ESD介绍(英文资料

ESD,ESDPresentationOutline,Part1:Introduction/BackgroundPart2:ElectrostaticProblemsPart3:ResistancePart4:IonizationPart5:ChargeMeasurement,ChargingMechanisms,TriboelectricChargingInductionCharging,Triboelectrification,+,-,-,-,+,-,-,-,MATERIALCONTACT,Triboelectrification,+,-,-,-,+,-,-,MATERIALSEPARATION,-,TriboelectricCharging,TheamountofchargetransferreddependsonTypesofmaterialsinvolvedAreaofcontactNumberofcontactsRateofseparationSurroundingenvironment,TriboelectricCharging,GlassHumanHairNylonWoolAluminumPaperCottonSteelRubberNickel,CopperBrass,SilverPolyesterPolyurethanePolyethylenePolypropylenePVCSiliconTeflon,_,+,TriboelectricSeries,TypicalChargeLevels,Typicalcharge(voltage)measuredfordifferentactivitiesWalkingonanuntreatedvinylfloor12kVfor10%RH3kVfor55%RHWorkerstandingup6kVfor10%RH400Vfor55%RH,TypicalChargeLevels,Typicalcharge(voltage)measuredoncommonobjectsWafers5kVWaferCarriers35kVQuartzWare15kVPlasticFilm40kVSmocks10kV,InductionCharging,-,+,+,-,+,+,ChargebyInduction,_,_,_,_,_,+_,+,+,+,Problems,ElectrostaticAttractionContamination“StaticCling”ESDDeviceDamageEquipmentLatchUp,(ESC),Problems,ElectrostaticAttractionContamination“StaticCling”,Problems,ElectrostaticAttractionContamination“StaticCling”,Problems,ESDDeviceDamageEquipmentLatchUp,Problems,ESDDeviceDamageEquipmentLatchUpOftenmisdiagnosedassoftwarebugs.,InducedEMDisturbance,AnExtraPulse,DischargeModels,Tribochargingorinductioncharging+metalcontact=ESDHumanBodyModel(HBM)MachineModel(MM)ChargedDeviceModel(CDM)areusedtosimulateESDeventsfromvarioussources,1500ohms,HumanBodyModel,100kohms,HVPowerSupply,100pF,MachineModel,ZeroohmsandlowL,100kohms,HVPowerSupply,200pF,ChargedDeviceModel,HVPowerSupply,ChargePlate,ChargedDeviceModel,HVPowerSupply,ChargePlate,Grounding(firstlineofdefense),Groundingpreventscharging.Groundeverything-floors,mats,personnel,chairs,garments,machineparts.,SoftGrounds,Usesoftgroundstocontroldischarges.Usingdissipativematerialslimitsdischargecurrenttoalevelthatdoesnotcausedamage.,ResistanceMap,Insulative,103104105106107108109,101310141015,101010111012,SurfaceResistance(Ohms),101102,Dissipative,Conductive,Shielding,TheNeedforStandards,Manycommonitemsarerendereddissipativetocontroldischarges.,ESDcontrolprogramsrequirequalificationoftheseitems.Thusaneedforstandardizedtestmethods.,FlooringWorkSurfacesChairsGlovesGarmentsPackaging,ESDAssociationStandards,GarmentsWorksurfacesFlooringChairsPlanarMaterials10V100V,103104105106107108109,1013,1010,10111012,SurfaceResistance(ohms),TESTVOLTAGE,INPUT,SHIELD/GROUND,V,I,Point-To-PointMeasurements,FacilityGround,RegulatedTestVoltage,INPUTITESTVOLTAGEVSHIELD/GROUND,RTGMeasurements,FacilityGround,MeasuringSmallObjects,5lbprobesaretoollargetomeasuremanyobjectsofinterest.,ThermoformedTraysClamshellsTapeandReelCarriersPickandPlaceSuctionCups,Ionization,Insulatorscannotbegrounded.MethodsofIonGenerationIonizationbyRadiationElectrical(Corona)Ionization,IonizationbyRadiation,RadioactiveDecayAlphaparticlesElectromagneticRadiationSoftX-RayUltravioletInherentlybalanced,CoronaIonization,+_,HIGHVOLTAGE(+),CoronaIonization,HIGHVOLTAGE(+),+,+,+,+,+,+,CoronaIonization,TypesofElectricalIonizersACDCPulseDC,ACandPulseDCIonization,+,+,+,+,_,_,_,_,HIGHVOLTAGE(AC),ACIonization,StepuplinevoltageLowcostHighairflowrequiredtopreventrecombinationNocontrolofbalance,PulsedDCIonization,FasttransportofionswithoutairflowMinimumrecombinationGoodforroomionization,DCIonization,Airionswillrecombineanddriftintheelectricfield.,+,+,+,+,_,_,_,EfficiencyandBalance,_,_,_,_,+,+,TestingIonizers,SuitabilityforApplicationIncomingTestPeriodicVerification,HowWeTestIonizers,Testefficiencyofiongeneration.Howquicklywilltheionizerdischargeachargedsurface.Testthebalanceofpositiveandnegativeairions.Animbalancewillchargeanunchargedsurface.,HowWeTestIonizers,TheinstrumentusedtotestionizersistheCharged-PlateMonitor.,Discharge(Decay)Tests,Evaluatethequantityofionsproducedbytheionizer.Chargeasurfaceandmeasurethetimetoneutralizethecharge.Performforpositiveandnegativecharges.,Float(Balance)Test,Evaluatethebalanceofpositiveandnegativeionsproducedbytheionizer.,Charged-PlateMonitors(CPMs),ConventionalConstruction,PropertiesofCharged,IsolatedConductors,_,GROUND,Q=CV,Chargesaremobile.Theyarefreetoredistributethemselvesonthesurfaceoftheobject,Charge(Q)isfixed.,Capacitanceandvoltagedependonthelocationofthecharged(conductive)object.,C,PropertiesofChargedInsulators,_,GROUND,QX=CV,Chargesarenotmobile.Theycannotredistributethemselvesonthesurfaceoftheobject.,Chargesonaninsulatorcannotberemovedbyconnectingthesurfaceoftheinsulatortoground.,Chargedinsulatorsaremoretroublesometocharacterize.,Strictlyspeaking,thebehaviorofchargedinsulatorscannotbecharacterizedbyQ=CV.,XC,DirectMeasurementofCharge,GROUND,Dischargeisolatedconductiveobjectsintoacoulombmeter.,Destructivetest.,Canttestinsulatorsthisway.,C,_+,_,Q=CV,DirectMeasurementofCharge,Otherobjects(chargedinsulators)mustbeplacedinaFaradayenclosurethatisconnectedtoacoulombmeter.,+,+,+,+,_,_,DirectMeasurementofCharge,ItischallengingtoplaceobjectintoaFaradayenclosurewithoutaddingorsubtractingcharge.Measuringchargeusingthesedirectmethodsmaybeimpractical.(ObjectsmaybetoolargetoplaceintoaFaradayenclosureornotremovable.),+,+,+,+,_,_,MeasuringVoltagesonIsolatedConductors,0000,GROUND,Familiartestequipment,suchasdigitalvoltmetersandoscilloscopes,cannotbeusedtocharacterizeelectrostaticcharges.,Contactingchargedconductiveobjectsquicklydischargestheobject.,Contactinginsulatorsdischargesthecontactpointanddoesntmeasuretheun-contactedsurface.,_,ContactingElectrometers,Veryhighinputimpedance.GROUNDMinorloadingofthechargedconductor.,Okayformeasuringisolatedconductors.Doesntworkforinsulators,C,_+,_,GROUND,Voltagefollower,Minimalloadingofthechargedconductor,Stillcantmeasureaninsulator,C,+,_,_,ContactingElectrometers,PropertiesofChargedObjects,Weoftenevaluateachargedobjectindirectlybyevaluatingitselectricfield.,Instrumentsthatsenseelectricfieldsinclude,ElectrostaticFieldmetersElectrostaticVoltmetersNon-contactingtestmethod.,+,Fieldmeters,Fieldmeterswereoriginallyusedtomeasurelargeobjects.Measuringinauniformelectricfieldisdesired.Point-to-pointorpoint-to-planemeasurementsyielddifferentmeasurementresults.,Fieldmeters,Electrostaticfieldmetersmeasurethefieldstrengthassociatedwithacharge.Theunitofmeasureisthevolt/meter(orsomeotherconvenientdistance).Indicatesthepresenceandapproximatelevelofcharge.Usuallyhand-heldBestsuitedformakinggeneralauditsCost-effectiveformeasuringvoltagesabove3kV.,Fieldmeters,Fieldmetersdonotresolvelowvoltages.Fieldmetermeasurementsvarysignificantlywithdistancefromthechargedobject.Fieldmetersdonotresolvesmallsurfaceareas.TwocommontypesoffieldmetersareInductionFieldmetersChopper-StabilizedFieldmeters,SimplesttypeoffieldmeterNosystemtoimprovedriftandinstabilityWontoperatereliablyinthepresenceofionizationFieldmetersaregroundedinstrumentsandmodifythedata.,InductionFieldmeters,Chopper-StabilizedFieldmeters,DooperateinthepresenceofionizationFeedbacksystemstoimprovedriftandinstabilityperformanceStillrequireafixedspacing,ElectrostaticVoltmeters,Electrostaticvoltmetersusevoltagefeedbacktonulltheelectricfieldbetweenthesurfaceundertestandthevoltmeterprobe.AlsoknownasvoltagefollowerorelectrometerHighdegreeofaccuracythatisindependentofthedistancefromthecharge.Electrostaticvoltmetersgenerallyprovideabetterapproximationofthechargelevelascomparedtofieldmeters,andarebettersuitedformakingaccurateandrepeatablemeasurements.,ElectrostaticVoltmeters,Thesensorcanbeplacedveryclosetothechargedsurfacewithoutarc-over.Thesensorcanresolvesmallsurfaceareas.Veryfreeofdriftandenvironmentalinstability.Wellsuitedforfixedinstallationinequipment.NotagroundedprobePresenceofhighvoltageonthereferencesurfaceWorksinionizationbecausetheyarechopper-stabilized,AC-FeedbackVoltmeter,AC-feedbackelectrostaticvoltmetersarepartfieldmeterandpartelectrostaticvoltmeter-ahybridinstrumentwithsomecharacteristicsoffieldmetersandsomecharacteristicsofelectrostaticvoltmeters.AC-feedbackelectrostaticvoltmeterssenseelectricfieldandsensecapacitance(distance)changesbetweenthesurfaceundertestandtheprobetoindicatesurfacevoltageevenifthedistancechanges.Spacingindependentaccuracyofelectrostaticvoltmeters.Resolvesmallsurfaceareas.,ACFeedbackElectrostaticVoltmeter,ACFeedbackElectrostaticVoltmeter,Alsoknownasaspacingcompensatedfieldmeter,spotmeterHowitislikeavoltmeterHowitislikeafieldmeterReportssurfacevoltageLowcostSpacingindependentaccuracyAgroundedinstrumentResolvessmallobjectsArcoverifusedtoocloseGoodstabilityanddriftperformance,Comparisons,VoltmetersNotcosteffectiveabove3kVExcellentspatialresolutionIntendedforclosespacing,measuringsmallobjectsNotgroundedSpacingindependentaccuracyLowdrift,AC-FeedbackCosteffectiveabove3kVGoodspatialresolutionGoodatclosespacings,measuringsmallobjectsGroundedSpacingindependentaccuracyLowdrift,FieldmetersCosteffectiveabove3kVLowspatialresolutionIntendedforwidespacing,measurelargeobjectsGrounded,UsingVoltmetersandFieldmeters,d,4d-5d,Aselectrostaticvoltmeterscanbeoperatedclosetoachargedsurfacewithoutfearofarc-over,theycanresolvesmallersurfaceareas.,Extraneousfieldscannegatethewholenotionofspatialresolution.,UsingVoltmetersandFieldmeters,_,+,Insulatorsdonothaveuniformchargedistribution.Aschargedensityisnon-uniform,surfacepotentialsarenon-uniform.Whatismeasuredisnebulous.Providesafigureofmerit.,Auditing,Hand-heldmetersareparticularlyusefulforauditing.Groundingisimportant,especiallyforbattery-operatedinstruments.Chargeupobjectsofinterestandseeiftheyretaincharge.,DiagnosticsandContinousMonitoring,Hand-heldinstrumentsarecumbersomeformonitoringinsideofprocessequipment,butmanydohaveelectricaloutputs.Bothfieldmetersandelectrostaticvoltmeterscanhaveremoteprobes.Probescanbefixturedtomonitorasurfac