电镜基础

LettuceField(16MDRAM)TheoryofScanningElectronMicroscopeHitachiHigh-TechnologiesCorporationNanoTechnologiesSalesDept.ImageSampleObjectiveLens(IlluminationSource)LumpOMCondenserLensProjectionLensScreenImageImageSampleSampleObjectiveLensElectronSourceCondenserLensDeflectionCoilsSEDetectorCRTTEMSEMFluorescentscreenScanningTheoryofScanningElectronMicroscopeDifferenceamongOM,TEMandSEM↓↓↓PrimaryElectronBeamSecondaryElectronBackscatteredElectronCathodeluminescenceSpecimenCurrentTransmittedElectronElectronBeamInducedCurrentSecondaryElectronDetector~10nm(ExcitationVolumeforSecondaryElectronEmission)TransmittedElectron(Scattered)CharacteristicX-RayTheprimaryelectronbeam-specimeninteractionintheSEMTheoryofScanningElectronMicroscopeTheoryofScanningElectronMicroscope－－－－BackscatteredElectronSecondaryElectronSample(Metal)VaccumSimons,et.al10010,0001EnergyofElectron(eV)QuantityofElectrons(Incidentbeamenergy:10,000eV)EnergyspectrumoftheelectronsemittedfromaspecimenTheoryofScanningElectronMicroscopeSecondaryElectronsBackscatteredElectronsScanning(Y)Scanning(X)lScanningElectronProbeSEMSpecimenScanningElectronBeamofCRTLPixelCRTMagnification:(M)=L/lMagnifyingmechanismintheSEMTheoryofScanningElectronMicroscopeSEDetectorSpecimenCRTCameraAmplifierImageSignalHighVoltageDeflectionCoilsDeflectionAmplifierVacuumPumpFilamentWehneltElectronGunAnodeCondenserLensDeflectionCoilsObjectiveLensSpecimenChamberScanningElectronBeamMag.ControlConfigurationofascanningelectronmicroscopeTheoryofScanningElectronMicroscopePhotomultiplierPrimaryElectronBeamSpecimenPhotonsLightGuideSignalCRT+10kVSecondaryElectronScintillatorPhosphorsAlCoatingLayerTheoryofScanningElectronMicroscopeSecondaryelectrondetectionsystemPhotoMultiplierTubeConfigurationofascanningelectronmicroscopeTheoryofScanningElectronMicroscopeObjectiveMovableApertureModelS-3000NSpecimenStageCRTElectronGunSEDetectorSpecimenChamberComparisonamongOM,TEMandSEMTheoryofScanningElectronMicroscopeTheilluminationangle(α)ofascanningelectronmicroscopeFocalLengthObjectiveLensObjectiveMovableApertureSpecimenWorkingDistanceElectronSourceElectronBeamTheoryofScanningElectronMicroscopeαTheoryofScanningElectronMicroscopeComparisonofobjectivemovableapertureholesizeFocusDepth→DeepFocusDepth→ShallowApertureSize:SmallApertureSize:LargeSpecimen:SionPhotoResistPatternAstigmatismcorrectionmethodBeamDiameterBeforecorrectionObjectiveLensElectronSourceElectronBeamXYElectronBeamElectronSourceObjectiveLensStigmatorAftercorrectionYXStigmatorBeamDiameterTheoryofScanningElectronMicroscopeTheoryofScanningElectronMicroscopeAftercorrectionBeforecorrectionUnderfocusJustfocusOverfocusJustfocusAstigmatismcorrectionmethodSpecimen:Tracheaofrat一一一一一一一一一一一一一一ZExcitationDepthforSecondaryElectronEmission一一一一SecondaryElectronsSecondaryElectronsCarryingSurfaceInformationOfSpecimenSESESecondaryElectronsCarryingInnerInformationOfSpecimenPrimaryElectronBeamBSEBackscatteredElectronsSpecimenSEandBSEemittedfromsolidsampleTheoryofScanningElectronMicroscope1kV2kV3kV1020304050(nm)Beam　Invading　depthTheoryofScanningElectronMicroscopeComparisonofhighandlowaccleratingvoltageTheoryofScanningElectronMicroscopeHighAccleratingVoltageLowAccleratingVoltageVacc:15kVVacc:1.0kVSpecimen:SolarBatteryTheoryofScanningElectronMicroscopeChage-upPhenomenaEliminateChage-upPhenomenaVacc:1.5kVVacc:0.7kVSpecimen:SiO2onPhotoResistLinePatternObservationatloweracceleratingvoltagesPrimaryElectronBeamReducingcharge-upwithNatural-SEM－＋＋－－－－－ＭＭeeObjectiveLensBSEDetectorResidualGasＭHighPressure(1.0Pa～270Pa）NonConductiveSpecimenTheoryofScanningElectronMicroscopePG1PG2FilamentCondenserLensapertureOrificeNVVacuumGaugeVacuumcontroller(Real-time)VacuumconditionpresetRP1RP2DPLowVacuumConditionBSEdetectorV8V6V9V3V4V1SpecimenV5V7HighVacuumConditionV2BlockdiagramofevacuatingsystemTheoryofScanningElectronMicroscopeWehneltAnodeElectronBeamV0ElectronBeamV01stAnode2ndAnodeFlashingVoltageV1V0:AcceleratingvoltageV1:ExtractionvoltageBiasVoltageControlThermionicEmissionColdFieldEmission(～6.5kV)FilamentCurrentControlFilamentComparisonofelectrongunsTheoryofScanningElectronMicroscopeTheoryofScanningElectronMicroscopeEnergySpreadEffectofchromaticaberrationΔV=～2eVTungstenFilamentCrossoverofLowEnergyElectronsCrossoverofHighEnergyElectronsΔV=～0.2eVFETipCrossoverofLowEnergyElectronsCrossoverofHighEnergyElectronsComparisonofelectronsourcesTheoryofScanningElectronMicroscopeFETipTungstenFilament750μmElectronSourceTypeofEmissionOperatingVacum(Pa)Brightness(A/cm2･str)SourceSize(μm)EnergySpred(eV)LifeTime(h)TungstenFilamentThermonicFieldEmissionColdFE10-5～10-85x105108300.012.00.2502000Primary　beamLensSE　DetectorSpecimen３)In-lens　typePrimary　beamSE　DetectorLensSpecimen１)Conventional　type(Out-Lens)SE　Detector(Upper)SpecimenLensPrimary　beam２)Snokel　typeSE　Detector(Lower)TheoryofScanningElectronMicroscopeHi-SEMS-4300S-4700S-5200OutLensType(W-SEM,S-4300)PrimaryBeamLensSpecimenSEDetectorTheoryofScanningElectronMicroscopeSnorkelType(S-4700&S-4800)SEDetector(Upper)SpecimenLensPrimarybeamSEdetector(Lower)TheoryofScanningElectronMicroscopeIn-LensType(S-5200)PrimaryBeamLensSEDetectorSpecimenTheoryofScanningElectronMicroscopeTheoryofScanningElectronMicroscopeWfilamentSEMOutlensFE-SEMSnorkellensFE-SEMIn-LensFE-SEM0.51.010300.51.01020Acc.(kV)Resolution(nm)ComparisonofresolutionSelectUpperand　LowerDetectorsLensPrimarybeamTheoryofScanningElectronMicroscopeUpperHighResolutionLowerTopographicImageNonConductiveSamplesTheoryofScanningElectronMicroscopeNon-ConductiveSamplesObservationSpecimen:CeramicsVacc:1kVUpperDetectorVacc:1kVLowerDetector