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| Preface to Second Edition | |
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| Preface to First Edition | |
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| Note to Instructors | |
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| About the Author | |
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| Notational Conventions | |
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| Introduction | |
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| Preview | |
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| The History of MEMS Development | |
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| From the Beginning to 1990 | |
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| From 1990 to 2001 | |
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| 2002 to present | |
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| Future Trends | |
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| The Intrinsic Characteristics of MEMS | |
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| Miniaturization | |
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| Microelectronics Integration | |
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| Parallel Fabrication with Precision | |
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| Devices: Sensors and Actuators | |
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| Energy Domains and Transducers | |
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| Sensors Considerations | |
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| Sensor Noise and Design Complexity | |
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| Actuators Considerations | |
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| Summary | |
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| Problems | |
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| References | |
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| First-Pass Introduction to Microfabrication | |
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| Preview | |
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| Overview of Microfabrication | |
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| Essential Overview of Frequently Used Microfabrication Processes | |
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| Photolithography | |
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| Thin film deposition | |
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| Thermal oxidation of silicon | |
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| Wet Etching | |
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| Silicon anisotropic etching | |
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| Plasma etching and reactive ion etching | |
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| Doping | |
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| Wafer dicing | |
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| Wafer bonding | |
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| The Microelectronics Fabrication Process Flow | |
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| Silicon-based MEMS Processes | |
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| Packaging and Integration | |
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| Integration Options | |
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| Encapsulation | |
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| New Materials and Fabrication Processes | |
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| Process Selection and Design | |
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| Points of Consideration for Deposition Processes | |
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| Points of Consideration for Etching Processes | |
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| Ideal Rules for Building a Process Flow | |
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| Rules for Building a Robust Process | |
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| Summary | |
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| Problems | |
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| References | |
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| Review of Essential Electrical and Mechanical Concepts | |
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| Preview | |
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| Conductivity of Semiconductors | |
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| Semiconductor Materials | |
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| Calculation of Charge Carrier Concentration | |
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| Conductivity and Resistivity | |
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| Crystal Planes and Orientations | |
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| Stress and Strain | |
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| Internal Force Analysis: Newton's Laws of Motion | |
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| Definitions of Stress and Strain | |
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| General Scalar Relation between Tensile Stress and Strain | |
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| Mechanical Properties of Silicon and Related Thin Films | |
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| General Stress Strain Relations | |
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| Flexural Beam Bending Analysis under Simple Loading Conditions | |
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| Types of Beams | |
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| Longitudinal Strain under Pure Bending | |
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| Deflection of Beams | |
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| Finding the Spring Constants | |
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| Torsional Deflections | |
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| Intrinsic Stress | |
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| Dynamic System, Resonant Frequency, and Quality Factor | |
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| Dynamic System and Governing Equation | |
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| Response under Sinusoidal Resonant Input | |
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| Damping and Quality Factor | |
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| Resonant Frequency and Bandwidth | |
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| Active Tuning of Spring Constant and Resonant Frequency | |
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| A List of Suggested Courses and Books | |
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| Summary | |
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| Problems | |
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| References | |
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| Electrostatic Sensing and Actuation | |
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| Preview | |
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| Introduction to Electrostatic Sensors and Actuators | |
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| Parallel Plate Capacitor | |
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| Capacitance of Parallel Plates | |
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| Equilibrium Position of Electrostatic Actuator under Bias | |
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| Pull-in Effect of Parallel-Plate Actuators | |
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| Applications of Parallel-Plate Capacitors | |
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| Inertia Sensor | |
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| Pressure Sensor | |
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| Flow Sensor | |
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| Tactile sensor | |
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| Parallel-plate actuators | |
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| Interdigitated Finger Capacitors | |
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| Applications of Comb-Drive Devices | |
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| Inertia Sensors | |
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| Actuators | |
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| Summary | |
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| Problems | |
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| References | |
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| Thermal Sensing and Actuation | |
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| Preview | |
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| Introduction | |
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| Thermal Sensors | |
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| Thermal Actuators | |
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| Fundamentals of Thermal Transfer | |
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| Sensors and Actuators Based on Thermal Expansion | |
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| Thermal Bimorph Principle | |
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| Thermal Actuators with a Single Material | |
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| Thermal Couples | |
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| Thermal Resistors | |
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| Applications | |
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| Inertia Sensors | |
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| Flow Sensors | |
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| Infrared Sensors | |
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| Other Sensors | |
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| Summary | |
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| Problems | |
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| References | |
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| Piezoresistive Sensors | |
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| Preview | |
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| Origin and Expression of Piezoresistivity | |
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| Piezoresistive Sensor Materials | |
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| Metal Strain Gauges | |
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| Single Crystal Silicon | |
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| Polycrystalline Silicon | |
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| Stress Analysis of Mechanical Elements | |
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| Stress in Flexural Cantilevers | |
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| Stress and Deformation in Membrane | |
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| Applications of Piezoresistive Sensors | |
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| Inertial Sensors | |
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| Pressure Sensors | |
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| Tactile sensor | |
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| Flow sensor | |
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| Summary | |
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| Problems | |
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| References | |
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| Piezoelectric Sensing and Actuation | |
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| Preview | |
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| Introduction | |
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| Background | |
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| Mathematical description of piezoelectric effects | |
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| Cantilever piezoelectric actuator model | |
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| Properties of Piezoelectric Materials | |
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| Quartz | |
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| PZT | |
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| PVDF | |
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| ZnO | |
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| Other Materials | |
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| Applications | |
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| Inertia Sensors | |
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| Acoustic Sensors | |
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| Tactile Sensors | |
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| Flow Sensors | |
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| Surface Elastic Waves | |
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| Summary | |
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| Problems | |
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| References | |
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| Magnetic Actuation | |
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| Preview | |
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| Essential Concepts and Principles | |
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| Magnetization and Nomenclatures | |
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| Selected Principles of Micro Magnetic Actuators | |
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| Fabrication of Micro Magnetic Components | |
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| Deposition of Magnetic Materials | |
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| Design and Fabrication of Magnetic Coil | |
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| Case Studies of MEMS Magnetic Actuators | |
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| Summary | |
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| Problems | |
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| References | |
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| Summary of Sensing and Actuation Methods | |
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| Preview | |
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| Comparison of Major Sensing and Actuation Methods | |
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| Other Sensing and Actuation Methods | |
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| Tunneling Sensing | |
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| Optical Sensing | |
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| Field Effect Transistors | |
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| Radio Frequency Resonance Sensing | |
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| Summary | |
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| Problems | |
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| References | |
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| Bulk Micromachining and Silicon Anisotropic Etching | |
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| Preview | |
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| Introduction | |
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| Anisotropic Wet Etching | |
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| Introduction | |
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| Rules of Anisotropic Etching���Simplest Case | |
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| Rules of Anisotropic Etching���Complex Structures | |
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| Forming Protrusions | |
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| Interaction of Etching Profiles from Isolated Patterns | |
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| Summary of design methodology | |
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| Chemicals for Wet Anisotropic Etching | |
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| Dry Etching and Deep Reactive Ion Etching | |
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| Isotropic Wet Etching | |
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| Gas Phase Etchants | |
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| Native Oxide | |
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| Special Wafers and Techniques | |
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| Summary | |
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| Problems | |
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| References | |
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| Surface Micromachining | |
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| Preview | |
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| Basic Surface Micromachining Processes | |
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| Sacrificial Etching Process | |
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| Micro Motor Fabrication Process���A First Pass | |
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| Micro Motor Fabrication Process���A Second Pass | |
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| Micro Motor Fabrication Process���Third Pass | |
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| Structural and Sacrificial Materials | |
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| Material Selection Criteria for a Two-layer Process | |
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| Thin Films by Low Pressure Chemical Vapor Deposition | |
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| Other Surface Micromachining Materials and Processes | |
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| Acceleration of Sacrificial Etch | |
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| Stiction and Anti-stiction Methods | |
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| Summary | |
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| Problems | |
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| References | |
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| Process Synthesis: Putting It all Together | |
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| Preview | |
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| Process for Suspension Beams | |
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| Process for Membranes | |
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| Process for Cantilevers | |
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| SPM Technologies Case Motivation | |
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| General Fabrication Methods for Tips | |
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| Cantilevers with Integrated Tips | |
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| Cantilevers with Integrated Sensors | |
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| SPM Probes with Actuators | |
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| Practical Factors Affecting Yield of MEMS | |
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| Summary | |
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| Problems | |
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| References | |
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| Polymer MEMS | |
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| Preview | |
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| Introduction | |
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| Polymers in MEMS | |
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| Polyimide | |
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| SU-8 | |
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| Liquid Crystal Polymer (LCP) | |
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| PDMS | |
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| PMMA | |
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| Parylene | |
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| Fluorocarbon | |
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| Other Polymers | |
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| Representative Applications | |
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| Acceleration Sensors | |
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| Pressure Sensors | |
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| Flow sensors | |
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| Tactile Sensors | |
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| Summary | |
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| Problems | |
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| Reference | |
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| Micro Fluidics Applications | |
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| Preview | |
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| Motivation for Microfluidics | |
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| Essential Biology Concepts | |
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| Basic Fluid Mechanics Concepts | |
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| The Reynolds Number and Viscosity | |
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| Methods for Fluid Movement in Channels | |
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| Pressure Driven Flow | |
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| Electrokinetic Flow | |
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| Electrophoresis and Dielectrophoresis | |
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| Design and Fabrication of Selective Components | |
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| Channels | |
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| Valves | |
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| Summary | |
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| Problems | |
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| References | |
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| Case Studies of Selected MEMS Products | |
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| Preview | |
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| Case Studies: Blood Pressure (BP) Sensor | |
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| Background and History | |
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| Device Design Considerations | |
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| Commercial Case: NovaSensor BP Sensor | |
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| Case Studies: Microphone | |
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| Background and History | |
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| Design Considerations | |
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| Commercial Case: Knowles Microphone | |
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| Case Studies: Acceleration Sensors | |
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| Background and History | |
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| Design Considerations | |
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| Commercial Case: Analog Devices and MEMSIC | |
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| Case Studies: Gyros | |
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| Background and History | |
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| The Coriolis Force | |
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| MEMS Gyro Design | |
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| Single Axis Gyro Dynamics | |
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| Commercial Case: InvenSense Gyro | |
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| Summary of Top Concerns for MEMS Product Development | |
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| Performance and Accuracy | |
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| Repeatability and Reliability | |
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| Managing the Cost of MEMS Products | |
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| Market Uncertainties, Investment, and Competition | |
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| Summary | |
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| Problems | |
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| References | |
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| Characteristics of selected MEMS material | |
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| Frequently Used Formula for Beams, Cantilevers, and Plates | |
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| Basic Tools for Dealing with a Mechanical Second-order Dynamic System | |
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| Most Commonly Encountered Materials | |
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| Most Commonly Encountered Material Removal Process Steps | |
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| A List of General Compatibility between General Materials and Processes | |
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| Comparison of Commercial Inertial Sensors | |
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| Answers to selected problems | |
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| Index | |