Table Of ContentNanoelectronic
Devices
TThhiiss ppaaggee iinntteennttiioonnaallllyy lleefftt bbllaannkk
Byung-Gook Park
Sung Woo Hwang
Young June Park
Nanoelectronic
Devices
CRC Press
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Version Date: 20120120
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December2,2011 10:53 PSPBook-9inx6in 00-Hwang–prelims
Contents
Preface xi
1 QuantumMechanicsforNanoelectronicDevices 1
1.1 FundamentalConceptsofQuantumMechanics 1
1.1.1 WaveNatureofParticles 1
1.1.2 WaveFunctionsandOperators 6
1.1.3 Schro¨dinger’sWaveEquation 8
1.1.4 MeaningoftheWaveFunction 10
1.1.5 ElectroninaBox 11
1.2 SolidStateandEnergyBands 14
1.2.1 ElectronWavesandEnergyLevelsinAtoms 14
1.2.2 NumericalExperimentswithQuantumWell
Model 21
1.2.3 FormationofSolidsandEnergyBands 25
1.3 EnergyBandsandElectricalProperties 29
1.3.1 WaveFunctionAnalysisandEnvelope
Functions 29
1.3.2 BlochTheorem 31
1.3.3 WaveVectorsandk-Space 32
1.3.4 BraggReflectionandBrillouinZones 34
1.3.5 Energy-versus-kDiagraminOne-Dimensional
Space 37
1.3.6 Energy-versus-kDiagramin
Three-DimensionalSpace 41
1.3.7 EnergyBandandClassificationofSolidsby
ElectricalConduction 44
1.3.8 SemiclassicalEquationsofMotionfor
Electrons 44
1.3.9 EffectiveMass 46
December2,2011 10:53 PSPBook-9inx6in 00-Hwang–prelims
vi Contents
1.3.10ConceptofHoles 47
1.4 NanostructureApplicationsofQuantumMechanics 49
1.4.1 DensityofStatesforElectronsina
MacroscopicBox 49
1.4.2 ConfinementandDensityofStatesinLower
Dimensions 51
1.4.3 Tunneling 59
2 ElectronTransportandDevicePhysics 67
2.1 SemiconductorsandCarriers 67
2.1.1 StrategyfortheCalculationofCarrier
Concentration 67
2.1.2 DensityofStatesinSemiconductors 68
2.1.3 Fermi–DiracDistribution 69
2.1.4 ElectronandHoleConcentrations 72
2.1.5 IntrinsicSemiconductors 75
2.1.6 CarriersinExtrinsicSemiconductors 77
2.1.7 PositionoftheFermiLevel 81
2.2 CarrierTransport 83
2.2.1 DriftofCarriers 83
2.2.2 DiffusionofCarriers 85
2.2.3 TotalCurrentinSemiconductors 87
2.2.4 InvarianceofFermiLevelinEquilibrium 88
2.2.5 Non-UniformDoping 90
2.2.6 EinsteinRelations 92
2.3 Generation,Recombination,andContinuity 93
2.3.1 GenerationandRecombinationMechanisms 93
2.3.2 ExcessCarriersandRecombination 94
2.3.3 CarrierGenerationandQuasi-FermiLevels 96
2.3.4 ContinuityEquations 97
2.3.5 DiffusionandRecombination 99
2.3.6 GradientsintheQuasi-FermiLevels 101
2.4 p-nJunctions 103
2.4.1 JunctionFormationandBuilt-InPotential 103
2.4.2 SpaceChargeRegion:Depletion
Approximation 107
2.4.3 JunctionRule 110
December2,2011 10:53 PSPBook-9inx6in 00-Hwang–prelims
Contents vii
2.4.4 MinorityCarrierDistributioninNeutral
Regions 114
2.4.5 CurrentinIdealp-nJunctions 115
2.4.6 LeakageCurrentandBreakdownin
p-nJunctions 118
2.4.7 JunctionTunnelDiodes 123
2.5 Metal–SemiconductorContactsandHeterojunctions 125
2.5.1 Metal–SemiconductorContacts 125
2.5.2 Heterojunctions 131
3 MOSStructureandCMOSDevices 139
3.1 MOSStructure 139
3.1.1 BasicConceptsofMOSStructure 139
3.1.2 MOSEquations 150
3.1.3 AnalysisoftheSpaceChargeRegion 152
3.1.4 StrongInversion 157
3.1.5 ThresholdVoltage 159
3.1.6 Capacitancevs.Voltage(C–V)Characteristics 161
3.1.7 QuantumEffectontheMOS(C–V)
Characteristics 167
3.2 MOSFETandItsOperation 171
3.2.1 ConceptofMOSFET 171
3.2.2 UnderstandingMOSFETOperation 177
3.2.3 Current–VoltageCharacteristics 184
3.2.4 SecondaryEffectsinMOSFETs 190
3.3 CMOSCircuits 192
3.3.1 CircuitSymbolofMOSFETs 192
3.3.2 ComplementaryMOSFET(CMOS)Circuits 193
3.3.3 CMOSLogicGates 194
3.3.4 MemoryCircuits 194
4 QuantumWellDevices 205
4.1 IssuesinCMOSDeviceScaling 205
4.1.1 MOSFETScalingTrend 205
4.1.2 Short-ChannelEffects 209
4.1.3 Punch-Through 215
4.1.4 VelocitySaturation 215
4.1.5 MOSFETScalingTheory 219
December2,2011 10:53 PSPBook-9inx6in 00-Hwang–prelims
viii Contents
4.1.6 DopantNumberFluctuation 222
4.1.7 p-nJunctionandOxideTunneling 225
4.2 ApproachestoOvercomingScalingIssuesin
NanoscaleMOSFETs 228
4.2.1 DeviceStructureEngineering 228
4.2.2 GateInsulatorandStackEngineering 230
4.2.3 ChannelandSource/DrainEngineering 232
4.3 Double-GateMOSFETs 234
4.3.1 ClassificationofDouble-GateStructures 234
4.3.2 SimpleModelofDouble-GateMOSFETs 235
4.3.3 QuantumMechanicalCorrectiontothe
ThresholdVoltageofDouble-GateMOSFETs 237
4.4 TunnelingandResonantTunnelingDevices 240
4.4.1 TunnelingFieldEffectTransistor 240
4.4.2 ResonantTunnelingDiodes 242
5 QuantumWireDevices 251
5.1 TransportinOne-DimensionalElectronSystems 251
5.1.1 Backgrounds 251
5.1.2 Ideal1DES 253
5.1.3 Semiconductor1DESs 255
5.1.4 Silicon1DESs 265
5.1.5 WaveNatureofElectrons 266
5.1.6 BallisticTransportinShort-ChannelMOSFETs
UnderHighElectricFields 271
5.2 NanowireMOSFETs 274
5.2.1 EvolutionofMOSFETs 274
5.2.2 AnalyticalModelofNanowireMOSFETs 276
6 QuantumDotDevices 287
6.1 Zero-DimensionalElectronSystems 287
6.1.1 SemiconductorQuantumDotas0DESs 287
6.1.2 CoulombBlockade 292
6.1.3 Single-ElectronTransistors 295
6.1.4 Fock–DarwinStates 297
6.1.5 SpinStatesandQuantumComputing 300
6.1.6 ExampleofSemiconductorSingle-Electron
Transistors 301
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Contents ix
6.2 ModelingofSingle-ElectronTransistors 303
6.2.1 EffectoftheDrainBias 303
6.2.2 EffectofFiniteTemperature 308
6.2.3 EffectoftheGateBias 308
6.2.4 BriefReviewofSingle-ElectronCircuit
Simulation 313
6.2.5 ExamplesofSingle-ElectronCircuits 317
7 MOSFETasaMolecularSensor 335
7.1 Introduction 335
7.1.1 Potentiometryvs.Amperometry 335
7.1.2 FET-Based(Bio)ChemicalSensor 337
7.1.3 TwoTypesof(Bio)ChemicalFETSensor:ISFET
andAffinity-BasedFET 339
7.2 SomeBasicsofChemistryandtheImportanceofH+ 340
7.2.1 SomeBasicsofChemistry 340
7.2.1.1 Aqueoussolution 340
7.2.1.2 pH 341
7.2.1.3 Buffersolution 342
7.2.1.4 ManybiologicalreactionsinvolveH+ 344
7.2.2 ChargesofImportantBiomolecules 345
7.3 EISFET 347
7.3.1 EISFETStructures 347
7.3.1.1 Referenceelectrode 349
7.3.1.2 Electrolyte 349
7.3.1.3 Insulatorfilm 350
7.3.1.4 EI(Electrolyteinsulator)interface 350
7.3.2 TheoryofEISFET[24] 351
7.3.2.1 Theoryofelectricdoublelayer:
thediffusionlayer 354
7.3.2.2 TheHelmholtzlayer 355
7.3.2.3 RelationshipbetweenQ and[H+]in
ei
theelectrolyte 355
7.3.2.4 Theoryofsemiconductorsurface 357
7.3.2.5 Totalchargesinthesystemand
equivalentcircuit 358
7.3.2.6 ISFETcurrentequationrelatingpH
andcurrent 359
