双面Reflow 改单面Reflow.ppt

Design Build Ship Service GlobalOperations ChinaEngineering GlobalOperations ChinaEngineering World WideGlobalOperationsEngineeringBestPracticeConf CallEng BP Concall 030 SingleReflowSolderingProcessDevelopmentforDellFlemingProjectTonnyTongNov20 2008 Topics TeamMemberProductsOverviewCurrentProcessFlowSingleReflowProcessFlowQualificationRunSummary TeamMembers AdedicatedteamleadbyAMEcomprisingactivemembersfromPE EE QA MBUwereformedtoworkforsinglereflowprocessdevelopment ProductOverview ProductinformationCustomer DellProducts MotherboardBuildmodel OEMPCBsize 266 7mmx269 2mmx1 55mmSurfacefinish OSPPartsnumber 1500Components CPU socket 0402 DIMM PCIEProcessflow SMT SI W SProcessChallengesOSPfinishandPTHholefillHighvolumeandcostcontrol Dellmotherboard Productoverview Differentmodel DellFlemingMT DellFlemingDT DellFlemingSFF PCBsize 267 269 1 6mm PCBsize 243 267 1 6mm PCBsize 203 265 1 6mm AllDellmotherboardtotalhaveapprox30 40pcschipcomponentsonbottomside Bottomsideofmotherboard Therearetotal30 40pcschipcomponentsonbottomside thebiggestcompis0805capacitor 0603capacitor 0805capacitor ComponentsatBottomSide CurrentDoubleReflowProcessFlow DEKPrinter HS 50 1 JTReflowOven DEKPrinter Topside HS 60 2 HF3 AOI JTReflowoven Wavesolder HS 60 1 Bottomside SingleReflowProcessflow BenefitSinglereflowprocesshelpsonsolderjointreliabilityduetolessthermalimpactandIMCgrowthcomparingdoublereflowprocessBenefitholefillduetolessOSPperformancedegradingMinimizedprocesscontrolstationMinimizedmanualhandlingCostsavingto60KUSDperlineperyear SingleReflowProcessflow Costsavingcalculation SpecialstationSpecialhandlingchallengeAddaflipmachineAddsupportblockforP P pending CostsavingCancelbottomsidereflow 300KRMB 60Month 5000RMB dayCancelpalletofbottomside 30pcs 1000rmb 30kRMBSavingmanpower 2person perline 1500 2 3000RMB MonthSavingelectricalpower 15kw 24h 30 0 72rmb 7800RMB Month Savingnitrogen 18000RMB Month Costsaving Reflowdepreciationexpenses5000 Month manpower3000 Month electricalpower7800 Month nitrogensaving18000 Month 33800RMB MonthTotalsave33800RMB lineifthenewprocessconductsuccessfully Costsaving FeasibilityAssessment SolderPasteTackyForce TamuraTLF204parameter JIS Z 3284 1994 teststandard JIS Z 3284test Solderpastetackyforce permmTackyforcefromthesolderpastespecis1 5N approx150g Thetestarea 3 14 5 1 2 19 94mm Permmpastetackyforce 150 19 94 7 52g mm 2 2 2 2 2 FeasibilityAssessment SolderPasteTackyForce Dimensions mm inches FeasibilityAssessment ComponentsSize FeasibilityAssessment CompTackyForceCalculation Throughthecalculation itobviouslyshowsthattackyforcefromsolderpasteishighlysafetopreventSMDcomponentsfallingfromtransportationandflipduringassembly componentstackyforcecalculation Primaryconclusion 2 2 Bottomsidescreenprinting sameasnormalBottomsidepick place sameasnormalPCBflip addautomaticPCBinvertertoeliminatemanualhandlingTopsideprinting Withsupportingfixture pressuretoPCBduringprintingwasdistributedtofixture Novibrationatthisstation TopsidePick place 2NplacementforceisnegligibleReflowsoldering tackinessfromsolderpastebeforemeltingandsurfacetensionduringmeltingpreventcomponentfromdropping Transportation NottotouchPCBanytimepriortosoldering ImpacttoPCBduringtransportationcanberesolvedbytackinessfromsolderpaste Aboveofall thereisfeasibilitytorunsinglereflowprocessfordoublesideassembly FeasibilityAssessment StationbyStation ComponentPlaced Bottomsidereflowwithtopsideup Nocompmissing PlacedthecomponthePCBbottomsidesuchas1206or0805capacitorand1206transistor StrikingthePCBfromtopsidetosimulatingasharplyhittingorvibration nocompdroppedfromthePCB Reflowbottomsidewithtopsideup nocompmissedandthesolderjointwasacceptableafterreflow FeasibilityAssessment Simulation QualificationRun TargetToevaluatethepossibilityofsinglereflowprocesswithquality productivityexcellenceVenueanddateLineT25andNov04 Trialbuildplan5pcstestrun focusonbottomsidecompmissingand2DX Rayinspection 20pcs focusontheprocesswhichmaycausecompmissing 75pcs monitortheprocessandverifytherepeatability TVinformationProduct ODMPCBsize 304mmx332mmx1 55mmSurfacefinish OSPTotalcomponents 2754BottomsidecomponentsQTY 765Bottomsidecomponents 0402and1206capacitor transistor smallQFNProcessflow SMT W S SI Inordertodemonstratetheprocessrepeatabilityusingsinglesidereflowprocess TVweselectedhereisbiggerandmuchmorecomponentsatbottomsidethanDellM B thereare765pcscomponentsonbottomsideincluding0402and1206capacitor transistor smallQFN QualificationRun Bottomsideprinting FixPCBbypallet Pickupandplace ReleasePCBfrompallet FlipPCBbymanual topsideprinting FixPCBbypallet Pickupandplace Doublesidereflow TopsideAOI Operatorinspection Bottomsideinspection QualificationRun QualificationRun NoanychangeincurrentprocessincludingIDM tooling processparameterexceptcancelbottomsidereflow CurrentprocessyieldatbottomforTVweselectedis98 Totalinput100pcsinthisqualificationbuild N2wasusedhereinreflowandO2ppmlevelislessthan800ppm 4pcsdefectiveboardsoutof100wasfoundandDPMOforbottomsideis17 Only1pcscomponentwasdroppedduringreflow ForDellmotherboard firstpassyieldforbottomsidewillberelatively99 7 withachievedDPMO 17 duetomuchlessdefectopportunity RootcauseanalysisforcomponentmissingComponentweightactsasaccessaryoftombstonetoincreasetheimbalancelevelofwettingforceduringreflowinthesinglesidereflowprocess thereischanceforcomponentdroppingintheprocessofformingatombstoneifthereisavibrationorshakingN2usedherewithO2ppmatverylowlevel800PPmincreasetheopportunityoftombstonesignificantlycomparingtoairreflowproce