Micro-electromechanical systems (MEMS)... more In this paper, Poly-crystalline silicon carbide (poly-sic) Micro-electromechanical systems (MEMS) capacitive pressure sensor operating in harsh environment in touch mode is proposed, The principle of the paper is to design, obtain analytical solution and compare the results with the simulation for a circular diaphragm deflection before and after touch point. The sensor demonstrated a high temperature sensing capability up to 400°C, the device achieves a linear characteristic response and consists of a circular clamped-edges poly-sic diaphragm suspended over sealed cavity on a silicon carbide substrate. The sensor is operating in touch mode capacitive pressure sensor, The advantages of a touch mode are the robust structure that make the sensor to withstand harsh environment, near linear output, and large over-range protection, operating in wide range of pressure, higher sensitivity than the near linear operation in normal mode, The material is considered to be used for harsh environment is SiC (Silicon Carbide), Because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties and the application of pressure sensors in harsh environments are, such as automotive industries, aerospace, oil/logging equipments, nuclear station, and power station. We are simulating MEMS capacitive pressure sensor to optimize the design, improve the performance and reduce the time of fabricating process of the device. The proposed touch mode MEMS capacitive pressure sensor demonstrated diaphragm ranging from 150 μm to 360 μm in diameter, with the gap depth from 0.5 μm to 7.5 μm and the sensor exhibit a linear response with pressure from 0.05 Mpa to 10 Mpa.

Research paper thumbnail of Capacitive pressure sensors based on MEMS, operating in harsh environments

2008 IEEE International Conference on Semiconductor Electronics, 2008

Poly-crystalline silicon carbide (polysic) Micro-electromechanical systems (MEMS) capacitive pres... more Poly-crystalline silicon carbide (polysic) Micro-electromechanical systems (MEMS) capacitive pressure sensors operating at harsh environments (e.g. high temperature) are proposed because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties. The principle of this paper is, design, simulation. The application of SiC pressure sensors are in a harsh environments such as automotive industries, aerospace, oil/logging equipments, nuclear station, power station. The sensor demonstrated a high temperature sensing capability up to 400 °C, the device achieves a linear characteristic response and consists of a circular clamped-edges poly-sic diaphragm suspended over sealed cavity on a silicon carbide substrate. The sensor is operating in touch mode capacitive pressure sensor, The advantages of a touch mode are the robust structure that make the sensor to withstand harsh environment, near linear output, and large over-range protection, operating in wide range of pressure, higher sensitivity than the near linear operation in normal mode, so in this case some of stray capacitance effects can be neglected.

Research paper thumbnail of A Novel Neural Network Model of Capacitive MEMS Accelerometers

2008 IEEE International Conference on Semiconductor Electronics, 2008

This paper presents a nonlinear model for a capacitive Micro-electromechanical accelerometer (MEM... more This paper presents a nonlinear model for a capacitive Micro-electromechanical accelerometer (MEMA). System parameters of the accelerometer are developed using the effect of cubic term of the folded-flexure spring. To solving this equation we use FEA method. The neural network (NN) uses Levenberg-Marquardt (LM) method for training the system to have more accurate response. The designed NN can identify and predict the displacement of movable mass of accelerometer. The simulation results are very promising.

Research paper thumbnail of Analytical and Simulation Evaluation for Diaphragm's Deflection and its Applications to Touch Mode MEMS Capacitive Pressure Sensors

In this paper, An analytical and simulation solution for touch mode Micro-electromechanical syste... more In this paper, An analytical and simulation solution for touch mode Micro-electromechanical systems (M EMS) capacitive pressure sensor operating in harsh environment is proposed, The principle of the paper is to design, obtain analytical solution and compare the results with the simulation using coventor software for a circular diaphragm deflection before and after touch point. The material is considered to be used for harsh environment is SiC (Silicon Carbide), Because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties and the application of pressure sensors in harsh environments are, such as automotive industries, aerospace, oil/logging equipments, nuclear station, and power station. We are using coventor software for modeling and simulating of M EMS capacitive pressure sensor to optimize the design, improve the performance and reduce the time of fabricating process of the device. The device achieved a linear characteristic respon...

Research paper thumbnail of Evaluation for diaphragm's deflection for touch mode MEMS pressure sensors

In this paper, an analytical and simulation solution for touch mode Micro-electromechanical syste... more In this paper, an analytical and simulation solution for touch mode Micro-electromechanical systems pressure sensor operating in harsh environment is proposed. The principle of the paper is to design, obtain analytical solution and compare the results with the simulation using finite elements analysis for a circular diaphragm deflection before and after touch point. By looking at MEMS devices, when the diaphragm starts touching the fixed electrode by applying loads, it will have a major effect on the overall performance of the device. Therefore, one should consider the effect of touch mode in the system to achieve good linearity, large operating pressure range and large overload protection at output. As of so far the effect of touch mode has not been evaluated efficiently in the literatures. The proposed touch mode MEMS capacitive pressure sensor demonstrated diaphragm with radius of 180 µ m , the gap depth of 0.5 µ m and the sensor exhibit a linear response with pressure from 0.05 ...

Research paper thumbnail of Reactive Ion Etching of 4H-SiC Using SF6/O2 for MEMS Application

Deep Reactive Ion Etching (DRIE) of 4H-SiC performed using SF6/O2 plasma. The etching rates inves... more Deep Reactive Ion Etching (DRIE) of 4H-SiC performed using SF6/O2 plasma. The etching rates investigated as a function of the ratio of the O2 flow rate to total gas flow rate under different etching conditions such as the effect of power density, temperature, and the combination of chemistries on etching. The investigation was proven that the contribution and effect of the direct role of Oxygen to deep etching of SiC. An optimum value of O2 fraction of 60% to 40% Sulfur Hexafluoride (SF6) used to give high etching rate of 1.2μm/min. for maximum etching.

Research paper thumbnail of Theoretical formulation to evaluate capacitance for before and after touch point MEMS capacitive pressure sensors

Micro-electromechanical systems (MEMS) have received a great deal of attention in recent years. T... more Micro-electromechanical systems (MEMS) have received a great deal of attention in recent years. This is due to the great promise of increased miniaturization and Performance of MEMS devices over conventional devices. MEMS pressure sensors currently dominate the market for greater than atmospheric pressure sensors. In this paper, a theoretical and finite elements analysis (FEA) solution for Micro-electromechanical systems (MEMS) pressure sensor to evaluate capacitance for before and after touch point is proposed. By looking at MEMS devices, when the diaphragm starts touching the fixed electrode by applying loads, it will have a major effect on the overall of the capacitance. Therefore, one should consider the effect of touch mode capacitance value in the system to evaluate good linearity, large operating pressure range and large overload protection at output. As of so far the evaluation for capacitance value of touch point and after touch point has not been evaluated in the literatures. This paper presents the new analytical formula to approach for including the touchdown effect capacitance value of Microsystems. The proposed MEMS capacitive pressure sensor demonstrated diaphragm with radius of m  180 , the gap depth of m  5. 0 and the sensor exhibit linear response with pressure from 0.01 Mpa to 1.7 Mpa.

Research paper thumbnail of Simulation of high sensitivity MEMS capacitive pressure sensor with small size and clamped square diaphragm

Majlesi Journal of Telecommunication Devices, 2016

In this paper a novel MEMS capacitive pressure sensor with small size and high sensitivity is pre... more In this paper a novel MEMS capacitive pressure sensor with small size and high sensitivity is presented. This sensor has the separated clamped square diaphragm and movable plate. The diaphragm material is polysilicon. The movable and fixed plates are gold and the substrate is pyrex glass. The mechanical coupling is Si 3 N 4 . In capacitive sensor the sensitivity is proportional to deflection and capacitance changes with pressure for this reason with this design is improved the sensitivity with small size. The size of this sensor is 350×350 (µm 2 ) and the thickness of diaphragm is 2µm with 1 air gap. This structure is designed by intellisuite software. In this simulation are shown the compare of polysilicon and polyimide diaphragms. Because in many previous works polysilicon and polyimide are used. In this MEMS capacitive pressure sensor the sensor sensitivity, diaphragm mechanical sensitivity for polysilicon(stress=100Mpa) diaphragm are 0.0074 (Pf/mmHg), 0.0042/mmHg), respectively ...

Research paper thumbnail of Design and Simulation High Sensitive MEMS Capacitive Pressure Sensor with Small Size for Glaucoma Treatment

World Academy of Science, Engineering and Technology, International Journal of Biomedical and Biological Engineering, 2016

Research paper thumbnail of Nonlinear modeling of a capacitive MEMS accelerometer using neural network

2008 33rd IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT), 2008

This paper presents a nonlinear model for a capacitive Microelectromechanical accelerometer (MEMA... more This paper presents a nonlinear model for a capacitive Microelectromechanical accelerometer (MEMA). System parameters of the accelerometer are developed using the effect of cubic term of the folded-flexure spring. To solving this equation we use FEA method. The neural network (NN) uses Levenberg-Marquardt (LM) method for training the system to have more accurate response. The designed NN can identify and predict the displacement of movable mass of accelerometer. The simulation results are very promising.

Research paper thumbnail of Pressure sensors based on MEMS, operating in harsh environments (touch-mode)

2008 33rd IEEE/CPMT International Electronics Manufacturing Technology Conference (IEMT), 2008

In this paper, Poly-crystalline silicon carbide (poly-sic) Micro-electromechanical systems (MEMS)... more In this paper, Poly-crystalline silicon carbide (poly-sic) Micro-electromechanical systems (MEMS) capacitive pressure sensor operating in harsh environment in touch mode is proposed, The principle of the paper is to design, obtain analytical solution and compare the results with the simulation for a circular diaphragm deflection before and after touch point. The sensor demonstrated a high temperature sensing capability up to 400°C, the device achieves a linear characteristic response and consists of a circular clamped-edges poly-sic diaphragm suspended over sealed cavity on a silicon carbide substrate. The sensor is operating in touch mode capacitive pressure sensor, The advantages of a touch mode are the robust structure that make the sensor to withstand harsh environment, near linear output, and large over-range protection, operating in wide range of pressure, higher sensitivity than the near linear operation in normal mode, The material is considered to be used for harsh environment is SiC (Silicon Carbide), Because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties and the application of pressure sensors in harsh environments are, such as automotive industries, aerospace, oil/logging equipments, nuclear station, and power station. We are simulating MEMS capacitive pressure sensor to optimize the design, improve the performance and reduce the time of fabricating process of the device. The proposed touch mode MEMS capacitive pressure sensor demonstrated diaphragm ranging from 150 μm to 360 μm in diameter, with the gap depth from 0.5 μm to 7.5 μm and the sensor exhibit a linear response with pressure from 0.05 Mpa to 10 Mpa.

Research paper thumbnail of Capacitive pressure sensors based on MEMS, operating in harsh environments

2008 IEEE International Conference on Semiconductor Electronics, 2008

Poly-crystalline silicon carbide (polysic) Micro-electromechanical systems (MEMS) capacitive pres... more Poly-crystalline silicon carbide (polysic) Micro-electromechanical systems (MEMS) capacitive pressure sensors operating at harsh environments (e.g. high temperature) are proposed because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties. The principle of this paper is, design, simulation. The application of SiC pressure sensors are in a harsh environments such as automotive industries, aerospace, oil/logging equipments, nuclear station, power station. The sensor demonstrated a high temperature sensing capability up to 400 °C, the device achieves a linear characteristic response and consists of a circular clamped-edges poly-sic diaphragm suspended over sealed cavity on a silicon carbide substrate. The sensor is operating in touch mode capacitive pressure sensor, The advantages of a touch mode are the robust structure that make the sensor to withstand harsh environment, near linear output, and large over-range protection, operating in wide range of pressure, higher sensitivity than the near linear operation in normal mode, so in this case some of stray capacitance effects can be neglected.

Research paper thumbnail of A Novel Neural Network Model of Capacitive MEMS Accelerometers

2008 IEEE International Conference on Semiconductor Electronics, 2008

This paper presents a nonlinear model for a capacitive Micro-electromechanical accelerometer (MEM... more This paper presents a nonlinear model for a capacitive Micro-electromechanical accelerometer (MEMA). System parameters of the accelerometer are developed using the effect of cubic term of the folded-flexure spring. To solving this equation we use FEA method. The neural network (NN) uses Levenberg-Marquardt (LM) method for training the system to have more accurate response. The designed NN can identify and predict the displacement of movable mass of accelerometer. The simulation results are very promising.

Research paper thumbnail of Analytical and Simulation Evaluation for Diaphragm's Deflection and its Applications to Touch Mode MEMS Capacitive Pressure Sensors

In this paper, An analytical and simulation solution for touch mode Micro-electromechanical syste... more In this paper, An analytical and simulation solution for touch mode Micro-electromechanical systems (M EMS) capacitive pressure sensor operating in harsh environment is proposed, The principle of the paper is to design, obtain analytical solution and compare the results with the simulation using coventor software for a circular diaphragm deflection before and after touch point. The material is considered to be used for harsh environment is SiC (Silicon Carbide), Because of SiC owing excellent electrical stability, mechanical robustness, and chemical inertness properties and the application of pressure sensors in harsh environments are, such as automotive industries, aerospace, oil/logging equipments, nuclear station, and power station. We are using coventor software for modeling and simulating of M EMS capacitive pressure sensor to optimize the design, improve the performance and reduce the time of fabricating process of the device. The device achieved a linear characteristic respon...

Research paper thumbnail of Evaluation for diaphragm's deflection for touch mode MEMS pressure sensors

In this paper, an analytical and simulation solution for touch mode Micro-electromechanical syste... more In this paper, an analytical and simulation solution for touch mode Micro-electromechanical systems pressure sensor operating in harsh environment is proposed. The principle of the paper is to design, obtain analytical solution and compare the results with the simulation using finite elements analysis for a circular diaphragm deflection before and after touch point. By looking at MEMS devices, when the diaphragm starts touching the fixed electrode by applying loads, it will have a major effect on the overall performance of the device. Therefore, one should consider the effect of touch mode in the system to achieve good linearity, large operating pressure range and large overload protection at output. As of so far the effect of touch mode has not been evaluated efficiently in the literatures. The proposed touch mode MEMS capacitive pressure sensor demonstrated diaphragm with radius of 180 µ m , the gap depth of 0.5 µ m and the sensor exhibit a linear response with pressure from 0.05 ...

Research paper thumbnail of Reactive Ion Etching of 4H-SiC Using SF6/O2 for MEMS Application

Deep Reactive Ion Etching (DRIE) of 4H-SiC performed using SF6/O2 plasma. The etching rates inves... more Deep Reactive Ion Etching (DRIE) of 4H-SiC performed using SF6/O2 plasma. The etching rates investigated as a function of the ratio of the O2 flow rate to total gas flow rate under different etching conditions such as the effect of power density, temperature, and the combination of chemistries on etching. The investigation was proven that the contribution and effect of the direct role of Oxygen to deep etching of SiC. An optimum value of O2 fraction of 60% to 40% Sulfur Hexafluoride (SF6) used to give high etching rate of 1.2μm/min. for maximum etching.

Research paper thumbnail of Theoretical formulation to evaluate capacitance for before and after touch point MEMS capacitive pressure sensors

Micro-electromechanical systems (MEMS) have received a great deal of attention in recent years. T... more Micro-electromechanical systems (MEMS) have received a great deal of attention in recent years. This is due to the great promise of increased miniaturization and Performance of MEMS devices over conventional devices. MEMS pressure sensors currently dominate the market for greater than atmospheric pressure sensors. In this paper, a theoretical and finite elements analysis (FEA) solution for Micro-electromechanical systems (MEMS) pressure sensor to evaluate capacitance for before and after touch point is proposed. By looking at MEMS devices, when the diaphragm starts touching the fixed electrode by applying loads, it will have a major effect on the overall of the capacitance. Therefore, one should consider the effect of touch mode capacitance value in the system to evaluate good linearity, large operating pressure range and large overload protection at output. As of so far the evaluation for capacitance value of touch point and after touch point has not been evaluated in the literatures. This paper presents the new analytical formula to approach for including the touchdown effect capacitance value of Microsystems. The proposed MEMS capacitive pressure sensor demonstrated diaphragm with radius of m  180 , the gap depth of m  5. 0 and the sensor exhibit linear response with pressure from 0.01 Mpa to 1.7 Mpa.