Fundamentals and Applications of Microfluidics

512 Pages·2012·6.85 MB·English

Fundamentals and Applications
of Microfluidics
Second Edition
For a complete listing of recent titles
in theArtech House Integrated Microsystems Series,
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Fundamentals and Applications
of Microfluidics
Second Edition
Nam-Trung Nguyen
Steven T. Wereley
artechhouse.com
Library of Congress Cataloging-in-Publication Data
Nguyen, Nam-Trung, 1970–
Fundamentals and applications of microfluidics/Nam-Trung Nguyen, Steve Wereley.
—2nd ed.
p. cm.—(Artech House integrated microsystems series)
Includes bibliographical references and index.
ISBN 1-58053-972-6 (alk. paper)
1. Fluidic devices. 2. Microfluidics. 3. Microeletromechanical systems.
I. Wereley, Steven T. II. Title. III. Series: Integrated microsystems series.
TJ853.N48 2006
620.1’06—dc22 2006045969
British Library Cataloguing in Publication Data
Nguyen, Nam-Trung, 1970–
Fundamentals and applications of microfluidics.—2nd ed.—
(Artech House integrated microsystems series)
1. Fluidic devices 2. Micromechanics
I. Title II. Wereley, Steven T.
620.1'06
ISBN-10 1-58053-972-6
ISBN-13 978-1-58053-972-2
Cover design by Igor Valdman
© 2006 ARTECH HOUSE, INC.
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10 9 8 7 6 5 4 3 2 1
DedicationTo my wife, Jill—my friend, my companion,
and the love of my life
To our daughter Kristi, our son-in-law Bill,
and our two beautiful granddaughters, Megan and Apryl
Contents
Preface xi
Acknowledgments xiii
Chapter1 Introduction 1
1.1 WhatIsMicrofluidics? 1
1.1.1 RelationshipsAmongMEMS,Nanotechnology,andMicrofluidics 1
1.1.2 CommercialAspects 4
1.1.3 ScientificAspects 5
1.2 MilestonesofMicrofluidics 6
1.2.1 DeviceDevelopment 6
1.2.2 TechnologyDevelopment 8
1.3 OrganizationoftheBook 8
References 9
Chapter2 FluidMechanicsTheory 11
2.1 Introduction 11
2.1.1 IntermolecularForces 12
2.1.2 TheThreeStatesofMatter 14
2.1.3 ContinuumAssumption 15
2.2 ContinuumFluidMechanicsatSmallScales 18
2.2.1 GasFlows 19
2.2.2 LiquidFlows 23
2.2.3 BoundaryConditions 25
2.2.4 ParallelFlows 30
2.2.5 LowReynoldsNumberFlows 33
2.2.6 EntranceEffects 36
2.2.7 SurfaceTension 37
2.3 MolecularApproaches 39
2.3.1 MD 40
2.3.2 DSMCTechnique 42
2.4 Electrokinetics 44
2.4.1 Electro-osmosis 44
2.4.2 Electrophoresis 47
2.4.3 Dielectrophoresis 49
2.5 Conclusion 51
v
vi FundamentalsandApplicationsofMicrofluidics
Problems 52
References 53
Chapter3 FabricationTechniquesforMicrofluidics 55
3.1 BasicMicrotechniques 55
3.1.1 Photolithography 55
3.1.2 AdditiveTechniques 57
3.1.3 SubtractiveTechniques 59
3.1.4 PatternTransferTechniques 61
3.2 FunctionalMaterials 62
3.2.1 MaterialsRelatedtoSiliconTechnology 62
3.2.2 Polymers 67
3.3 Silicon-BasedMicromachiningTechniques 69
3.3.1 SiliconBulkMicromachining 69
3.3.2 SiliconSurfaceMicromachining 76
3.4 Polymer-BasedMicromachiningTechniques 81
3.4.1 ThickResistLithography 82
3.4.2 PolymericBulkMicromachining 86
3.4.3 PolymericSurfaceMicromachining 87
3.4.4 MicrostereoLithography 91
3.4.5 Micromolding 95
3.5 OtherMicromachiningTechniques 100
3.5.1 SubtractiveTechniques 101
3.5.2 AdditiveTechniques 103
3.6 AssemblyandPackagingofMicrofluidicDevices 104
3.6.1 WaferLevelAssemblyandPackaging 104
3.6.2 DeviceLevelPackaging 106
3.7 Biocompatibility 108
3.7.1 MaterialResponse 108
3.7.2 TissueandCellularResponse 109
3.7.3 BiocompatibilityTests 109
Problems 109
References 110
Chapter4 ExperimentalFlowCharacterization 117
4.1 Introduction 117
4.1.1 PointwiseMethods 117
4.1.2 Full-FieldMethods 118
4.2 OverviewofµPIV 122
4.2.1 FundamentalPhysicsConsiderationsofµPIV 122
4.2.2 SpecialProcessingMethodsforµPIVRecordings 138
4.2.3 AdvancedProcessingMethodsSuitableforBothMicro/Macro-PIV
Recordings 141
4.3 µPIVExamples 144
4.3.1 FlowinaMicrochannel 144
4.3.2 FlowinaMicronozzle 146
4.3.3 FlowAroundaBloodCell 149
4.3.4 FlowinMicrofluidicBiochip 151
4.3.5 Conclusions 153
4.4 ExtensionsoftheµPIVTechnique 153
Contents vii
4.4.1 MicrofluidicNanoscope 153
4.4.2 MicroparticleImageThermometry 158
4.4.3 InfraredµPIV 167
4.4.4 ParticleTrackingVelocimetry 169
Problems 172
References 172
Chapter5 MicrofluidicsforExternalFlowControl 177
5.1 VelocityandTurbulenceMeasurement 177
5.1.1 VelocitySensors 177
5.1.2 ShearStressSensors 181
5.2 TurbulenceControl 189
5.2.1 Microflaps 190
5.2.2 Microballoon 191
5.2.3 MicrosyntheticJet 192
5.3 MicroairVehicles 193
5.3.1 Fixed-WingMAV 194
5.3.2 Flapping-WingMAV 195
5.3.3 Microrotorcraft 197
5.3.4 Microrockets 198
Problems 207
References 208
Chapter6 MicrofluidicsforInternalFlowControl:Microvalves 211
6.1 DesignConsiderations 213
6.1.1 Actuators 213
6.1.2 ValveSpring 234
6.1.3 ValveSeat 237
6.1.4 PressureCompensationDesign 238
6.2 DesignExamples 239
6.2.1 PneumaticValves 239
6.2.2 ThermopneumaticValves 240
6.2.3 ThermomechanicalValves 242
6.2.4 PiezoelectricValves 244
6.2.5 ElectrostaticValves 245
6.2.6 ElectromagneticValves 247
6.2.7 ElectrochemicalandChemicalValves 248
6.2.8 Capillary-ForceValves 250
6.3 Summary 250
Problems 251
References 251
Chapter7 MicrofluidicsforInternalFlowControl:Micropumps 255
7.1 DesignConsiderations 256
7.1.1 MechanicalPumps 256
7.1.2 NonmechanicalPumps 269
7.2 DesignExamples 288
7.2.1 MechanicalPumps 288
7.2.2 NonmechanicalPumps 298
7.3 Summary 303
viii FundamentalsandApplicationsofMicrofluidics
Problems 303
References 304
Chapter8 MicrofluidicsforInternalFlowControl:MicroflowSensors 311
8.1 DesignConsiderations 311
8.1.1 DesignParameters 311
8.1.2 NonthermalFlowSensors 312
8.1.3 ThermalFlowSensors 317
8.2 DesignExamples 324
8.2.1 NonthermalFlowSensors 324
8.2.2 ThermalFlowSensors 327
8.3 Summary 335
Problems 336
References 336
Chapter9 MicrofluidicsforLifeSciencesandChemistry:Microneedles 339
9.1 DesignConsiderations 341
9.1.1 MechanicalDesign 341
9.1.2 DeliveryModes 346
9.2 DesignExamples 348
9.2.1 SolidMicroneedles 348
9.2.2 HollowMicroneedles 349
9.3 Summary 352
Problems 353
References 353
Chapter10 MicrofluidicsforLifeSciencesandChemistry:Micromixers 357
10.1 DesignConsiderations 359
10.1.1 ParallelLamination 360
10.1.2 SequentialLamination 363
10.1.3 SequentialSegmentation 364
10.1.4 SegmentationBasedonInjection 366
10.1.5 FocusingofMixingStreams 369
10.1.6 FormationofDropletsandChaoticAdvection 372
10.2 DesignExamples 374
10.2.1 PassiveMicromixers 374
10.2.2 ActiveMicromixers 383
10.3 Summary 386
Problems 388
References 389
Chapter11 MicrofluidicsforLifeSciencesandChemistry:Microdispensers 395
11.1 DesignConsiderations 395
11.1.1 DropletDispensers 395
11.1.2 In-ChannelDispensers 404
11.2 DesignExamples 408
11.2.1 DropletDispensers 408
11.2.2 In-ChannelDispensers 412
11.3 Summary 414
Problems 415