WLCSP-bumping

WLCSPANDFLIPCHIPPRODUCTIONUSINGELECTROLESSNi/AuPLATINGANDWAFERLEVELSOLDERSPHERETRANSFERTECHNOLOGIESCertifiedISO9001:2000&ISOTS16949ConfidentialTECHNOLOGIESDr.ElkeZakelPacTechGmbH–PackagingTechnologies,Inc.Nauen,Germany146141.e-Nickel/GoldUBM2.SolderSphereTransfer3.ProcessEvaluation4.FlipChipSizedBumps5.CostModelPresentationOutlineELECTROLESSWAFERLEVELSOLDERWLCSPBumpSolderUBMCertifiedISO9001:2000&ISOTS16949Confidentialultra-SB²PacLine3000ELECTROLESSNi/AuPLATINGWAFERLEVELSOLDERSPHERETRANSFER1)Yield2)Throughput3)CostUnderBumpMetallization(UBM)IntegratedCircuit(I/Opad)UBMFunctions:1)Solderablesurface2)Electro-migrationbarrier3)Thermal-migrationbarrier4)Increasestandoff5)Currentdistribution6)ProtectfinalmetalUBM-UnderBumpMetallurgy(MostofWorld)BLM-BumpLimitingMetallurgy(IBM)UBL-UnderBumpLayer(Japan)CertifiedISO9001:2000&ISOTS16949ConfidentialBumpUBMUBMRequirements:1)Adhesiontopadmetal2)Lowstress3)Lowelectricalcontactresistance4)CompatibilitywithprobedI/Opads5)Compatiblewithbump(SnPb,SnAgCu,SnAu,Epoxy,…)CommonUnderBumpMetallizations1)Sputtered:Al/NiV/CuDelcoElectronics“Flex-on-Cap”Ti/NiV/Au,etc…Smallervolumes-research2)Evaporated:Cr/CrCu/CuIBMtechnologyfrom“C4”era3)Electroplated:CuPillarHighstandoffAuBumpSignificantvolumesinJapan4)Printed:SilverAlloysNextgenerationNanotechnologyR&D5)Electroless:Nickel/GoldLowestcostCertifiedISO9001:2000&ISOTS16949Confidential5)Electroless:Nickel/GoldLowestcostNickel/PalladiumElectrolessNi/AuBumpWetChemicalProcessBatchProcessNoPhotolithographyorHighVacuumProcessingUsedforWLCSP,FlipChip,ACA1Sputtered(Ti/NiV/Cu)2Evaporative(Cr/CrCu/Cu)3Electroplated(CuorAu)4Printed(Ag)5Electroless(Ni/Au)1)CleanPadMetal1)CleanPadMetal1)CleanPadMetal1)PrintMetal1)Platee-Ni/Au2)SputterTi/NiV/Cu2)ApplyPhotoresist2)SputterTi/CuSeed3)ApplyPhotoresist3)Soft-bakePhotoresist3)ApplyPhotoresist4)Soft-bakePhotoresist4)Photo-exposeResist4)Soft-bakePhotoresist5)Photo-exposeResist5)ImageReversalBake5)Photo-exposeResist6)DevelopResist6)FloodExpose6)DevelopResist7)PostBake7)DevelopResist7)PostBakeUBM:ProcessFlowComparisonsCertifiedISO9001:2000&ISOTS16949Confidential7)PostBake7)DevelopResist7)PostBake8)PlasmaDescum8)PlasmaDescum8)PlasmaDescum9)WetEtchCu9)EvaporateCr/CrCu/Cu9)PlateCuorAu10)DumpRinse10)SolventLiftOff10)DumpRinse11)WetEtchNiV11)SolventClean11)StripPhotoresist12)DumpRinse12)DumpRinse/SRD12)DumpRinse13)WetEtchTi13)WetEtchTi/CuSeed14)StripPhotoresist14)DumpRinse/SRD15)DumpRinse/SRD4)ZnStripIncoming1)PassClean2)AlEtch5)ZincateIISilicon,OrganicsZn3)ZincateZn-AlReplacementElectrolessNi/AuProcessFlow(AluminumBasedICs)Al2O3CertifiedISO9001:2000&ISOTS16949ConfidentialNiPNiNi/PAutocatalyticReactionAu/Nireplacementreaction6)NiPlateCont.7)GoldPlateNi–ZnReplacement6)NiPlateAu6)NiPlateCont.ElectrolessNi/AuPlatingVideoCertifiedISO9001:2000&ISOTS16949ConfidentialBumpFunctions:1)ElectricalInterconnect2)ThermalInterconnect3)PassiveAlignmentIntegratedCircuit(PadI/O)WaferBumpingCertifiedISO9001:2000&ISOTS16949ConfidentialBumpRequirements:1)AdhesiontoUBM2)Lowelectricalresistance3)Highthermalconductivity4)StableintermetallicwithUBMBumpUBMTermsusedtodescribewaferbumping:FlipChipC4Flex-on-CapSolderInterconnectFCOB(FlipChipOnBoard)C4NPBumpingFlipChipSolderis200mmtallUnderfilledduringassemblyWaferBumping-FlipChip&WLCSPCertifiedISO9001:2000&ISOTS16949ConfidentialBumpingWaferBumpingSolderBumpingDCA(DirectChipAttach)MicroBGAUltraCSPCSPWLCSPWLCSPSolderis200mmtallNounderfillStencilPrintBallDropLaserJetSphereTransferVacuumSqueegeeSphereReservoirCapillaryReflowLaserAlignStencilPrintPasteAlignStencilDropBallsDropBalls&ReflowAligntoWaferPickupSpheresCertifiedISO9001:2000&ISOTS16949ConfidentialRaiseStencilReflowRaiseStencilReflowRaiseHeadReflowLowerSpheresStencilPrintSolderPasteBallDropSolderJetWaferLevelSolderSphereTransfer(CSP)1)PastePrint1)Flux1)SolderJet&Reflow1)Flux2)Reflow2)Drop2)Inspect2)Transfer3)Clean/SRD3)Reflow3)Reflow4)Inspect4)Clean/SRD4)Clean/SRD5)Inspect5)InspectSolderDeposition:ProcessFlowComparisonsWaferLevelSolderSphereTransfer(FlipChip)1)Flux/Drop/Reflow/Inspect/Rework2)Clean/SRDWLCSPFlipChipCertifiedISO9001:2000&ISOTS16949Confidential5)Inspect5)InspectWaferLevelSolderSphereTransfer(GangBallPlacement)SolderSpheresinReservoirVacuumHeadLoweredintoSolderSpheresReservoirSolderSpheresAttachedonVacuumToolingPlateCertifiedISO9001:2000&ISOTS16949ConfidentialRemovingExcessSolderSpheresviaAirKnifeAligntoolingwithWafer(viadoublevisioncamera)LowerHeadontoWaferandBringSpheresintoContactwithI/OPadsRaiseTransferHeadRemoveWaferforReflowandCleanWaferLevelSolderSphereTransferVideo(GangBallPlacement)CertifiedISO9001:2000&ISOTS16949ConfidentialProcessEvaluation–WaferLevelSolderSphereTransfer1)Yield2)ThroughputTestVehiclePropertiesProcessStepEquipmentYieldWafers/Hr1.UBMDepositione-Ni/Au(PacLine3000)2.FluxDepositionSpinCoater(SpinPacSC200)3.SphereTransferBasicWLSSTTool(Ultra-SB2)4.ReflowLinearOven(Sikama)5.WaferCleanSolventClean(MegaPacMP300)6.InspectionMicroscope(OlympusMX50)CertifiedISO9001:2000&ISOTS16949Confidential2)ThroughputWaferSiz