MEMS Piezo Pressure Sensor

Views:
 
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

Designing & Fabrications of Silicon MEMS Piezoresistive Pressure Sensor for Biomedical Applications Abdulmunaem ShanebMMEWashington State University : 

Fall2010 Designing & Fabrications of Silicon MEMS Piezoresistive Pressure Sensor for Biomedical Applications Abdulmunaem ShanebMMEWashington State University

How Piezoresistive Pressure Sensors Work? : 

1.Diaphragm : converts the pressure to mechanical stress. 2.Piezoresistor: converts the mechanical stress into resistance change. 3.Wheatstone bridge :converts the resistance change into output voltage . How Piezoresistive Pressure Sensors Work?

The sensitivity of Piezoresistive Pressure Sensors: : 

The sensitivity of Piezoresistive Pressure Sensors:

Applications & Specifications desired: : 

Applications & Specifications desired: Ventilators. Spirometers. Respirators Blood Pressure measurement. Applications: Specifications Thickness of diaphragm: 10µm-15µm Diameter of circular diaphragm & the side length of square diaphragm: 500µm-700µ Measure a pressure :0-1 bar Resolution :1 mbar Sensitivity : 30 mv/vbar

Slide 5: 

Design assumptions and conditions: 1. The diaphragm is flat and of uniform thickness (t). 2. Pressure is applied normally to the plane of diaphragm. 3. The effect of temperature on sensitivity is not considered in this project 4. The resistors are located at the rim of the diaphragm where the stress is very high . 5. The maximum deflection must not exceed 30% of the diaphragm thickness. 6. The thickness of diaphragm is not too thick (maximum 20% of diaphragm diameter or the side length for the square diaphragm). 7. The elastic limit of the material is not exceeded (tensile strain less than 0.7GPa).

Designing calculation : 

Designing calculation

Slide 7: 

1. An IC Piezoresistive Pressure Sensor for Biomedical Instrumentation. Samaun, Kensall D.Wise , and James B. Angell. 1972 2. Robust Design of Silicon Peizoresistive Pressure Sensor. Tai-Kang Shing . 3. A Simulation program for the sensitivity and linearity of piezoresistive pressure sensor.Liwie Lin,Huey- Chi Chu and Yen-WenLu. Dec. 1999. 4. Mechanical Characterization of Single Crystal Silicon and UV-LIGA Nickel Thin Films Using Tensile Tester Operated in AFM. Y. LEE, J. TADA and Y. ISONO. Oct 2004. 5. A Silicon Piezoresistor Pressure Sensor. Ranjit Singh, Low Lee Ngo, Ho Soon Seng, and Frederick Neo 6. Theory of Plates and Shells. S.Temoshinco and S.Woinowsky-Krieger.1987 7. MEMS Mechanical Sensors. Stephen Beeby, Graham Ensell, Michael Kraft, and Neil White 2004 7. Analysis and Design Principles of MEMS Devices. Minhang Bao. 2005. 8. Foundation of MEMS. Chang Liu. 2006 References:

authorStream Live Help