浅析SMT回流焊接缺陷分析

EquipmentforElectronicProductsManufacturingEPE172May．2009SMT122(1.；2.，210046)：（SMT），、，，。，，，，。，SMT。，。：；；；：TN305.93：A：1004-4507(2009)05-0011-05SMTReflowSolderingDefectAnalysisHUYixiao1ZHAOXiongming2ZHUGuibing2(1.NanjingNJStarTechnologyCo.,Ltd;2.NanjingCollegeofInformationJobTechnology,Nanjing210046,China)Abstract:SMTreflowprocessisfacingmorechallengesaselectronicsassemblytrendtowardssmall-scale,high-densityandtheapplicationoflead-free.Itisrequiredtohavestrongcapabilityofdiag-nosisandanalysisonweldingdefectsinordertoattainhighqualityandhighyieldproducts,tofindthere-latedcausesofthedefectstoimprovethemanufacturingprocessandfindthebestsolutiontoprocessandcontrolefficientlythedefectsrate.ItisatargetforSMTindustrytoimprovetheproductqualityandre-ducemaximallythereworkrateorminimizethecostofrework.Thispaperwillfocusonsomedefectsofreflowjointingandprovideideasandmethodstoanalyzerelateddefects.Keywords:ColdSolder;Stonehang;Skewing;Surface;Strain：2009-03-201972－、、。：11EquipmentforElectronicProductsManufacturingEPE172May．2009(Forcedconvection)(Condensation-inert)(Vaporphase)。、。、。。(Profiling)(PCB)/。、、。、、。。/。。。(Fullliquidustemperature)(T1)。。。Sn63/Pb37200～225℃。。15～20℃。()。(MVC,mostvulnerablecomponent)(T2)。MVC“”。5℃“”MVC。、(DIP,dualin-linepackage)、(LED,lightemittingdiode)、。MVC。(T2-T1)。、、。()T1。。/。。4℃20s。。1。SMA。、、、、、、、、、。、、31.1。、。1。1，、12EquipmentforElectronicProductsManufacturingEPE172May．20092、3。PCBPCB。PCBPCB。Sn/Pb210～225℃30～60s。。235～245℃60～90s4。PCB。。PCB。。。PCB。2BGA(a)BGA(b)BGA(a)ERSASCOPEFlipChip(b)ERSASCOPEFlipChip;3FlipChip26024022020018016014012010080604020℃(235-245℃)0.5-2℃/s50-60s50-70s40-70s050100150200250300/s4SnAgCu13EquipmentforElectronicProductsManufacturingEPE172May．2009。PCB。。1.25。。。。。。。。。020101005。。。1005。。。。PCB。。。。PCBSn-PbCuAuSn-Pb。514EquipmentforElectronicProductsManufacturingEPE172May．2009。1.30805IC6。1)2)3)4)5)6)7)PCB8)。89%～92.5%89%92.5%。。40%。。。PCB。、。。。。。。。7。BGA60%。60%。67，(29)15EquipmentforElectronicProductsManufacturingEPE172May．2009PCB8。。90.5%,。2SMT。：[1]Smith.H.W.TechnicalInformationonMICRO-FLOXGForcedConvectionReflowSystem[J].ResearchInc(Apr.,1993):43-48.[2]HenleyPeter.RheometricPumpPrintHeadTechnolo-gy[J].ResearchInc(October1997):22-28.[3]X.Bao,N.C.Lee.EngineeringSolderPastePerformanceViaControlledStressRheologyAnalysisinSurfaceMountInternational[J].SurfaceMounttechnology,September1996:15-19.[4]N.C.Lee,G.P..Evans.SolderPasteMeetingtheSMTChallenge[J].SITEMagazine,June,1987:34-39.[5]IPC-9201,SurfaceInsulationResistanceHandbook[S],1996.8designersandtechnologistsareturningtotheverticaldimensionofthesubstratetomaximizeperformancewhileminimizingchipsizeandpowerconsumption.Thistechniqueof3Dinterconnectleadstolargerto-pographicalstepsonthesubstratewhicharebeyondtheprintingcapabilitiesofconventionallithographicsystemsforcoatingandexposingsuchhighsteps.Newmethodshavebeenproposedtomeetthischal-lengewhichincludespraycoatingofthephotoresistlayer,advancedimagingtechniquestoviewandalignthealignmentfiducials,andprintingopticswithgreaterdepthoffocus.Apparatusesforthesetech-niqueshavebeenproposedandappliedtotypicalstructuresencounteredwithinthefieldoflithographyoverhightopography,withtheresultsshowingtheef-fectivenessofthesenewmethodsforthis3Dtechnol-ogy.REFERENCES:[1]G.Moore.CrammingmorecomponentsontointegratedcircuitsJ.Electronics,Volume38,number8,April19,1965.[2]M.S.Bakir,B.DangandJ.Meindl.Revolutionarynanosiliconancillarytechnologiesforultimateperfor-mancegigascalesystemsM.IEEECustomIntegratedCircuitsConference,2007.[3]P.Ramm.3DIntegrationZ.deliveredinAdvancedPackaging’s3DIntegrationWebcast,June2008.[4]K.Cooper.ConformalPhotoresistCoatingsforHighAs-pectRatioFeaturesZ.Proc.IWLPC,Sept.,2007.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!(15)29