scholarly journals A Micromachined Piezoresistive Pressure Sensor with a Shield Layer

2016 ◽  
Author(s):  
Gang Cao ◽  
Xiaoping Wang ◽  
Yong Xu ◽  
Sheng Liu
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Temperature Drift ◽  
Electrical Field ◽  
Piezoresistive Pressure Sensor ◽  
Improved Stability ◽  
Developed Pressure ◽  
Piezoresistive Pressure Sensors ◽  
P Type ◽  
The Impact

This paper presents a piezoresistive pressure sensor with a shield layer for improved stability. Compared with the conventional piezoresistive pressure sensors, p-type piezoresistors are covered by an n-type shield layer, which is formed by ion implantation. The proposed pressure sensors have been successfully fabricated by bulk micromachining techniques. The impact of electrical field on piezoresistors is studied by simulation. The temperature drift of the pressure sensor has been investigated by both simulation and experimental measurement. Characteristics of developed pressure sensors are tested from -40 C to 125 C. A sensitivity of 0.022 mV/V/KPa and a maximum non-linearity of 0.085% FS are measured for the fabricated sensor in a pressure range of 1 MPa. The temperature coefficients of resistance of shielded piezoresistors are found to be smaller than those of un-shielded ones. It is demonstrated that the shield layer is able to reduce the drift caused by electrical field and ambient temperature variation.

Modeling and Simulation of the Thermal Drift Characteristics of the Piezoresistive Pressure Sensor

2010 ◽  
Vol 2010 (HITEC) ◽  
pp. 000373-000378
Author(s):  
R. Otmani ◽  
N. Benmoussa ◽  
K. Ghaffour
Keyword(s):  
Thermal Behavior ◽  
Modeling And Simulation ◽  
Pressure Sensor ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Thermal Drift ◽  
Piezoresistive Pressure Sensor ◽  
Output Characteristics ◽  
Piezoresistive Pressure Sensors

Piezoresistive pressure sensors based on Silicon have a large thermal drift because of their high sensitivity to temperature (ten times more sensitive to temperature than metals). So the study of the thermal behavior of these sensors is essential to define the parameters that cause the drift of the output characteristics. In this study, we adopted the behavior of 2nd degree gauges depending on the temperature. Then we model the thermal behavior of the sensor and its characteristics.

Design and Optimization of a Highly Sensitive and Linearity Piezoresistive Pressure Sensor Based on a Combination of Cross Beam-Peninsula-Membrane Structure

2017 ◽  
Author(s):  
Tran Anh Vang ◽  
Xianmin Zhang ◽  
Benliang Zhu
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Single Crystal Silicon ◽  
High Sensitivity ◽  
Crystal Silicon ◽  
Nonlinearity Error ◽  
Trade Off ◽  
Design And Optimization ◽  
Piezoresistive Pressure Sensor ◽  
Piezoresistive Pressure Sensors

The sensitivity and linearity trade-off problem has become the hotly important issues in designing the piezoresistive pressure sensors. To solve these trade-off problems, this paper presents the design, optimization, fabrication, and experiment of a novel piezoresistive pressure sensor for micro pressure measurement based on a combined cross beam - membrane and peninsula (CBMP) structure diaphragm. Through using finite element method (FEM), the proposed sensor performances as well as comparisons with other sensor structures are simulated and analyzed. Compared with the cross beam-membrane (CBM) structure, the sensitivity of CBMP structure sensor is increased about 38.7 % and nonlinearity error is reduced nearly 8%. In comparison with the peninsula structure, the maximum non-linearity error of CBMP sensor is decreased about 40% and the maximum deflection is extremely reduced 73%. Besides, the proposed sensor fabrication is performed on the n-type single crystal silicon wafer. The experimental results of the fabricated sensor with CBMP membrane has a high sensitivity of 23.4 mV/kPa and a low non-linearity of −0.53% FSS in the pressure range 0–10 kPa at the room temperature. According to the excellent performance, the sensor can be applied to measure micro-pressure lower than 10 kPa.

scholarly journals Investigation of High Sensitivity Piezoresistive Pressure Sensors for -0.5…+0.5 kPa

2021 ◽  
Author(s):  
Mikhail ◽  
Denis Prigodskiy
Keyword(s):  
Automotive Industry ◽  
Pressure Sensor ◽  
Thermal Hysteresis ◽  
Pressure Sensors ◽  
High Sensitivity ◽  
Burst Pressure ◽  
Average Sensitivity ◽  
Optimum Geometry ◽  
Developed Pressure ◽  
Piezoresistive Pressure Sensors

The investigation of the pressure sensor chip's design developed for operation in ultralow differential pressure ranges has been conducted. The optimum geometry of a diaphragm has been defined using available technological resources. The pressure sensor chip with an area of 6.15 × 6.15 mm has an average sensitivity S of 34.5 mV/ κPa/V at nonlinearity 2K NL = 0.81 %FS and thermal hysteresis up to 0.6 %FS was created. Owing to the chip connection with stop elements, the burst pressure reaches 450 κPa. The developed pressure sensor can be used in medicine, automotive industry and highly specialized scientific developments.

FEM Simulation of a Twin-Island Structure Chip in Piezoresistive Pressure Sensor

2011 ◽  
Vol 464 ◽  
pp. 208-212
Author(s):  
Hai Bin Pan ◽  
Jian Ning Ding ◽  
Guang Gui Cheng ◽  
Hui Juan Fan
Keyword(s):  
Finite Element ◽  
Pressure Sensor ◽  
Pressure Sensors ◽  
Fem Simulation ◽  
Sensor Chip ◽  
Stress Distributions ◽  
Island Structure ◽  
Piezoresistive Pressure Sensor ◽  
Mems Technology ◽  
Piezoresistive Pressure Sensors

In this paper a twin-island structure in piezoresistive pressure sensor based on MEMS technology has been presented, and a finite element mechanical model has been developed to simulate the static mechanical behavior of this twin-island structure sensor chip, especially the stress distributions in diaphragm of the sensor chip, which has a vital significance on piezoresistive pressure sensors’ sensitivity. The possible impacts of twin-island’s location and twin-island’s width on the stress distributions, as well as the maximum value of compressive stress and tensile stress, have been investigated based on numerical simulation with Finite Element Method (FEM). The simulation results show that twin-island’s location has great effect on the stress distributions in sensor chips’ diaphragms and the sensitivity of piezoresistive pressure sensors, compared with the twin-island’s width.

SIMULATION METHODS OF PIEZORESISTIVE PRESSURE SENSORS IN ORDER TO IMPROVE CONSISTENCY

2012 ◽  
Vol 27 (02) ◽  
pp. 1350011 ◽  
Author(s):  
ZHAOHUA ZHANG ◽  
TIANLING REN ◽  
RUIRUI HAN ◽  
LI YUAN ◽  
BO PANG
Keyword(s):  
Pressure Sensor ◽  
Pressure Sensors ◽  
Simulation Method ◽  
Test Results ◽  
Silicon Membrane ◽  
Element Analysis ◽  
Piezoresistive Pressure Sensor ◽  
Consistency Results ◽  
Good Consistency ◽  
Piezoresistive Pressure Sensors

It is important to realize good consistency among different device units on a big wafer. The bad product consistency results from the processing deviation which is hard to control. A novel simulation method to control and reduce the influence of processing deviation on the sensitivity of a piezoresistive pressure sensor is provided in this paper. Based on finite element analysis (FEA) and mathematical integration, the performance of the pressure sensors is simulated. The pressure sensors are designed and fabricated according to the simulation results. The test results confirm that this simulation method can help to design the pressure sensor very precisely. From the simulation and test results, we find that properly enlarging the size of the square silicon membrane can improve the devices consistency.

TCR of the Ni-Cr Thin Film Resistors Used in Piezoresistive Pressure Sensor

2011 ◽  
Vol 483 ◽  
pp. 735-739 ◽  
Author(s):  
Li Xiao ◽  
Li Dong Du ◽  
Zhan Zhao ◽  
Zhen Fang ◽  
Jing Xu
Keyword(s):  
Thin Film ◽  
Pressure Sensor ◽  
Pressure Sensors ◽  
Temperature Characteristic ◽  
Piezoresistive Pressure Sensor ◽  
Mems Technology ◽  
Thin Film Resistors ◽  
Metal Materials ◽  
Piezoresistive Pressure Sensors ◽  
Effect Of The Composition

In this paper, temperature characteristic of Ni-Cr thin film resistors is studied which have a low temperature drifting coefficient and used in a kind of metal piezoresistive pressure sensors based on MEMS technology. Normally, Ni-Cr alloys have a small temperature coefficient of resistance (TCR) compared with some other metal materials. But it depends on the composition of Ni and Cr in the alloy and on the annealing process under different temperature. Through the research of the effect of the composition of the alloy and annealing cycles, it is found that 50:50wt% Ni-Cr thin film has negative TCR and 80:20wt% NiCr thin film has positive TCR. Both of them have a small TCR and can improve the precision of piezoresistive pressure sensor.

Design and Simulation of Pressure Sensor for Ocean Depth Measurements

2013 ◽  
Vol 313-314 ◽  
pp. 666-670 ◽  
Author(s):  
K.J. Suja ◽  
Bhanu Pratap Chaudhary ◽  
Rama Komaragiri
Keyword(s):  
Pressure Sensor ◽  
Integrated Circuit ◽  
Output Voltage ◽  
Pressure Sensors ◽  
Micro Electro Mechanical System ◽  
Constant Thickness ◽  
Piezoresistive Pressure Sensor ◽  
Wide Pressure Range ◽  
Processing Techniques ◽  
Wide Pressure

MEMS (Micro Electro Mechanical System) are usually defined as highly miniaturized devices combining both electrical and mechanical components that are fabricated using integrated circuit batch processing techniques. Pressure sensors are usually manufactured using square or circular diaphragms of constant thickness in the order of few microns. In this work, a comparison between circular diaphragm and square diaphragm indicates that square diaphragm has better perspectives. A new method for designing diaphragm of the Piezoresistive pressure sensor for linearity over a wide pressure range (approximately double) is designed, simulated and compared with existing single diaphragm design with respect to diaphragm deflection and sensor output voltage.

scholarly journals Study on the Stability of the Electrical Connection of High-Temperature Pressure Sensor Based on the Piezoresistive Effect of P-Type SiC

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 216
Author(s):  
Yongwei Li ◽  
Ting Liang ◽  
Cheng Lei ◽  
Qiang Li ◽  
Zhiqiang Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Pressure Sensor ◽  
Pressure Sensors ◽  
Extreme Environment ◽  
Maximum Temperature ◽  
Piezoresistive Effect ◽  
Electrical Connection ◽  
Contact Stability ◽  
The Stability ◽  
P Type

In this study, a preparation method for the high-temperature pressure sensor based on the piezoresistive effect of p-type SiC is presented. The varistor with a positive trapezoidal shape was designed and etched innovatively to improve the contact stability between the metal and SiC varistor. Additionally, the excellent ohmic contact was formed by annealing at 950 °C between Ni/Al/Ni/Au and p-type SiC with a doping concentration of 1018cm−3. The aging sensor was tested for varistors in the air of 25 °C–600 °C. The resistance value of the varistors initially decreased and then increased with the increase of temperature and reached the minimum at ~450 °C. It could be calculated that the varistors at ~100 °C exhibited the maximum temperature coefficient of resistance (TCR) of ~−0.35%/°C. The above results indicated that the sensor had a stable electrical connection in the air environment of ≤600 °C. Finally, the encapsulated sensor was subjected to pressure/depressure tests at room temperature. The test results revealed that the sensor output sensitivity was approximately 1.09 mV/V/bar, which is better than other SiC pressure sensors. This study has a great significance for the test of mechanical parameters under the extreme environment of 600 °C.

scholarly journals Pressure Sensor with New Electrical Circuit Utilizing Bipolar Junction Transistor

2021 ◽  
Author(s):  
Mikhail
Keyword(s):  
Theoretical Model ◽  
Pressure Sensor ◽  
High Sensitivity ◽  
Wheatstone Bridge ◽  
Electrical Circuit ◽  
Sensor Chip ◽  
Chip Size ◽  
Junction Transistor ◽  
Developed Pressure ◽  
P Type

High sensitivity MEMS pressure sensor chip for different ranges (1 to 60 kPa) utilizing the novel electrical circuit of piezosensitive differential amplifier with negative feedback loop (PDA-NFL) is developed. Pressure sensor chip PDA-NFL utilizes two bipolar-junction transistors (BJT) with vertical n-p-n type structure (V-NPN) and eight piezoresistors (p-type). Both theoretical model of sensor response to pressure and temperature and experimental data are presented. Data confirms the applicability of theoretical model. Introduction of the amplifier allows for decreasing chip size while keeping the same sensitivity as a chip with classic Wheatstone bridge circuit.

Assembly and Testing of Surface Micromachined, Piezoresistive Polysilicon Pressure Sensors

1999 ◽  
Author(s):  
Todd F. Miller ◽  
David J. Monk ◽  
Gary O’Brien ◽  
William P. Eaton ◽  
James H. Smith
Keyword(s):  
Pressure Sensor ◽  
Microelectromechanical Systems ◽  
Pressure Sensors ◽  
Single Crystal Silicon ◽  
Surface Micromachining ◽  
Process Technology ◽  
Crystal Silicon ◽  
Noise Characteristics ◽  
Testing Techniques ◽  
Piezoresistive Pressure Sensors

Abstract Surface micromachining is becoming increasingly popular for microelectromechanical systems (MEMS) and a new application for this process technology is pressure sensors. Uncompensated surface micromachined piezoresistive pressure sensors were fabricated by Sandia National Labs (SNL). Motorola packaged and tested the sensors over pressure, temperature and in a typical circuit application for noise characteristics. A brief overview of surface micromachining related to pressure sensors is described in the report along with the packaging and testing techniques used. The electrical data found is presented in a comparative manner between the surface micromachined SNL piezoresistive polysilicon pressure sensor and a bulk micromachined Motorola piezoresistive single crystal silicon pressure sensor.

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