MEMSAND MICROSYSTEMS Design, Manufacture, and Nanoscale Engineering

Transcription

1 MEMSAND MICROSYSTEMS Design, Manufacture, and Nanoscale Engineering Second Edition TAI-RAN HSU Microsystems Design and Packaging Laboratory Department of Mechanical and Aerospace Engineering San Jose State University WILEY JOHN WILEY & SONS, INC.

2 PREFACE PREFACE TO THE FIRST EDITION SUGGESTIONS TO INSTRUCTORS xvii xix xxiii OVERVIEW OF MEMS AND MICROSYSTEMS MEMS and Microsystems / Typical MEMS and Microsystems Products / Microgears / Micromotors / Microturbines / Micro-Optical Components / Evolution of Microfabrication / Microsystems and Microelectronics / Multidisciplinary Nature of Microsystems Design and Manufacture / Microsystems and Miniaturization / Application of Microsystems in Automotive Industry / Safety / Engine and Power Trains / Comfort and Convenience / Vehicle Diagnostics and Health Monitoring / Future Automotive Applications / Application of Microsystems in Other Industries / 27 vii

3 viii CONTENTS Application in Health Care Industry / Application in Aerospace Industry / Application in Industrial Products / Application in Consumer Products / Application in Telecommunications / Markets for Microsystems / 30 Problems / 32 WORKING PRINCIPLES OF MICROSYSTEMS Introduction / Microsensors / Acoustic Wave Sensors / Biomedical and Biosensors / Chemical Sensors / Optical Sensors / Pressure Sensors / Thermal Sensors / Microactuation / Actuation Using Thermal Forces / Actuation Using Shape Memory Alloys / Actuation Using Piezoelectric Effect / Actuation Using Electrostatic Forces / MEMS with Microactuators / Microgrippers / Miniature Microphones / Micromotors / Microactuators with Mechanical Inertia / Microaccelerometers / Microgyroscopes / Microfluidics / Microvalves / Micropumps / Micro-Heat Pipes / 75 Problems / 77 ENGINEERING SCIENCE FOR MICROSYSTEMS DESIGN AND FABRICATION Introduction / Atomic Structure of Matter / 83

4 3.3 Ions and Ionization / Molecular Theory of Matter and Intermolecular Forces / Doping of Semiconductors / Diffusion Process / Plasma Physics / Electrochemistry / Electrolysis / Electrohydrodynamics / 102 Problems / 105 ENGINEERING MECHANICS FOR MICROSYSTEMS DESIGN Introduction / Static Bending of Thin Plates / Bending of Circular Plates with Edge Fixed / Bending of Rectangular Plates with All Edges Fixed / Bending of Square Plates with Edges Fixed / Mechanical Vibration / General Formulation / Resonant Vibration / Microaccelerometers / Design Theory of Accelerometers / Damping Coefficients / Resonant Microsensors / Thermomechanics / Thermal Effects on Mechanical Strength of Materials / Creep Deformation / Thermal Stresses / Fracture Mechanics / Stress Intensity Factors / Fracture Toughness / Interfacial Fracture Mechanics / Thin-Film Mechanics / Overview of Finite Element Stress Analysis / The Principle / Engineering Applications / Input Information to FEA / 175

5 4.7.4 Output from FEA / Graphical Output / General Remarks / 176 Problems / THERMOFLUID ENGINEERING AND MICROSYSTEMS DESIGN Introduction / Overview of Basics of Fluid Mechanics at Macro- and Mesoscales / Viscosity of Fluids / Streamlines and Stream Tubes / Control Volumes and Control Surfaces / Flow Patterns and Reynolds Number / Basic Equations in Continuum Fluid Dynamics / Continuity Equation / Momentum Equation / Equation of Motion / Laminar Fluid Flow in Circular Conduits / Computational Fluid Dynamics / Incompressible Fluid Flow in Microconduits / Surface Tension / Capillary Effect / Micropumping / Overview of Heat Conduction in Solids / General Principle of Heat Conduction / Fourier Law of Heat Conduction / Heat Conduction Equation / Newton's Cooling Law / Solid-Fluid Interaction / Boundary Conditions / Heat Conduction in Multilayered Thin Films / Heat Conduction in Solids at Submicrometer Scale / 220 Problems / SCALING LAWS IN MINIATURIZATION Introduction to Scaling / Scaling in Geometry / 228

6 Xi 6.3 Scaling in Rigid-Body Dynamics / Scaling in Dynamic Forces / Trimmer Force Scaling Vector / Scaling in Electrostatic Forces / Scaling of Electromagnetic Forces / Scaling in Electricity / Scaling in Fluid Mechanics / Scaling in Heat Transfer / Scaling in Heat Conduction / Scaling in Heat Convection / 243 Problems / MATERIALS FOR MEMS AND MICROSYSTEMS Introduction / Substrates and Wafers / Active Substrate Materials / Silicon as Substrate Material / Ideal Substrate for MEMS / Single-Crystal Silicon and Wafers / Crystal Structure / Miller Indices / Mechanical Properties of Silicon / Silicon Compounds / Silicon Dioxide / Silicon Carbide / Silicon Nitride / Polycrystalline Silicon / Silicon Piezoresistors / Gallium Arsenide / Quartz / Piezoelectric Crystals / Polymers / Polymers as Industrial Materials / Polymers for MEMS and Microsystems / Conductive Polymers / Langmuir-Blodgett Film / SU-8 Photoresists / Packaging Materials / 280 Problems / 281

7 8 MICROSYSTEMS FABRICATION PROCESSES Introduction / Photolithography / Overview / Photoresists and Application / Light Sources / Photoresist Development / Photoresist Removal and Postbaking / Ion Implantation / Diffusion / Oxidation / Thermal Oxidation / Silicon Dioxide / Thermal Oxidation Rates / Oxide Thickness by Color / Chemical Vapor Deposition / Working Principle of CVD / Chemical Reactions in CVD / Rate of Deposition / Enhanced CVD / Physical Vapor Deposition: Sputtering / Deposition by Epitaxy / Etching / Chemical Etching / Plasma Etching / Summary of Microfabrication / 317 Problems / OVERVIEW OF MICROMANUFACTURING Introduction / Bulk Micromanufacturing / Overview of Etching / Isotropie and Anisotropie Etching / Wet Etchants / Etch Stop / Dry Etching / Comparison of Wet versus Dry Etching / Surface Micromachining / Description / 333

8 XÜi Process / Mechanical Problems Associated with Surface Micromachining / LIGA Process / Description / Materials for Substrates and Photoresists / Electroplating / SLIGA Process / Summary of Micromanufacturing / Bulk Micromanufacturing / Surface Micromachining / LIGA Process / 343 Problems / MICROSYSTEMS DESIGN Introduction / Design Considerations / Design Constraints / Selection of Materials / Selection of Manufacturing Processes / Selection of Signal Transduction / Electromechanical System / Packaging / Process Design / Photolifhography / Thin-Film Fabrications / Geometry Shaping / Mechanical Design / Geometry of MEMS Components / Thermomechanical Loading / Thermomechanical Stress Analysis / Dynamic Analysis / Interfacial Fracture Analysis / Mechanical Design Using Finite Element Method / Finite Element Formulation / Simulation of Microfabrication Processes / Design of Silicon Die of a Micropressure Sensor / Design of Microfluidic Network Systems / Fluid Resistance in Microchannels / 383

9 Capillary Electrophoresis Network Systems / Mathematical Modeling of Capillary Electrophoresis Network Systems / Design Case: Capillary Electrophoresis Network System / Capillary Electrophoresis in Curved Channels / Issues in Design of CE Processes / Computer-Aided Design / Why CAD? / What Is in a CAD Package for Microsystems? / How to Choose a CAD Package / Design Case Using CAD / 398 Problems / ASSEMBLY, PACKAGING, AND TESTING OF MICROSYSTEMS Introduction / Overview of Microassembly / High Costs of Microassembly / Microassembly Processes / Major Technical Problems in Microassembly / Tolerances in Microassembly / Tools and Fixtures / Contact Problems in Microassembly Tools / Microassembly Work Cells / Challenging Issues in Microassembly / Overview of Microsystems Packaging / General Considerations in Packaging Design / Three Levels of Microsystems Packaging / Die-Level Packaging / Device-Level Packaging / System-Level Packaging / Interfaces in Microsystems Packaging / Essential Packaging Technologies / Die Preparation / Surface Bonding / Adhesives / Eutectic Bonding / Anodic Bonding / Silicon Fusion Bonding / Overview of Surface Bonding Techniques / 434

10 Silicon-on-Insulator: Special Surface Bonding Techniques / Wire Bonding / Sealing and Encapsulation / Integrated Encapsulation Processes / Sealing by Wafer Bonding / Vacuum Sealing and Encapsulation / Three-Dimensional Packaging / Selection of Packaging Materials / Signal Mapping and Transduction / Typical Electrical Signals in Microsystems / Measurement of Resistance / Signal Mapping and Transduction in Pressure Sensors / Capacitance Measurements / Design Case on Pressure Sensor Packaging / Reliability in MEMS Packaging / Testing for Reliability / 456 Problems / 458 INTRODUCTION TO NANOSCALE ENGINEERING Introduction / Micro- and Nanoscale Technologies / General Principle of Nanofabrication / Nanoproducts / Application of Nanoproducts / Quantum Physics / Molecular Dynamics / Fluid Flow in Submicrometer- and Nanoscales / RarefiedGas / Knudsen and Mach Numbers / Modeling of Micro- and Nanoscale Gas Flow / Heat Conduction at Nanoscale / Heat Transmission at Submicrometer- and Nanoscale / Thermal Conductivity of Thin Films / Heat Conduction Equation for Thin Films / Measurement of Thermal Conductivity / Challenges in Nanoscale Engineering / Nanopatterning in Nanofabrication / Nanoassembly / 500

11 New Materials for Nanoelectromechamcal Systems (NEMS) / Analytical Modeling / Testing / Social Impacts of Nanoscale Engineering / 502 Problems / 503 REFERENCES 509 APPENDIX 1 RECOMMENDED UNITS FOR THERMOPHYSICAL QUANTITIES 523 APPENDIX 2 CONVERSION OF UNITS 525 INDEX 527