SMT-17_Doping_CD

,SemiconductorManufacturingTechnologyMichaelQuirk&JulianSerdaOctober2001byPrenticeHallChapter17DopingProcesses,Objectives,Afterstudyingthematerialinthischapter,youwillbeableto:1.Explainthepurposeandapplicationsfordopinginwaferfabrication.2.Discusstheprinciplesandprocessofdopantdiffusion.3.Provideanoverviewofionimplantation,includingitsadvantagesanddisadvantages.4.Discusstheimportanceofdoseandrangeinionimplant.5.Listanddescribethefivemajorsubsystemsforanionimplanter.6.Explainannealingandchannelinginionimplantation.7.Describedifferentapplicationsofionimplantation.,CommonDopantsUsedinSemiconductorManufacturing,Table17.1,CMOSStructurewithDopedRegions,Figure17.1,CommonDopantProcessesinCMOSFabrication,Table17.2,IonImplantinProcessFlow,UsedwithpermissionfromLanceKinney,AMD,Figure17.2,DopedRegioninaSiliconWafer,Figure17.3,Diffusion,DiffusionPrinciplesThreeStepsPredepositionDrive-inActivationDopantMovementSolidSolubilityLateralDiffusionDiffusionProcessWaferCleaningDopantSources,DopantDiffusioninSilicon,Figure17.4,SolidSolubilityLimitsinSiliconat1100C,Table17.3,DiffusionProcess,EightStepsforSuccessfulDiffusion:1.Runqualificationtesttoensurethetoolmeetsproductionqualitycriteria.2.Verifywaferpropertieswithalotcontrolsystem.3.Downloadtheprocessrecipewiththedesireddiffusionparameters.4.Setupthefurnace,includingatemperatureprofile.5.CleanthewafersanddipinHFtoremovenativeoxide.6.Performpredeposition:loadwafersintothedepositionfurnaceanddiffusethedopant.7.Performdrive-in:increasefurnacetemperaturetodrive-inandactivatethedopantbonds,thenunloadthewafers.8.Measure,evaluateandrecordjunctiondepthandsheetresistivity.,TypicalDopantSourcesforDiffusion,SEMATECH“DiffusionProcesses,”FurnaceProcessesandRelatedTopics,(Austin,TX:SEMATECH,1994),P.7.,Table17.4,IonImplantation,OverviewControllingDopantConcentrationAdvantagesofIonImplantDisadvantagesofIonImplantIonImplantParametersDoseRange,ControllingDopantConcentrationandDepth,Figure17.5,GeneralSchematicofanIonImplanter,Figure17.6,IonImplanter,PhotographcourtesyofVarianSemiconductor,VIISion80Source/Terminalside,Photo17.1,AdvantagesofIonImplantation(fromTable17.5),1.PreciseControlofDopantConcentration2.GoodDopantUniformity3.GoodControlofDopantPenetrationDepth4.ProducesaPureBeamofIons5.LowTemperatureProcessing6.AbilitytoImplantDopantsThroughFilms7.NoSolidSolubilityLimit,Table17.5,ClassesofImplanters,Table17.6,RangeandProjectedRangeofDopantIon,Figure17.7,ProjectedRangeChart,Figure17.8,RedrawnfromB.El-Kareh,FundamentalsofSemiconductorProcessingTechnologies,(Boston:Kluwer,1995),p.388,EnergyLossofanImplantedDopantAtom,Figure17.9,CrystalDamageDuetoLightandHeavyIons,Figure17.10,IonImplanters,IonSourceExtractionandIonAnalyzerAccelerationColumnScanningSystemProcessChamberAnnealingChannelingParticles,SchematicofIonSourceChamber,UsedwithpermissionfromAppliedMaterialsTechnology,PrecisionImplanter9500,Figure17.11,SchematicofBernasIonSource,UsedwithpermissionfromAppliedMaterialsTechnology,PrecisionImplanter9500,Figure17.12,InteractionofionSourceandExtractionAssemblies,UsedwithpermissionfromAppliedMaterialsTechnology,PrecisionImplanter9500,Figure17.13,AnalyzingMagnet,Figure17.14,IonImplanterAnalyzingMagnet,PhotographcourtesyofVarianSemiconductor,VIISion80analyzerside,Photo17.2,AccelerationColumn,Figure17.15,DoseVersusEnergyMap,UsedwithpermissionfromVarianSemiconductorEquipment,Figure17.16,LinearAcceleratorforHigh-EnergyImplanters,Figure17.17,SpaceChargeNeutralization,Figure17.18,NeutralBeamTrap,UsedwithpermissionfromVarianSemiconductorEquipment,Figure17.19,ElectrostaticIonBeamScanningofWafer,Figure17.20,ImplantShadowing,Figure17.21,MechanicalScanningofImplantedWafers,UsedwithpermissionfromVarianSemiconductorEquipment,VIISion80IonImplanter,Figure17.22,ElectronShowerforWaferChargingControl,AdaptedfromEatonNV10ionimplanter,circa1983,Figure17.23,PlasmaFloodtoControlWaferCharging,Figure17.24,EndStationforIonImplanter,PhotographprovidedcourtesyofInternationalSEMATECH,Photo17.3,WaferHandlerforanImplantProcessChamber,UsedwithpermissionfromVarianSemiconductorEquipment,VIISion200IonImplanter,Figure17.25,FaradayCupBeamCurrentMeasurement,RedraawnfromS.Ghandhi,VLSIFabricatonPrinciples:SiliconandGalliumArsenide,2ded.,(NewYork:Wiley,1994),p.417,Figure17.26,AnnealingofSiliconCrystal,Figure17.27,SiliconLatticeViewedAlongAxis,UsedwithpermissionfromEdgardTorresDesigns,Figure17.28,IonEntranceAngleandChanneling,Figure17.29,ImplantationDamagefromParticulateContamination,Figure17.30,IonImplantTrendsinProcessIntegration,ExamplesofDifferentImplantProcessesDeepburiedlayersRetrogradewellsPunchthroughstoppersThresholdvoltageadjustmentLightlydopeddrain(LDD)Source/drainimplantsPolysilicongateTrenchcapacitorUltra-shallowjunctionsSilicononInsulator(SOI),BuriedImplantedLayer,Figure17.31,RetrogradeWell,Figure17.32,PunchthroughStop,Figure17.33,ImplantforThresholdVoltageAdjustment,Figure17.34,Source-DrainFormations,Figure17.35,DopantImplantonVerticalSidewallsofTr