IPC-7095E

2024–August

DesignandAssemblyProcessGuidanceforBallGridArrays(BGAs)

SupersedesIPC-7095D-WAM1

June2019

AninternationalstandarddevelopedbyIPC

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IPC-7095E

DesignandAssemblyProcessGuidanceforBallGridArrays(BGAs)

IfaconflictoccursbetweentheEnglishlanguageandtranslatedversionsofthisdocument,theEnglishversionwilltakeprecedence.

DevelopedbytheBallGridArrayTaskGroup(5-21f)oftheAssemblyandJoiningCommittee(5-20)ofIPC

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Supersedes:

IPC-7095D-WAM1–June2019IPC-7095D-AM1–June2019IPC-7095D–June2018

IPC-7095C–January2013IPC-7095B–March2008IPC-7095A–October2004IPC-7095–August2000

Usersofthispublicationareencouragedtoparticipateinthedevelopmentoffuturerevisions.

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ThisPageIntentionallyLeftBlank

August2024

IPC-7095E

IPC-7095E

August2024

PAGE\*roman

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Acknowledgment

Anydocumentinvolvingacomplextechnologydrawsmaterialfromavastnumberofsourcesacrossmanycontinents.WhiletheprincipalmembersofIPCBallGridArrayTaskGroup(5-21f)oftheComponentMountingSubcommittee(5-21)oftheAssemblyandJoiningCommittees(5-20)areshownbelow,itisnotpossibletoincludeallofthosewhoassistedintheevolutionofthisstandard.Toeachofthem,themembersofIPCextendtheirgratitude.

AssemblyandJoiningCommittee

Cochairs

MileaKammer

HoneywellInternationalUdoWelzel

RobertBoschGmbH

ColdJoiningPress-FitTaskGroup

Chair

RobertRowland

AxiomElectronics,LLC

TechnicalLiaisonoftheIPCBoardofDirectors

BobNeves

Microtek(Changzou)Laboratories

BallGridArrayTaskGroup

ColetteAnctil

CollinsAerospaceTiberiuBaranyi

FlextronicsRomaniaSRL

WilliamBeairRaytheonCompany

KevinBennett

AxiomElectronics,LLCDavidBernard

DavidBernardConsultancy

ErikBjerke

BAESystemsGeraldLeslieBogert

BechtelPlantMachinery,Inc.

LanceBrackRTX

MichaelBrinkley

AxiomElectronics,LLCRobertE.Cochran

PrivateIslandNetworksInc.

RobertCooneyCollinsAerospace

FrancescoDiMaioGESTLABSS.r.l.

MiguelDominguezContinentalAutomotive

MarkDuncan

LockheedMartinCorporationClaireDvorak

NorthropGrumman

DanEzenekweCollinsAerospace

TonyFeldmeier

HoneywellAerospaceMinneapolisXiaopengFeng

AECCAERO-ENGINCONTROL

SYSTEMINSTITUTE

WilliamJ.Fish

L3HarrisTechnologiesCommunicationSystems–West

BrianFlemmingNationalInstruments

BenGumpert

LockheedMartin-Missiles&FireControl

DavidD.Hillman

HillmanElectronicAssemblySolutionsLLC

KunbinHuang

APCBElectronics(KunShan)Co.,Ltd.

ConstantinHudonEastWestQuebec

FrankHuijsmans

PIEKInternationalEducationCentre(I.E.C.)BV

SharissaJohns

LockheedMartinMissiles&FireControl

HaberlyBKahn

LockheedMartinCorporationMileaJ.Kammer

HoneywellInternational

JosephE.KaneBAESystems

RussellKido

PracticalComponentsInc.

NathanKnipe

LockheedMartinMissiles&FireControl

DaleLee

PlexusCorp.GuangXiangLU

ContinentalHolding(China)Co.,

LtdHongyuLuo

CiscoSystems(China)Inc.

LathaM.S

KaynesTechnologyIndiaLimitedKarenE.McConnell

NorthropGrummanCorporation

MikeMorris

NorthropGrummanCorporationHisaoNishimori

ToyotaMotorCorporation

TimothyJohnPearsonCollinsAerospace

KangRen

AVICXi’anAeronauticsComputingTechniqueResearchInstitute

TomRovere

LockheedMartinMissionSystems&Training

RobertRowland

AxiomElectronics,LLCJoseMaServinOlivares

VitescoTechnologies

VernSolberg

SolbergTechnicalConsultingBhanuSood

NASAGoddardSpaceFlight

CenterGeokAngTan

DSONationalLaboratories

DonaldTyler

TenEyckGroup,LLCBillR.Vuono

QorvoUS,Inc.

UdoWelzel

RobertBoschGmbHFujiJunWu

ToyotaMotorCorporation

BaozhuXiaoWDC

SpecialRecognition

KevinBennett

AxiomElectronics,LLCDavidBernard

DavidBernardConsultancy

MichaelBrinkley

AxiomElectronics,LLCFrancescoDiMaio

GESTLABSS.r.l.

TonyFeldmeier

HoneywellAerospaceMinneapolisBenGumpert

LockheedMartin-Missiles&Fire

ControlConstantinHudon

EastWestQuebec

KangRen

AVICXi’anAeronauticsComputingTechniqueResearchInstitute

RobertRowland

AxiomElectronics,LLC

TableofContents

SCOPE 1

Purpose 1

Intent 1

Useof“Lead” 1

AbbreviationsandAcronyms 1

TermsandDefinitions 1

Solder-Mask-Defined(SMD)BGALand 1

Non-Solder-MaskDefined(NSMD)BGALand 1

NonwetOpen(NWO) 1

Head-on-Pillow(HoP) 1

APPLICABLEDOCUMENTS 1

IPC 1

JointStandards 2

JEDEC 3

EIA 3

SELECTIONCRITERIAANDMANAGINGBGAIMPLEMENTATION 3

Overview 3

DescriptionofAssemblyInfrastructure 4

LandPatternsandPrintedBoardConsiderations 4

TechnologyComparison 5

MultidieModule(MDM)andSysteminPackage(SiP) 5

Microprocessors 5

EscapesandRoutingConsiderations 6

WireBonding 6

AssemblyEquipmentImpact 8

StencilRequirements 8

InspectionRequirements 8

Test 8

Methodology 8

ProcessStepAnalysis 9

BGALimitationsandIssues 9

VisualInspection 9

MoistureSensitivity 10

BGAandBoardCoplanarityand

Warpage 10

Rework 11

Cost 11

VoidsinBGAs 11

PadCratering 11

Head-on-Pillow(HoP)Defect 13

NonwetOpen(NWO)Defect 14

ReliabilityConcerns 14

COMPONENTCONSIDERATIONS 15

SemiconductorPackagingComparisons

andDrivers 15

PackageFeatureComparisons 15

BGAPackageInfluencers 16

CostConcerns 16

ComponentHandling 16

ThermalPerformance 18

SpatialConstraint 18

ElectricalPerformance 18

MechanicalPerformance 18

DieMountingintheBGAPackage 19

WireBonding 19

FlipChip 20

ChangingBGATerminationMaterials 20

Deballing 20

Reballing 20

OptionsforNonreballedBGAs 21

Two-StageProcess 21

Mixed-EutecticandNear-EutecticSolderProcessing 21

UnderfillforMixed-AlloySoldering 21

Standardization 22

IndustryStandardsforBGAs 22

BGAPackage 22

Fine-PitchBGA(FBGA)Package 22

Fine-PitchRectangularBGA(FRBGA)Package 22

Die-SizeBGA(DSBGA)Package 22

BGAPackagePitch 23

LandPatternDesign 24

BGAPackageOutline 24

BallSizeRelationships 24

Package-on-Package(PoP)BGA 25

Coplanarity 25

ComponentPackagingStyle

Considerations 26

SolderBallAlloys 26

SnPbAlloys 26

Pb-FreeAlloys 26

Low-TemperatureSolders 27

DriversforLow-TemperatureSolders 27

ChoiceofLow-TemperatureSolder

Alloys 27

SnBiSolderAlloySystem 27

DuctilityEnhancementofSnBiSolders 28

PolymericReinforcementofSnBiSolderJoints 28

BallAttachProcess 29

CeramicBallGridArray(CBGA) 29

CeramicColumnGridArrays(CCGAs) 30

Tape-BasedBallGridArrays(TBGAs) 34

Multiple-DiePackaging 34

System-in-Package(SiP) 35

Three-Dimensional(3D)FoldedPackageTechnology 35

BallStack 35

FoldedandStackedPackaging

Combination 36

Package-on-Package(PoP) 36

BenefitsofMultiple-DiePackaging 36

BGAConnectorsandSockets 37

MaterialConsiderationsforBGA

Connectors 37

AttachmentConsiderationsforBGAConnectors 37

BGASocketMaterialsandTypes 38

AttachmentConsiderationsforBGA

Sockets 38

BGAConstructionMaterials 39

TypesofBGASubstrateMaterials 39

BismaleimideTriazine(BT)Glass 39

EpoxyGlass(FR-4) 39

FireRetardantsforFR-4 39

Ceramic 39

Flexible(Nonreinforced)BaseFilms 40

BGASubstrateMaterialsProperties 40

CoefficientofThermalExpansion

(CTE) 40

GlassTransitionTemperature(Tg) 40

FlexuralModulus 40

DielectricProperties 41

MoistureAbsorption 41

FlatnessRequirements 41

BGAPackageDesignConsiderations 41

PowerandGroundPlanes 41

SignalIntegrity 42

HeatSpreaderIncorporation 42

BGAPackageAcceptanceCriteriaandShippingFormat 42

MissingBalls 42

VoidsinSolderBalls 43

SolderBallAttachIntegrity 43

PackageandBallCoplanarity 43

ExampleforFine-PitchBGA(FBGA)Coplanarity 44

MoistureSensitivity(Baking,Storage,HandlingandRebaking) 44

ShippingMedium(TapeandReel,Trays,Tubes) 45

PRINTEDBOARDSANDOTHERMOUNTINGSTRUCTURES 45

Substrates 45

OrganicSubstrates 45

InorganicSubstrates 45

High-DensityInterconnect(HDI)

Build-UpLayers 45

BaseMaterialsConsiderations 46

ResinSystems 47

LaminateMaterialProperties 47

ThermalExpansion 47

GlassTransitionTemperature(Tg) 47

TimetoDelamination(T260,T280and

T300) 48

MoistureAbsorption 48

Reliability 48

PrintedBoardSurfaceFinishes 48

Hot-AirSolderLeveling(HASL) 49

SnPbHot-AirSolderLeveling(HASL) 49

Pb-FreeHot-AirSolderLeveling

(HASL) 50

OrganicSolderabilityPreservative(OSP)Coatings 50

NoblePlatings/Coatings 50

ElectrolessNi/ImmersionAu(ENIG) 50

ElectrolyticNi/ElectroplatedAu 52

ElectrolessNi/ElectrolessPd/

ImmersionAu(ENEPIG) 52

DirectImmersionAu(DIG) 53

ImmersionAg 53

ImmersionSn 54

SolderMask 54

Wet-andDry-FilmSolderMasks 54

JettableSolderMask 54

RegistrationofBoard-to-PanelImage

forSolderMask 55

ViaProtection 55

EncroachedVias 55

ViaTenting,PluggingandFilling 55

PRINTEDCIRCUITASSEMBLYDESIGNCONSIDERATIONS 58

ComponentPlacementandClearances 58

Pick-and-PlaceAssembly 58

ReworkRequirements 58

GlobalPlacement 59

AlignmentLegends(SilkscreenedInk,

CuFeatures,Pin1Identifier) 59

AttachmentSites(LandPatternsand

Vias) 60

LandDiameterSizeandItsImpacton

Routing 60

Solder-Mask-Defined(SMD)Landand

Metal-DefinedLandDesigns 61

Metal-DefinedLands 62

Solder-Mask-Defined(SMD)Lands 62

ConductorWidth 62

ViaSizeandLocation 62

ParametersAffectingSolderMaskon

BGAs 64

Multiple-GridBGALandPatternArrayDesigns 65

EscapeandConductorRouting

Strategies 65

EscapeStrategies 68

SurfaceConductorandSpaceWidth 68

Land-to-Via(DogBone)Routing

Patterns 69

DesignforMechanicalStrainMitigation 70

UncappedVia-in-LandandItsImpacts

onReliability 71

Fine-PitchBGA(FBGA)

Microvia-in-LandStrategies 72

PowerandGroundConnectivity 73

ImpactofWaveSolderonTop-Side

BGAs 73

Top-SideReflow 73

ImpactofTop-SideReflow 73

MethodsforAvoidingTop-SideReflow 75

Top-SideReflowforPb-FreeBoards 75

TestabilityandTestPointAccess 75

ComponentTesting 75

SolderBallDamageDuringTestand

Burn-In 76

PrintedBoardTesting 77

PrintedBoardAssemblyTesting 78

PrintedBoardAssemblyFlexureDuringTesting 79

In-CircuitTest(ICT)Concerns 79

FunctionalTest(FT)Concerns 79

OtherDesignforManufacturability

(DfM)Issues 79

Panel/PalletDesign 80

In-Process/End-ProductTestCoupons 80

ThermalManagement 82

Conduction 82

Radiation 82

Convection 83

ThermalInterfaceMaterials 83

Adhesives 83

Greases 83

Phase-ChangeMaterials(PCMs) 84

Gels 84

ThermallyConductivePressure-Sensitive

Tape 84

HeatSinkAttachmentMethodsfor

BGAs 84

InteractionbetweenBGApackagingtechnologies 86

BGAASSEMBLY 86

SurfaceMountAssemblyProcesses 86

SolderPasteandItsApplication 86

ParticleSizeandPasteSelection 87

StencilThicknessandApertureDesign 87

Fine-PitchPrintingTechnology 89

CavityPrinting(3DStencil) 90

CavityPrintKeep-OutZone 91

ImportanceofPasteVolume 91

ComponentPlacementImpact 92

VisionSystemsforBGAPlacement 92

Pick-and-PlaceMachineCapabilityforNonstandard-GridBGAComponents 93

OfflineTeaching 93

InlineProduction 93

ReflowSolderingandProfiling 94

Forced-GasConvection 94

ReflowAtmosphere 94

Time/TemperatureProfiles 94

ThermocoupleAttachment 97

ThermalProfilingforBackward-CompatibilitywithSnPbandPb-Free

Alloys 97

Low-TemperatureSolderingofBGAComponents 98

UniqueProfileforEachPrintedBoardAssembly 101

EffectsofMaterialsonFluxActivation,ComponentDamageandSolderability 101

Cleanvs.No-Clean 102

FluxResiduesThatRequireCleaning

(Clean) 102

FluxResiduesThatDoNotRequire

Cleaning(No-Clean) 102

PackageStand-Off 102

ProcessesAfterAssembly 103

ConformalCoatings 103

UseofUnderfillsandAdhesives 104

UnderfillCoverage 106

Corner-AppliedAdhesive 108

SolderJointEncapsulantMaterials

(SJEMs) 109

DepanelingofPrintedBoardsand

Modules 110

InspectionTechniques 110

X-RayInspection 110

X-RayImageAcquisition 112

DefinitionandDiscussionofX-Ray

SystemTerminology 113

2DTransmissionX-RayTechnology 115

ObliqueViewingInspectionUsingTransmissionX-RayTechnology 115

Cross-SectionalX-RayTechnologies 116

TransmissionX-rayorComputed

Tomography 116

AutomatedX-rayInspection(AXI) 117

X-RayImageAnalysis 117

FieldofView 118

ManualX-rayInspection(MXI)ThermalReflowSimulator(HeatedStage) 119

ScanningAcousticMicroscopy(SAM) 119

BGAStand-OffMeasurement 120

OpticalInspection(Endoscopy) 121

CrackedPeripheralInterconnectDeterminations 122

DestructiveAnalysisMethods 122

Cross-Sectioning 122

DyePenetrantMethods 123

TestingandProductVerification 124

ElectricalTesting 124

FunctionalTest(FT)Coverage 124

Burn-InTesting 124

ProductScreeningTests 125

VoidIdentification 125

SourcesofVoids 125

VoidClassification 126

VoidsinBGASolderJoints 127

Macrovoids 127

PlanarMicrovoids 127

ShrinkageVoids 127

MicroviaVoids 127

IntermetallicCompound(IMC)

Microvoids 127

PinholeVoids 127

VoidMeasurement 128

X-RayDetectionandMeasurement

Cautions 128

ImpactsofVoids 128

VoidProtocolDevelopment 128

SamplingPlansforVoidEvaluation 130

ProcessControlforVoidReduction 131

ProcessParameterImpactonVoid

Formation 131

SolderPasteFormulation 131

SolderPasteVolume 131

Component,PrintedBoardandSolder

PasteContaminationandOxidation 131

ReflowProfile 132

ReflowAtmosphere(Nitrogenor

Oxygen) 132

MultipleReflowCycles 132

LandSurfaceFinishandVoiding 132

Vacuum-AssistedReflowSoldering

forVoidReduction 132

ProcessControlCriteriaforVoids

inSolderBalls 134

ProcessControlCriteria 136

SolderDefects 136

SolderBridging 136

ColdSolder 136

Opens 136

Insufficient/UnevenHeating 137

Head-on-Pillow(HoP) 137

DynamicWarpage 138

ReflowProfile 138

SolderPaste 139

HowtoMitigateHead-on-Pillow(HoP)Defects 139

NonwetOpen(NWO)/HangingBall 139

ComponentDefects 140

ReworkProcesses 140

ReworkPhilosophy 140

RemovalofBGAs 140

Replacement 141

LandPatternSiteDressing 141

FluxApplication 141

PasteApplication 142

ReworkIssues 142

Hot-AirSystemsforBGARework 142

LaserSystemsforBGARework 142

InfraredSystemsforBGARework 143

ProfileRequirements 143

RELIABILITY 144

ReliabilityFactorsforBGAAssemblies 144

CyclicStrain 144

Fatigue 144

Creep 145

CreepandFatigueInteraction 146

ReliabilityUnderMechanicalLoads 146

Shock 146

TransientBend 147

CyclicBend 147

Vibration 147

ContinuousAcceleration 147

DamageMechanismsandFailure

ofSolderAttachments 147

ComparisonofThermalFatigueCrackGrowthMechanisminSnAgCu(SAC)

vs.SnPbBGASolderJoints 148

Mixed-AlloySoldering 149

ForwardandBackwardCompatibility 149

Backward-CompatibilityOptionsforBGAsWithSACSolderBallsUsed

inSnPbSolderPasteReflow 151

Reballing 153

ReflowSolder 153

ReflowSolderUsingaSnPbProfile 153

ImplementationofBGAsWithLow-Ag

SACandNonSACBGABallAlloys 153

AssemblyManufacturingImpactsof

Pb-FreeBGABalls 154

SolderJointsandAttachmentTypes 154

GlobalExpansionMismatch 155

LocalExpansionMismatch 155

InternalExpansionMismatch 155

SolderAttachmentFailure 155

SolderAttachmentFailureClassification 155

FailureSignature1:ColdSolderJoint 156

FailureSignature2:NonsolderableLand 156

FailureSignature3:BallDrop 156

FailureSignature4:MissingBall 157

FailureSignature5:PrintedBoardand

BGAStackWarpage 157

FailureSignature6:MechanicalFailure 159

FailureSignature7:InsufficientReflow 160

CriticalFactorsImpactingReliability 160

PackageTechnology 160

Stand-OffHeight 161

PrintedBoardDesignConsiderations 162

ReliabilityofSolderAttachmentsof

CeramicGridArrays(CGAs) 162

Pb-FreeSolderingofBGAs 163

Pb-FreeAlloySelection 163

RecommendationsforAlloyswithAg

ContentNearOnePercent 164

SolderJointReliability 164

ManagingtheChangetoaLow-AgBall

Alloy 164

BoardDesignConsiderations 164

BGALandPatternDesigns 164

ComponentPlacement 164

AppearanceofPb-FreeBGASolder

Joints 165

DesignforReliability(DfR)Process 165

ValidationandQualificationTests 166

ScreeningProcedures 166

SolderJointDefects 166

ScreeningRecommendations 166

AcceleratedReliabilityTesting 166

PROCESSTROUBLESHOOTING 167

Solder-Mask-Defined(SMD)BGAConditions 167

Solder-Mask-Defined(SMD)andNon-

Solder-Mask-Defined(NSMD)Lands 167

Solder-Mask-Defined(SMD)Landon

ProductPrintedBoard 167

Solder-Mask-Defined(SMD)BGA

Failures 168

Over-CollapseBGASolderBall

Conditions 168

BGABallShapeWithoutHeatSlug

500μmStand-OffHeight 168

BGABallShapewithHeatSlug375μm

Stand-OffHeight 169

BGABallShapewithHeatSlug300μm

Stand-OffHeight 169

CriticalSolderPasteConditions 169

VoidDeterminationThroughX-Ray

andCross-SectionTransmission 169

VoidsandUnevenSolderBalls 170

BGAWarpage 170

BGAWarpage 170

SolderJointOpensDuetoInterposer

Warpage 171

SolderJointConditions 171

AcceptableSolderCondition 171

SolderBallswithExcessiveOxide 172

Dewetting 172

Nonwetting 172

IncompleteJoiningDuetoLandContamination 173

DeformedSolderBall 173

DeformedSolderBall–Dynamic

Warping 173

InsufficientSolderandFluxforProper

JointFormation 174

ReducedTerminationContactArea 174

SolderBridging 174

IncompleteSolderReflow 175

MissingSolder 175

NonwetOpen(NWO) 176

Head-on-Pillow(HoP)SolderJoint 176

APPENDIXAProcessControlCharacterizationto

ReducetheOccurrenceofVoids 177

ProcessCharacterization 178

Fine-PitchBGAs(FBGAs) 180

Via-in-LandDesigninFine-Pitch

BGAs(FBGAs) 181

APPENDIXBAbbreviationsandAcronyms 183

Tables

Table3-1 MultidieModule(MDM)Definitions 5

Table3-2 NumberofConductorsvs.ArraySizeon

TwoLayersofCircuitry 6

Table3-3 ListofIPCStandardsRelatedtoPadCratering 13

Table4-1 JEDECStandardJEP95-1/5Allowable

BallDiameterVariationsforFBGA 22

Table4-2 BallDiameterSizesforPlasticBGAs(PBGAs) 23

Table4-3 BallDiameterSizesforDie-SizeBGAs(DSBGAs) 23

Table4-4 LandPatternDesign 24

Table4-5 Land-to-BallCalculationsforBGA

Packages(mm) 25

Table4-6 ExamplesofJEDEC-RegisteredBGAOutlines 25

Table4-7 Pb-FreeAlloyVariations 26

Table4-8 ColumnGridArray(CGA)LandSizeApproximation 33

Table4-9 ColumnGridArray(CGA)AlloyandConstructionStyles 33

Table4-10 IPC-4101FR-4PropertySummaries–IllustrationsofSpecificationSheetsofMaterialsProjectedtoBetterWithstand

Pb-freeAssembly 40

Table4-11 TypicalPropertiesofCommonDielectricMaterialsforBGAPackageSubstrates 41

Table4-12 ControlledCoplanarityPerBallSize 44

Table4-13 MoistureClassificationLevelandFloor

Life 45

Table5-1 KeyAttributesforVariousPrintedBoardSurfaceFinishes 49

Table5-2 EvaluationViaFilling/Encroachment

BasedonSurfaceFinishProcess 56

Table5-3 ViaFillOptions 58

Table6-1 NumberofConductorsBetweenSolderLands–1.27mmPitchBGA

(0.75mmBallDiameter) 60

Table6-2 NumberofConductorsBetweenSolderLands–1mmPitchBGA

(0.60mmBallDiameter) 60

Table6-3 NumberofConductorsBetweenSolderLands–0.80mmPitchBGA

(0.50mmBallDiameter) 60

Table6-4 NumberofConductorsBetweenSolderLands–0.65mmPitchBGA

(0.40mmBallDiameter) 60

Table6-5 NumberofConductorsBetweenSolderLands–0.50mmPitchBGA

(0.30mmBallDiameter) 60

Table6-6 MaximumSolderLandtoPitch

Relationship(mm) 61

Table6-7 EscapeStrategiesforFullArrays 68

Table6-8 ConductorandSpaceWidthfor

DifferentArrayPitches 68

Table6-9 EffectsofMaterialTypeon

Conduction 82

Table6-10EmissivityRatingsforCertain

Materials 83

Table6-11InteractionBetweenBGAPackagingTechnologies 86

Table7-1RecommendationsforSolderPowderTypeforDifferentPitchestoAchieveGoodSolderPasteRelease

(S/PRatio>4.2) 87

Table7-2 StencilThicknessesPerBGAPitch 87

Table7-3 ProsandConsofCommonStencilTechnologiesandOptions 89

Table7-4 Fine-PitchBGA(FBGA)Printing

Options 90

Table7-5 ExampleofSolderPasteVolumeRequirementsforCeramicArray

Packages 92

Table7-6 ProfileComparisonBetweenSnPb

andSACAlloys 95

Table7-7 InspectionUsageApplication

Recommendations 110

Table7-8 FieldofViewforInspection 118

Table7-9 VoidClassification 126

Table7-10 ExamplesofSuggestedVoid

Protocols 129

Table7-11 Ball-to-VoidSizeImage–Comparisons

forVariousBallDiameters 130

Table7-12 ReworkProcessTemperatureProfiles

forSnPbAssembly 143

Table7-13 ReworkProcessTemperatureProfiles

forPb-FreeAssemblies 143

Table8-1 TypesofPb-freeAssemblies 149

Table8-2 TypicalStand-OffHeightsforBGAs 161

Table8-3 MeltingPoints,AdvantagesandDisadvantagesofCommonSolder

Alloys 163

TableA-1 CorrectiveActionIndicatorforLandsUsedWith1mm,

1.27mmand1.5mmPitch 179

TableA-2 CorrectiveActionIndicatorforLandsUsedWith0.5mm,

0.65mmor0.8mmPitch 180

TableA-3 CorrectiveActionIndicatorfor

Microvia-in-LandLandsUsedWith

0.3mm,0.4mmor0.5mmPitch 181

Figures

Figure3-1 BGAPackageManufacturingProcess 4

Figure3-2 MultidieModule(MDM)Type2S-L-WB 5

Figure3-3 ConductorWidth-to-PitchRelationship 7

Figure3-4 Wire-BondedBallGridArray(BGA) 7

Figure3-5 FlipChipBondedBallGridArray(BGA)...8Figure3-6 BGAWarpage 10

Figure3-7 ExamplesofPadCratering 12

Figure3-8 VariousPossibleFailureModesfora

BGASolderJoint 12

Figure3-9 CornerView(Left)andCross-SectionView(Right)ofaHead-on-Pillow(HoP)

SolderJointDefect 13

Figure3-10Cross-SectionViewofaHead-on-Pillow(HoP)OpenDefect 13

Figure3-11ExamplesofNonwetOpen(NWO)DefectsinSideViewand

Cross-SectionView 14

Figure4-1 TerminationTypesforAreaArray

Packages 17

Figure4-2 Board-on-Die(BOD)BGA

Construction 19

Figure4-3 TopofMoldedBoard-on-Die(BOD)

BGA 19

Figure4-4 FlipChip(BumpedDie)onaBGA

Substrate 20

Figure4-5 BGASolderJointsUsingSnPb–(A)andMixed-Metallurgy(B)

(Pb-FreeAlloyinaSnPbProcess)WithPartiallyMixedSnPbina

SACBall 21

Figure4-6 JEDECStandardFormatfor

Package-on-PackageComponents 25

Figure4-7 DynamicWarpagePlotwithTemperature

foraFlipChipBGAPackage 27

Figure4-8 Low-TemperatureAlloyswith

LiquidusTemperaturesBetween100°Cand200°Cand

WhichDoNotContainPb,CdorAu 27

Figure4-9 SnBiPhaseDiagram 28

Figure4-10TypicalMicrostructureofSnBiSolder

Alloy 28

Figure4-11PlasticBallGridArray(PBGA)

Package 29

Figure4-12Cross-SectionofaThermally

EnhancedCeramicBallGridArray

(CBGA)Package 29

Figure4-13CeramicBallGridArray(CBGA)PackagewithMoldedPolymer

Encapsulation 29

Figure4-14TypicalCeramicColumnGridArray

(CCGA)WithCuRibbonWrap 30

Figure4-15PlasticBGA(PBGA)withVarietyofColumns 31

Figure4-16TypicalSolderColumnwithCuRibbon

Wrap 31

Figure4-17SectionViewofSn10Pb90SolderColumnwithElectroplatedCuCovered

withSn60Pb40OuterLayer 31

Figure4-18SnPb-PlatedMicrocoil(Left)and

Au-PlatedMicrocoil(Right) 32

Figure4-19Au-PlatedMicrocoilSpringonColumnGridArray(CGA1152)CeramicIC

Package 32

Figure4-20MicrocoilSpringwithSAC305Fillet

onColumnGridArray(CGA)Package 32

Figure4-21MicrocoilSpring(ElectroplatedSn60Pb40)ColumnGridArray

(CGA1152)WithSn63Pb37Fillet 32

Figure4-22PolyimideFilm-BasedLead-B