Page 8 - MEMS Mechanical Sensors

Contents vii

6.2.3 Pressure Sensor Types 121
6.3 Traditional Pressure Sensors 121
6.3.1 Manometer 121
6.3.2 Aneroid Barometers 122
6.3.3 Bourdon Tube 122
6.3.4 Vacuum Sensors 123
6.4 Diaphragm-Based Pressure Sensors 123
6.4.1 Analysis of Small Deflection Diaphragm 125
6.4.2 Medium Deflection Diaphragm Analysis 127
6.4.3 Membrane Analysis 127
6.4.4 Bossed Diaphragm Analysis 128
6.4.5 Corrugated Diaphragms 129
6.4.6 Traditional Diaphragm Transduction Mechanisms 129
6.5 MEMS Technology Pressure Sensors 130
6.5.1 Micromachined Silicon Diaphragms 130
6.5.2 Piezoresistive Pressure Sensors 132
6.5.3 Capacitive Pressure Sensors 137
6.5.4 Resonant Pressure Sensors 139
6.5.5 Other MEMS Pressure Sensing Techniques 142
6.6 Microphones 143
6.7 Conclusions 145
References 145
CHAPTER 7
Force and Torque Sensors 153
7.1 Introduction 153
7.2 Silicon-Based Devices 154
7.3 Resonant and SAW Devices 157
7.4 Optical Devices 159
7.5 Capacitive Devices 160
7.6 Magnetic Devices 162
7.7 Atomic Force Microscope and Scanning Probes 164
7.8 Tactile Sensors 166
7.9 Future Devices 168
References 168

CHAPTER 8
Inertial Sensors 173
8.1 Introduction 173
8.2 Micromachined Accelerometer 175
8.2.1 Principle of Operation 175
8.2.2 Research Prototype Micromachined Accelerometers 180
8.2.3 Commercial Micromachined Accelerometer 192
8.3 Micromachined Gyroscopes 195
8.3.1 Principle of Operation 195
8.3.2 Research Prototypes 199
8.3.3 Commercial Micromachined Gyroscopes 204