Basic-Die-Bond-Process教学讲解课件

BasicDieBondProcessTableofContentIntroductionTypicalDieBondingSequenceDispensingDiePickingDieBondingIntroductionBasicDieBondProcess: ToattachthediestothepadsonthesubstratesIntroductionCommonDieBondProcessesEpoxydiebondingEutecticdiebondingSoftsolderdiebondingTypicalDieBondSequenceStep1:DispensingStep2:DiePickingStep3:DieBondingStep1:StackLoaderSubstrateCommonlyusedsubstratesPCBLeadframeBGACeramicWaferDifferenttypeofwaferring/frame/wafercassetteWafercassetteDiscoK&SWaferringDiscoK&STeflonDcompanyKcompanyDifferenttypeofwafertapematerialMylartapeUVtapeWafflepackBlueMylarTapeColorlessUVTapeWaferFactorsdeterminethedegreeofuniformityofwafertapeDiesizeLargediesizehaveabettertackinessSurfacefinishofthewaferbackSmoothsurfaceofwaferbackhavehighertackinessDurationofdieadhesiontowafertapeThelongerthedieareonthetape,themoretheyadhereWaferFactorsdeterminethedegreeofuniformityofwafertapeExposuretoUVlightThelongertheexposuretoUVlight,thelesstheyadhereStorageconditionItshouldbestoredinamoderateconditiontemp:10-25Chumidity:60-70%TapemountingprocessamountoftensionshouldbeeveninbothX&YdirectionWaferDispensingTime-Pressure-VacuumVolumetricStamping(RotatingDisc)Tool:-Epoxywriting-ShowerHeadTool:-StampingPinDispensingDispensingBackgroundInformation-EpoxyFunctionofepoxyAdheresthedieonsubstrateCommonly-usedepoxyTypicalPropertyTime-Pressure-VacuumSystemAprocessoftheapplicationofcompressedairinapresetperiodforthefluiddispensingApplyVacuumforremovingthe compressedairMaintainthepressurePreventdripping&suckbackDispensingMethod–

Time-Pressure-VacuumSyringewithepoxyVacuumPressureDrawBacksDispensingvolumeepoxyviscositySyringeInternalpressureepoxylevelAirvolumeinsidethesyringe changesfordifferentepoxylevelResponsetimefor“vacuum-suction” and“air-compression”isthus changingwithepoxylevel

Ifthevacuumlevelisnotadjustedproperly,“epoxydripping”&“sucking-inofairbubbles”mayoccureasily.DispensingMethod–

Time-Pressure-VacuumTime-Pressure-dispenser(fromMusashi)Musashidispensingsystemcancompensateepoxylevelchangeinsyringebyreal-timemonitoringontheactualpressureresponse Needtopreparea“full”syringeandan‘empty”syringeinordertoteachthedispenserhowtocompensateTheTP-dispenserwillthenadjustthe“dispensingtime”&“vacuumlevel”accordinglytocompensateforanychangeinsyringeepoxylevelUsercanset“epoxylevelalarm”toavoidrunningoutofepoxyduringproductionrunDispensingMethod–

Time-Pressure-VacuumDispensingMethod–

Time-Pressure-VacuumMusashiConnecttosyringeVolumetricDispensing

ProcessPrinciple PositiveDisplacementSystem (PistonPump)ApplycompressedairPullupthepistontofeed epoxyintothechamberSwitchthevalveportPistonispushedto dispenseepoxyDispensingMethod-Volumetric

ValveChamberPistonSyringe2-positive-displacementpumpsdispensingCycleDispensingfinishesatleftchamberandrightchamberisfilledLeftchamberisfilledupandrightchamberfinishesdispensingValveswitchesDispensingMethod-VolumetricValveswitchesSwitchingvalvePumpbodyPartstobewashedDispensingMethod-VolumetricDispensingMethodologyVolumetricDispensingAdvantagesTruepositivedisplacementdispensingNodrippingInconsistencycomesfrompistonpositionerrorandepoxycompressibilityonlyHighaccuracyDrawBacksSlowepoxyfeed-inrateComplicateddesignandlongertime&costlymaintenanceDispensingTool-WritingL/FPadDispenserL/FAnvilBlockEpoxyDispensingTool-WritingAprocesstodispensetheepoxyontotheleadframewithprogrammabletrajectorytodrawadispensingpatternaccordingtothegivendiesizeAdoptedtowiderangeofdiesize:60x60~1000x1000milsDispenserX,Y,ZMotionDispensingTool-WritingAdvantagesFlexiblefordifferencediesizeEasytocontrolepoxycoverageEasytocontroldietiltandBLTToolsDrawbacksSlowwriting,maydecreaseUPHDispensingTool-WritingDispensingTool-WritingDispensingTool-WritingL/FPadDispensingTool–ShowerHeadShowerHeadDispensingAprocessfordispensingtheepoxyontotheleadframewithafixeddispensingpatternofepoxydotsspeciallydesignedforaparticularrangeofdiesizePractical/applicablerangeofdiesizeforshowerheaddispensing:30x30~150x150milsDispenserYandZMotionDispensingTool–ShowerHeadAdvantage:IncreasingUPHforsmalltomedium-sizediebondingprocessDrawback:Difficulttoset-uptogetaconsistentresultsforallpadsNozzleholesblockageDispensedSamplesDispensingTool–ShowerHeadDispensingMethod-StampingAprocessfordispensingtheepoxyontotheleadframewithadispensedepoxydotaccordingtothestampingpinsizeTypicalrangeofdiesizefortheusageofepoxystamping:7x7~20x20milsDispensingTool–StampingPinTiplengthTipradiusStampingpintipDispensingMethod-StampingAdvantagesSmallepoxydotsizeHighspeedstampingAbletoachieveconsistentvolumeDrawbacksNeedprocesscontroltoavoidtailingDifficulttohandlelowviscosityadhesiveEffectofusageofDispensingMethodCommonproblemsDrippingPre-SqueezeDelayPost-SqueezeDelayTailingInconsistencyVoidPhototakenbyX-rayDispensingAdvantagesofdifferentdispensingmethodDisadvantagesofdifferentdispensingmethodHigherdispensespeedConsistentpatternEaseofBLT&dietiltcontrolProgrampatternSmalldotStampingAbleAcceptableAcceptableUnableAbleShowerheadAbleNotgoodNotgoodUnableUnableWritingDiesizedependentGoodGoodAbleUnableEaseoftailingoccurrenceEpoxycontaminationNeedleBlockageVoidStampingEasytooccurYesNoNoShowerheadAcceptable(viscositydependent)NoEasytooccurEasytooccurWritingMoststableNoAcceptableMoststableDiePickingDiePickingMylarColletWaferEjectorCapEjectorPinDiePickingDiePickingEjectingToolsEjectorPinEjectorChuck(Pinholder)EjectorCapPickingToolsColletEjectingToolPinEjectthediefromtheMylarChuckHoldingthepinCapActasplatformforholdingthedieHolesforvacuumEjectorAssemblyEjectorpinEjectingTool–EjectorPinEjectorpinEjectorpin-sharptypeEjectorpintipEnlargedviewofejectorpintip(sharptype)EjectingTool–EjectorPinEjectorpin-roundtypeEnlargedviewofejectorpin(roundtype)EjectingTool–EjectorPinEjectorPinNotationEjectorpinisnotatedbythedimensionofpintipradiusExamplesR1ejectorpinTipradius=0.022mm=1mil

R5ejectorpin(roundpin)tipradius=0.125mm=5milsR3ejectorpintipradius=0.075mm=3milsR8ejectorpintipradius=0.200mm=8milsR10ejectorpinTipradius=0.300mm=10milEjectingTool–EjectorPinEjectorPinSelection(1)–MaterialTungstenCarbidePlasticTopreventdiebreakingToavoidpinmarkEjectorPinSelection(2)forSmallDieDiesize(>40mils)

SharpPinPreventpickfailureEjectingTool–EjectorPinEjectorPinSelection(3)forLargeDie/LongDieUseroundpin(>40mils)MultiplepinsareusedAvoidstressconcentrationPreventdiecrackingEjectingTool–EjectorPinDieMylarPinEjectorPinSelection(4)forThinDieMultiplesharppinsorCrownpinisusedforejectingthindieAvoidstressconcentrationPreventdiecrackingBrushingisalsoanothermethodEjectingTool–EjectorPinEjectorPinSelection(5)EjectingtoolselectiontableBasedondiedimensionEjectingTool–EjectorPinDefinitionofdiedimensionSchematicdiagramofchuckEjectingTool–EjectorPinMulti-PinEjectorpinchuck/pinholderEjectingTool–EjectorChuckEjectorpinchuck/pinholderEjectorchuckholeEjectingTool–EjectorChuckEjectorcapThinDieCapMulti-pinejectorcapPre-peelingcapforthindieEjectingTool–EjectorCapEjectorcapEjectorcapholeEjectingTool–EjectorCapPickingToolBondArmColletBodyColletPV2BondArm(AD898)ColletBodyColletPick-uptools-ColletIncontactwithdiesurface;applyvacuumandpickupdiefromMylarSelectiondependsondiefeaturese.g.size,adhesionmethodPickingTool-ColletColletBodyPickingTool-ColletDifferentconfigurationofcolletRubbercolletroundtype&rectangulartypeRoundtypeRectangulartypePickingTool-ColletDifferentconfigurationofcollet2-sided&4-sidedcolletNon-contactdiesurface(imagesensorapplication)SelfdiealignmentConsistentPick-positionPickingTool-ColletDifferentconfigurationofcollet4-sidedcolletNon-contactdiesurfaceSelfdiealignmentConsistentPick-positionPickingTool-ColletDifferentconfigurationofcolletHi-tempcolletPickingTool-ColletDifferentconfigurationofcolletTungstencarbidecolletPickingTool-ColletDifferentconfigurationofcolletThinDieColletForthindieapplication,normaldiecolletcenterhadabighole,duringsuckingitmaycrackthedieorcausingvoidinbothlaminatedtapebondingColletisflatsurfaceandonlysmallvacuumholestoreducevoidduringpickupandbondingTapebondedwithalotofvoidsTapebondedwithlittlevoidsPickingTool-ColletDifferentconfigurationofcolletRubbercolletcommonly-used,fornormaldiebonding2-sided&4sidedcolletfordiewithaspecialsurfacecoatingeliminatethepossiblecontaminationbythecontactbetweendieandcolletHi-tempcolletforeutecticbondingabletosustainthehightemperatureofleadframeTungstencarbidecolletforsmalldiebonding(sizerange20milsbelow)aimtopreventthesuck-backphenomenonafterbondinglongerlifetimeFlatColletToavoidvoidcomingoutforthindiebonding(fortapeapplication)PickingTool-ColletDieBondingDieBondingColletL/FAnvilBlockEpoxyDieDieBondingBondarmComparisonAnvilBlockDesignBondarmComparisonRotaryBondarmformirrordieapplicationStandardinAD8912forcolletcompensationinsteadofheavytablecompensation–introducevibrationWeight326g(3timesheavierthanPF2)Normallyforbigdieapplication>300milPV2bondarmStandardbondarmwithoutrotaryLighterweight95gforhighspeedwithlessvibrationNormallyforsmalldie<100milinAD898AD898/AD8912PF2bondarmwithvoicecoilLighterforhi-speedapplication(95g)Movingpayload15gBondarmComparisonAD82890degreerotarybondarmBondarmComparisonAD8930AnvilBlockDesignDispensingAnvilBlockBondAnvilBlockSomeequipwithvacuumholesforbetterholdingofthesubstrateAnvilBlockDesignDispensingAnvilBlockBondAnvilBlockSomeequippedwithvacuumholesforbetterholdingofthesubstrateAnvilBlockDesignMajorParametersondesigninganvilblock:CR,CP,CE,LW,PW,PHAgoodanvilblockdimensionaldesignshouldprovide:Enoughholdingforce

fordieplacementcontrolOptimizedvacuumholdingdistribution

fordietiltingcontrol

PadonLeadframeVacuumholeonAnvilBlockAnvilBlockDesignAvailableanvilblockbasicdimensions(i)50-80mmwidthsubstrate(ii)50-80mmwidthsubstratewithanti-scratchfeature(e.g.LPCC9x9)(iii)15-50mmwidthsubstrate(iv)15-50mmwidthsubstratewithanti-scratchfeature(e.g.LPCC9x9)AnvilBlockDesignAnvilBlockDesign(i)For50–80mmwidthsubstrateAnvilBlockDesignFor50–80mmwidthsubstratewithanti-scratchfeatureAnvilBlockDesignFor15-50mmwidthsubstratewithanti-scratchfeatureAnvilBlockDesignFor15-50mmwidthsubstratewithanti-scratchfeatureSummaryLeadframesurfacefinishing forSurfaceTreatmentLeadframewidth,coating forBasicDimensionsPadsize,substratetype forVacuumHoleGroup

Substraterowpitch forDistanceBetween VacuumHoleGroupVacuumholegroupused forVacuumPortSize

Dispensingmethod forMultiColumnOptionOtherConsiderationsHeating,Down-setFeature,Up-setFeatureAnvilBlockDesignAdditionalTopic1:

EutecticDieBondingEutecticProcessFundamentalLiquiduslineSoliduslineEutecticpointatwhichallthreephases(A,Bandmelt)canexistsimultaneouslyFromphasediagram,eutectichereis50%BVarieddependingonmetaltypesinvolvedBinaryphasediagramExample:Au-SiPhaseDiagram FourdifferentphasesA:Au-SimeltB:Aucrystal+Au-SimeltC:Sicrystal+Au-SimeltD:twophaseAu-SialloyAu-SibinaryphasediagramSi-crystallitesWhyEutecticDieBonding?EutecticbondingtakesadvantageoftherelativelylowermeltingtemperatureofeutecticalloysEutecticbondingproducesmetallurgicalqualitybondbetweendieandsubstrate.TypicalEutecticAlloysEutecticTemp(°C)Au97-Si3360Au80-Sn20280Sn230Au10-Sn90220Sn96.5-Ag3.5220Pb63-37Sn180EutecticBondingMechanismsMetallizationondie-backMetallizationonsubstrateSubstrateInterfaceDieAlloyedregionEutecticsolderDieMetallizationondie-backMetallizationonsubstrateSubstrateBenefits&LimitationsBenefitsGoodthermalconductivityElectricallyconductingGoodfatigue/creepresistanceGoodBLTanddietiltcontrol(esp.forsmallerdice)No-cureandno-fluxprocessHighoperatingtemperaturecapabilityLimitationsHigherprocessingtemperaturesDieback/LFmetallisationisusuallyrequiredIfbaredieareused,ascrubbingactionisrequiredtobreakdownsurfacesilicafilmReworkisdifficultEutecticProcessApplicationsDiscreteSliverplatedcoppersubstrateGoldplatedceramicsubstrateLEDDisplayVCSEL,LaserDiode4mm0.15mmQFNPackageFluxEutecticProcessConcepts:MeltingeutecticmaterialsunderzerobondforcetocontrolbuildupProcess:DieattachatroomtemperatureandreflowovereutecticpointLEDFluxStampingDieAttachBeforeReflowAfterReflowLEDLEDAD8930/UDieBonderSR902ReflowOvenUltrasonicbathofIPAforcleaningfluxresiduesSolderPasteDispensingandReflowConcepts:IncreasethethicknessofeutecticmaterialstoovercomeroughnesssurfaceProcess:DispensingAuSnsolderpasteatroomtemperaturethenreflowovereutecticpoint.DispensingAuSnPastebyDispenserDieAttachatroomtemperaturebyAD8930ReflowunderrecommendreflowprofilebySR902ReflowOvenColletLEDDispenserNozzleAdditionalTopic2:

SoftSolderDieBondingBackgroundSoftSolderdieattachissimilartoepoxydieattach,exceptusingsolderasthedieadhesivematerial

Definitionof“softsolder”:Solderwithliquidustemperature<430oCPhysicalPropertiesofSoftSolder:GoodthermalandelectricalconductivityAbout10timeshigherthansilverepoxyExcellentthermaldissipationduetosmallerjunctiontocasethermalresistance,qjcLowon-stateresistance,RRSHighmeltingtemperatureHighservicetemperature(>150oC)ComparablethermalexpansioncoefficientandhighstrengthLongfatiguelifeevenifunderthesignificantdeformationandcyclicstrainatsolderjointduetodifferentialexpansionandspatialtemperaturegradientDieSolderjointLeadframeApplicationsofSoftSolderDieAttachSoftsolderdieattachisusedinmanydiscretesemiconductorpackageswherelargecurrent,highpowercyclesandhighpowerdissipationareinvolved.SoftsolderprovidesabetterheatdissipationpaththanAg-epoxyaswellasacompliantlayertorelievethethermalstressPowerpackageperformanceMetalbody…………….. 10-350WPlasticbody……………. 10-350WSurfacemount………… 5-25WRFpower……………….. 10-250WServicetemperaturecanbeupabove150oC,atwhichtheAg-epoxydieattachwillnotsurviveTypicalPowerSemiconductorPackagesMOSFET/VoltageRegulatorTO-126TO-220TO-252TO-263SoftSolderDieAttachProcessMagnifiedViewLFIndexDirectionAnviltracks(workingplatform)1.Solderwiremovesdownward&thenupwardtodispensesolderontotheLFpad2.SpankermovesdownwardsandpressontothemoltensoldertomakearectangularsolderpatternHeatedLFWireDispensingSpankingHeaterMoltensolderdotSolderWireMoltensolderpatternDieDieBonding3.BondarmtransfersthediefromwaferframeontothesolderpatterncolletMoltensolderdotMoltensolderpatternDiebondedsampleLFInBondedLFoutAdditionalTopic2:

BondQualityIssuesDieBondingQualityIssuesDiePlacementDierotationTilteddieEpoxybuild-up(filletheight)EpoxycoverageBondlineThicknessDieshearOthercommonerrorsLostdieCrackeddieDamageondiesurfaceSkipbondunitMisorientateddieEpoxyspreadEpoxyoutsidebondareaExcessiveEpoxyEpoxytailingEpoxyvoidCommonProblems&PossibleCausesDiePlacementGoodPlacementErrorPlacementinX-YdirectionDieBondingQualitySpecification

BondPlacementDieplacementPositionshiftedfromthetargetbondpositionConditionofreject:(AD898asexample)X&Yisoutoftherange1milatCp1inXorYdirectionInspectionmethod:MeasurementusingProfileprojectorwith200XReferenceXaxisReferenceYaxisTargetbondingposition

ActualdiebondedpositionYXCommonProblems&PossibleCausesDiePlacement-con’tToohighbondlevelErroradjustmentin3-pointalignmentToosmallBHTablePickDelayToosmallBondDelayNon-leveledbondanvilblockCommonProblems&PossibleCausesDieRotationGoodRotationErrorRotationDieBondingQualitySpecification

DieRotationRotateddieAnglerotatedreferencetothetargetbondpositionConditionofreject:(AD898asexample)Angleisoutoftherange0.5°atCp1.33whenviewedfromaboveInspectionMethod:MeasurementusingProfileprojectorwith200X=AngleofrotationviewedfromaboveReferenceXaxisReferenceYaxisCommonProblems&PossibleCausesRotation-con’tErroradjustmentin3-pointalignmentErroradjustmentinbondarm90degreemotionColletvacuumisnotenoughToohighbondlevelCommonProblems&PossibleCausesCoverageGoodCoverageInadequateCoverageExcessiveCoverageDieBondingQualitySpecification

EpoxyCoverageEpoxyspreadConditionofreject:(AD898asexample)Epoxyisspreadoutof10milsmeasuredfromthedieperimeter.InspectionMethod:MeasurementusingProfileprojectorwith100XEpoxycoverageEpoxycoverageareaafterdiebondedreferencetothedieareaConditionofreject:(AD898asexample)Epoxycoverageislessthan100%ofdieperimeter.InspectionMethod:VisualinspectionusingMicroscope(30X)DieLEpoxyDieEpoxynotcoveralltheperimeterEpoxySpreadEpoxyCoverageCommonProblems&PossibleCausesCoverage-con’tInadequatecoverageToohighbondlevelTooshortbonddelayNon-leveledbondanvilblockToolowbondanvilblocklevelExcessivecoverageToolowbondlevelToolongbonddelayToohighanvilblocklevelCommonProblems&PossibleCausesBondlineThickness&FilletHeightGoodBLTGoodBLTInadequateBLTExcessiveBLTDieBondingQualitySpecification

EpoxyBuild-upEpoxybuild-upAlsocalledFilletHeightThisistheepoxyquantitybuildupontothedieConditionofreject:(AD898asexample)h>(1/2T+b)InspectionMethod:VisualinspectionusingMicroscope(30X)hTDieDIEbT=Diethicknessh=Epoxybuild-upb=Bondlinethickness

DieBondingQualitySpecification

BondlineThicknessBondlinethickness(b)ThicknessoftheEpoxy--measuredfromtheLFtothebottomofdieConditionofreject:boutoftherange10.5milInspectionMethod:MeasurementusingHisometmicroscope(200X)ExampleofBLTResultDiesize:25milx25milDiethickness:9milLeadframe:SOT23-3LCommonProblems&PossibleCausesBondlineThickness-con’tInadequateBLTToohighbondlevelTooshortbonddelayToolowbondanvilblockExcessiveBLTToolowbondlevelToolongbonddelayToohighanvilblocklevelCommonProblems&PossibleCausesDieTiltNoDieTiltDieTiltDieTiltDieBondingQualitySpecification

DieTiltDieTiltTiltupofthediehorizontalsurfaceConditionofreject:(AD898asexample)D>0.6milInspectionMethod:VisualinspectionusingHisometMicroscope(200X)D=DifferencebetweenhighestandlowestcornerofadieDCommonProblems&PossibleCausesDieTiltNon-leveledbondarmUnevenflatnessofsubstrate&colletsurfaceNon-leveledbondanvilblockErroradjustmentin3-pointalignmentInadequatesuckbond&bonddelayDispensingpositionaccuracyDispensingpatternMeasurementtoolsDieBondingQualitySpecification

DieShearForceDieShearForceTheminimumforcerequirementtoshearadieDependsonthediesizeareaShearStrengthAforcesufficienttoshearthediefromitsmountingorequaltotwicetheminimumspecifiedshearstrengthshallbeappliedtothedieusingappropriateapparatusAD898asexampleDiearea<6250mils2Minimumdieshearstrength(Fm)=0.4gf/mils2xDiearea(A)mils2,whereA=lengthxwidthDiearea≥6250mils2Fm=2500gfAcceptanceCriteriaDevice

isacceptedonlywhenthemeasureddieshearstrengthforce(F)withadhesionofdieattachmediaresiduefallsintothefollowingacceptancecriteria:DieattachmediaresidueAcceptancecriteriaLessthan10%Measureddieshearstrength(F)2xFm

Between10%a