【SMT资料】BGA双球（枕头效应）原因分析及改善对策BGA soldering-Head in pill

BGASoldering-HeadInPillow编辑ppt

In-situobservationofBGAsolderingClassificationofBGAsolderingfailuremodeCasestudyforBGAsolderingOutline编辑ppt1-1ObservationofBGAsolderinggapchangeIn-situobservationofBGAsolderingPeakTemp.Coolingdown编辑pptPKGPCBSoldersphereSolderpasteFluxcleantinoxideSolderball&pastemeltatmeltingpointThickeroxideandweakerfluxactivitycausednon-meltingDuringpeak&coolingNon-meltingcausedheadinpillowReflowProfileofProcess编辑pptClassificationofBGAsolderingfailuremode编辑ppta.

Voidb.Bridged.Cracke.Head-in-Pillowf.Non-wettingc.Missingball编辑pptg.de-wettingh.shifti.solderball编辑pptHead-in-pillowheatingheatingcoolingPeakTemp编辑pptBGAassemblyproblemanalysisBGAproblemComponent(84.8%)PCB(6.1%)Solderpaste(3.0%)SMTprocess(6.1%)BGAballpollution(45%)Padpollution(18.2%)others(9.1%)warpage(12.1%)Profile(3.0%)Pick&place(3.0%)Weakactivity(3.0%)warpage(3.0%)PADpollution(3.0%)编辑pptVoidReflowPCBsubstrateBGAballPasteFluxPowdersizealloycompositionActivatorViscosityOxidationcontaminationCleannessshelflifeSurfacefinishDesignofpadOxidationofpadDegausstimingBridgeProcessSubstrateSolderFluxBendingMissmountingSlump编辑pptDewettingPCBsubstrateBGAballPasteFluxAlloycompositionOxidationcontaminationCleanness&shelflifeSurfacefinishOxidationofpadActivatorCrackPCBsubstrateSolderReflowconditionAlloycompositionDesignBending编辑pptPillowAssemblyDeviceSolderBallSubstrateSurfaceissueShapeIssueCompositiondesignSplitSurfaceoxidationResidueoffluxContamination

Co-planarityBallsizedesignBendingSubstrate(PCB)PasteReflowMountingBendingAlloycompositiondesignPrintingTackinessdecayHeightorvolumeinsufficientFluxactivatorefficiencyHeatinsufficientOver-preheatFluxactivatordecayOxidationofBGAballHalf-meltingornon-meltingPickingPrecisionBGA编辑pptCaseStudyBGAHead-in-pillowdefectissue编辑ppt

Head-in-pillowcross-sectionview编辑pptComponentinspection

Therearesomeblackareasonthesolderball编辑pptSEM-EDSanalysisNormalsurface：C、O<10%TheblackareahasS、Brelements,andhigherC、Ocontentonthesurface编辑pptSEM-EDSanalysisNormalsurfacehashigherOxygencontentTheblackareahasSelements,andhigherC、Ocontentonthesurface编辑pptSEMinspection编辑pptSEMinspection编辑pptSEMinspection编辑pptSMTreflow-Profile

Redsettingprofile

Greenrealprofile编辑pptSMTreflow-Shenmaosolderpaste

pre-heatHeatingto220℃Heatingto230℃Heatingto210℃编辑pptCoolingto235℃Coolingto225℃Heatingto244℃Heatingto

240℃SMTreflow-Shenmaosolderpaste

编辑pptCoolingto100℃Coolingto215℃Shenmaosolderpas