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IPC/JEDECJ-STD-020F

Moisture/ReflowSensitivityClassificationfor

Non-hermeticSurfaceMountDevices(SMDs)

December2022

Supersedes:

IPC/JEDECJ-STD-

020EJanuary2015

IPC/JEDECJ-STD-020D.1March2008

IPC/JEDECJ-STD-020D

August2007IPC/JEDECJ-STD-020C

July2004

IPC/JEDECJ-STD-020B

July2002

IPC/JEDECJ-STD-020A

April1999

AjointstandarddevelopedbytheIPCPlasticChipCarrierCrackingTaskGroup(B-10a)andtheJEDECJC-14.1SubcommitteeonReliabilityTestMethodsforPackagedDevices.

Usersofthisstandardareencouragedtoparticipateinthedevelopmentoffuturerevisions.

Contact:

J-STD-020

October1996

JEDECJESD22-A112IPC-SM-786A

January1995IPC-SM-786

December1990

JEDEC IPC

SolidStateTechnologyAssociation 3000LakesideDrive,Suite309S3103North10thStreet,Suite240-South Bannockburn,Il60015-1249Arlington,VA22201-2107 Tel847615.7100

Tel703907.0026 Fax847615.7105

Fax703907.7501

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IPC/JEDECJ-STD-020F

MOISTURE/REFLOWSENSITIVITYCLASSIFICATIONFORNON-HERMETICSURFACEMOUNTDEVICES(SMDS)

Contents

Page

Purpose 1

Scope 1

Background 2

TermsandDefinitions 2

ApplicableDocuments 4

JEDEC1 4

IPC2 4

JointIndustryStandards2 4

Apparatus 5

TemperatureHumidityChambers 5

SolderReflowEquipment 5

FullConvection(Preferred) 5

Infrared 5

Ovens 5

Microscopes 5

OpticalMicroscope 5

AcousticMicroscope 5

ElectricalTest 6

WeighingApparatus(Optional) 6

BeadedThermocoupleTemperatureMeasurement 6

Classification/Reclassification 6

ClassificationTemperatures(Tc) 6

CompatibilitywithPb-free(SACandLTSAlloys)AssemblyRework 7

Reclassification 8

Procedure 9

SampleRequirements 9

Reclassification(QualifiedPackagewithoutAdditionalReliabilityTesting) 9

Classification/ReclassificationandRework 9

InitialElectricalTest 9

InitialInspection 9

Bake 9

MoistureSoak 10

Reflow 12

FinalExternalVisual 14

FinalElectricalTest 14

FinalAcousticMicroscopy 14

Criteria 15

FailureCriteriaafterReflowSimulation 15

CriteriaRequiringFurtherEvaluation 15

Delamination 15

MetalLeadframeDevices 16

LaminateBasedDevices(e.g.,BGA,LGA,etc.) 17

MoistureInducedBodyWarpageduringBoardAssemblyofLaminateBasedDevices 17

1stLevelInterconnectDevicessuchasFlipChip,WLPandBareDiewithPolymerLayers 17

Non-ICDevices 18

FailureVerification 18

Moisture/ReflowSensitivityClassification 18

OptionalWeightGain/LossAnalysis 18

WeightGain 18

AbsorptionCurve 19

ReadPointsforPlottingtheAbsorptionCurve 19

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IPC/JEDECJ-STD-020F

Contents(cont’d)

Page

DryWeight 19

MoistureSoak 19

Readouts;Absorption 20

DesorptionCurve 20

ReadPointsforPlottingtheDesorptionCurve 20

Baking 20

Readouts;Desorption 20

AdditionsandExceptions 20

AnnexA ClassificationFlow 21

AnnexB DifferencesBetweenRevisions 22

Figures Page

Figure1—ClassificationProfile(Nottoscale) 14

Figure2—ClassificationFlow 21

Tables Page

Table1—SnPbEutecticProcess–ClassificationTemperatures(TC) 6

Table2—Pb-free(SACAlloys)Process–ClassificationTemperatures(TC) 7

Table3—LTSAlloysProcess-ClassificationTemperatures(TC) 7

Table4—MoistureSensitivityLevels 11

Table5—ClassificationProfiles 13

Table6—DieAttachDelaminationCriteria 16

-ii-

IPC/JEDECJ-STD-020F

Page1

LONG-TERMSTORAGEGUIDELINESFORELECTRONICSOLID-STATEWAFERS,DICE,ANDDEVICES

(FromJEDECBoardBallotJCB-22-52,formulatedunderthecognizanceoftheJC-14.1CommitteeonReliabilityTestMethodsforPackagedDevices.)

Purpose

Thepurposeofthisstandardistoidentifytheclassificationlevelofnon-hermeticSMDsdesignedforsurfacemountassemblythataresensitivetomoisture-inducedstresssothattheycanbeproperlypackaged,stored,andhandledtoavoiddamageduringassemblysolderreflowattachmentand/orrepairoperations.

Thisstandardmaybeusedtodeterminewhatclassificationlevelshouldbeusedfornon-hermeticSMDqualification.Passingthecriteriainthistestmethodisnotsufficientbyitselftoprovideassuranceoflong-termreliability.TheMoistureSensitivityLevels(MSLs)ratinggeneratedforanSMDbythisdocumentisutilizedtodeterminethesoakconditionsforpreconditioningasperJESD22-A113andhowtheSMDcanbeproperlypackaged,stored,andhandledtoavoiddamageduringassemblysolderreflowattachmentand/orrepairoperationsasperJ-STD-033.

ForICdevicesthatmaybeprocesssensitive,pleaserefertoJ-STD-075todetermineifaPSL(ProcessSensitivityLevel)classificationisrequired.

Scope

Thisclassificationprocedureappliestoallnon-hermeticSMDs,which,becauseofabsorbedmoisture,couldbesensitivetodamageduringsolderreflow.ThetermSMDasusedinthisdocumentmeansplasticencapsulateddevicesandotherdevicesmadewithmoisture-permeablematerialsdesignedforsurfacemountassemblies.TheMSLclassificationlevelsareintendedtobeusedbySMDproducerstoinformusers(boardassemblyoperations)ofthelevelofmoisturesensitivityoftheirSMDs,andbyboardassemblyoperationstoensurethatproperhandlingprecautionsareappliedtomoisture/reflowsensitivedevices.IfnomajorchangeshavebeenmadetoapreviouslyqualifiedSMD,thismethodmaybeusedforreclassificationaccordingto4.3.

Thisstandardcannotaddressallpossibledevice,boardassemblyandproductdesigncombinations.However,thestandarddoesprovideatestmethodandcriteriaforcommonlyusedtechnologies.Whereuncommonorspecializeddevicesortechnologiesarenecessary,thedevelopmentoftheMSLratingshouldincludecustomeranddevicesupplierinvolvementandthecriteriashouldincludeanagreeddefinitionofproductacceptance.

SMDsclassifiedtoagivenmoisturesensitivitylevelbyusingproceduresorcriteriadefinedwithinanypreviousversionofJ-STD-020donotneedtobereclassifiedtothecurrentrevisionunlessachangeinclassificationlevelorahigherpeakclassificationtemperatureisdesired.

Iftheproceduresinthisdocumentareusedonpackageddevicesthatarenotincludedinthisspecification’sscope,thefailurecriteriaforsuchpackagesmustbeagreeduponbythedevicesupplierandtheirenduser.

IPC/JEDECJ-STD-020F

Page2

Scope(cont’d)

PastevaluationshaveshownthatSMDsthathavebeenclassifiedtoaMSLforSnPbeutectictemperaturesperthisdocumentmaybeattachedusingthesameMSLforaVaporPhasereflowprocessforSnPbeutectictemperaturesonly.CurrentlythereisnointenttoperformsimilarevaluationsforPb-freetemperatures.

Background

Thevaporpressureofmoistureinsideanon-hermeticpackageincreasesgreatlywhenthepackageisexposedtothehightemperatureofsolderreflow.Undercertainconditions,thispressurecancauseinternaldelaminationofthepackagingmaterialsfromthedieand/orleadframe/laminate,internalcracksthatmayormaynotextendtotheoutsideofthepackage,bonddamage,wirenecking,bondlifting,dielifting,thinfilmcracking,orcrateringbeneaththebonds.Inthemostseverecase,thestresscanresultinexternalpackagecracks.Thisiscommonlyreferredtoasthe“popcorn”phenomenonbecausetheinternalstresscausesthepackagetobulgeandthendelaminate/crackwithanaudible“pop.”SMDsaremoresusceptibletothisproblemthanthrough-holepartsbecausetheyareexposedtohighertemperaturesduringreflowsoldering.ThereasonforthisisthatthesolderingoperationmustoccuronthesamesideoftheboardastheSMD.Forthrough-holedevices,thesolderingoperationoccursundertheboardthatshieldsthedevicesfromthehotsolder.

TermsandDefinitions

Otherthanthefollowing,thedefinitionsoftermsusedinthisstandardareinaccordancewithIPC-T-50.Termsmarkedwithanasterisk(*)aredirectexcerptsofIPC-T-50andarereprintedhereforconvenience.

AcceleratedEquivalentSoakAsoakatahighertemperatureforashortertime(comparedtothestandardsoak),toprovideroughlythesameamountofmoistureabsorption.Seealso“Soak.”

*AcousticMicroscopeEquipmentthatcreatesanimageusingultrasoundtoviewaspecimen’ssurfaceorsubsurfacefeatures,includingdefectsanddamage.SeeJ-STD-035formoreinformation.

*AreaArrayPackageApackagethathasterminationsarrangedinagridonthebottomofthepackageandcontainedwithinthepackageoutline.

*ClassificationTemperature(Tc)ThemaximumbodytemperatureatwhichthedevicesupplierguaranteesthedeviceMSLasnotedonthecautionand/orbarcodelabel(perJ-STD-033).

CrackAseparationwithinabulkmaterial.Seealso“Delamination.”

*DamageResponseAllirreversiblechangescausedbyexposuretoareflowsolderingprofile.

Dead-Bug(Orientation)Theorientationofthepackagewiththeterminalsfacingup.

DelaminationAninterfacialseparationbetweentwomaterialsintendedtobebonded.Seealso“Crack”.

DownbondAreaAnareaforawirebondonthediepaddle,whosedimensionsequalthoseofasinglebondpadonthedie.

IPC/JEDECJ-STD-020F

Page3

TermsandDefinitions(cont’d)

FloorLifeTheallowabletimeperiodafterremovalfromamoisturebarrierbag,drystorage,ordrybakeandbeforethesolderreflowprocess.

NOTEForthepurposesofthisstandard,“Unlimited”floorlifeonlyreferstomoisture/reflowrelatedfailuresanddoesnottakeintoconsiderationotherfailuremechanismsorshelflifeissuesduetolongtermstorage.SeeJEP160.

FullBodyHotAirReworkTheprocessofheatingapackagebydirectingheatedgasatthepackagebodyinordertomeltonlythatpackage'ssolderconnections.

Live-Bug(Orientation)Theorientationofthepackagewhenrestingonitsterminals.

Manufacturer’sExposureTime(MET)Themaximumcumulativetimeafterbakethatdevicesmaybeexposedtoambientconditionspriortoshipmenttotheenduser.

Moisture/ReflowSensitivityClassificationThecharacterizationofadevice’ssusceptibilitytodamageduetoabsorbedmoisturewhensubjectedtoreflowsoldering.

MoistureSensitivityLevel(MSL)Aratingindicatingadevice’ssusceptibilitytodamageduetoabsorbedmoisturewhensubjectedtoreflowsoldering.

*PackageThicknessThedevicethicknessexcludingexternalterminals(balls,bumps,lands,leads)and/ornon-integralheatsinks.

Pb-free;lead-freeHavingamaximumlead(Pb)concentrationvalueof0.1%byweightinPCBsurfacefinishes,deviceterminalfinishes,bumporballmaterials,andattachmentsolders.

NOTE1 Pb-freeSACalloys:tin/silver/coppersoldersthathavealiquidus(uppermeltingpoint)intherangeof217℃to220℃.

NOTE2 LTS(LowTemperatureSolder)alloys:neareutectic-bismuthalloysthathavealiquidus(uppermeltingpoint)intherangeof150℃to170℃.

*PeakPackageBodyTemperature(TP)ThehighesttemperaturethatanindividualpackagebodyreachesduringMSLclassification.

ReclassificationTheprocessofassigninganewmoisturesensitivityleveltoapreviouslyclassifieddevice.

*SoakTheexposureofadeviceforaspecifiedtimeataspecifiedtemperatureandhumidity.Seealso“AcceleratedEquivalentSoak.”

Wire-BondSurfaceTheareawherewirebondsaretypicallyplaced.

IPC/JEDECJ-STD-020F

Page4

ApplicableDocuments

JEDEC1

JEP140BeadedThermocoupleTemperatureMeasurementofSemiconductorPackages

JEP160LongTermStorageGuidelinesforElectronicSolidStateWafers,Dice,andDevices

JESD22-A120TestMethodfortheMeasurementofMoistureDiffusivityandWaterSolubilityinOrganicMaterialsUsedinIntegratedCircuits

JESD22-A113PreconditioningProceduresofPlasticSurfaceMountDevicesPriortoReliabilityTesting

JESD22-B101ExternalVisual

JESD22-B108Co-planarityTestforSurface-MountSemiconductorDevicesJESD22-B112HighTemperaturePackageWarpageMeasurementMethodologyJESD47StressTestDrivenQualificationSpecification

JESD625RequirementsforHandlingElectrostaticDischargeSensitive(ESD)Devices

IPC2

IPC-TM-650TestMethodsManual2Microsectioning

Microsectioning-SemiorAutomaticTechniqueMicrosectionEquipment

JointIndustryStandards2

J-STD-033StandardforHandling,Packing,ShippingandUseofMoisture/ReflowSensitiveSurfaceMountDevices

J-STD-035AcousticMicroscopyforNonhermeticEncapsulatedElectronicDevices

J-STD-075ClassificationofPassiveandSolidStateDevicesforAssemblyProcesses3

1

2

3

/eia-technical-standards

IPC/JEDECJ-STD-020F

Page5

Apparatus

TemperatureHumidityChambers

Moisturechamber(s),capableofoperatingat85°C/85%RH,85°C/60%RH,60°C/60%RH,and30°C/60%RH.Withinthechamberworkingarea,temperaturetolerancemustbe±2°CandtheRHtolerancemustbe

±3%RH.

SolderReflowEquipment

FullConvection(Preferred)

Fullconvectionreflowsystemcapableofmaintainingthereflowprofilesrequiredbythisstandard.

Infrared

Infrared(IR)/convectionsolderreflowequipmentcapableofmaintainingthereflowprofilesrequiredbythisstandard.ItisrequiredthatthisequipmentuseIRtoheatonlytheairandnotdirectlyimpingeupontheSMDsundertest.

NOTEThemoisturesensitivityclassificationtestresultsaredependentuponthepackagebodytemperature(ratherthanthemountinglaminateand/orpackageterminaltemperature).

Ovens

Theovenusedforbakingshallbeventedandcapableofmaintainingtherequiredtemperaturesatlessthan5%RH.

Microscopes

OpticalMicroscope

OpticalMicroscope(40Xforexternaland100Xforcross-sectionexam,highermagnificationmightberequiredforverification).

AcousticMicroscope

TypicallyascanningacousticmicroscopewithC-ModeandThroughTransmissioncapability.Itshouldbecapableofmeasuringaminimumdelaminationof5%oftheareabeingevaluated.

NOTE1Theacousticmicroscopeisusedtodetectcrackinganddelamination.However,thepresenceofdelaminationdoesnotnecessarilyindicateapendingreliabilityproblem.Thereliabilityimpactofdelaminationmustbeestablishedforaparticulardie/packagesystem.

NOTE2RefertoIPC/JEDECJ-STD-035foroperationoftheacousticmicroscope.

Cross-Sectioning

Micro-sectioningequipmentasrecommendedperIPC-TM-650,Method2.1.1andMethodorotherapplicabledocument.

IPC/JEDECJ-STD-020F

Page6

ElectricalTest

Electricaltestequipmentwithcapabilitiestoperformappropriatetestingondevices.

WeighingApparatus(Optional)

Apparatuscapableofweighingthepackagetoaresolutionof1microgram.Thisapparatusmustbemaintainedinadraft-freeenvironment,suchasacabinet.Itisusedtoobtainabsorptionanddesorptiondataonthedevicesundertest(see11).

BeadedThermocoupleTemperatureMeasurement

RefertoJEP140forguidanceonprocedurestoaccuratelyandconsistentlymeasurethetemperatureofdevicesduringexposuretothermalexcursions.JEP140guidelineapplicationscaninclude,butisnotlimitedto,temperatureprofilemeasurementinreliabilitytestchambersandsolderreflowoperationsthatareassociatedwithdeviceassemblytoprintedwiringboards(PWBs).

NOTEThemoisturesensitivityclassificationtestresultsaredependentuponthepackagebodytemperature(ratherthanthemountinglaminateand/orpackageterminaltemperature).

Classification/Reclassification

Referto7.3forguidanceonreclassificationofpreviouslyqualified/classifiedSMDs.

Engineeringstudieshaveshownthatthin,smallvolumeSMDsreachhigherbodytemperaturesduringreflowsolderingtoboardsthathavebeenprofiledforlargerdevices.Therefore,technicaland/orbusinessissuesnormallyrequirethin,smallvolumeSMDs(referenceTable1andTable2)tobeclassifiedathigherreflowtemperatures.Toaccuratelymeasureactualpeakpackagebodytemperatures,refertoJEP140forrecommendedthermocoupleuse.

ClassificationTemperatures(Tc)

PreviouslyclassifiedSMDsshouldonlybereclassifiedbythedevicesupplier.UsersshouldrefertothecautionlabelonthebagtodetermineatwhichreflowtemperaturetheSMDswereclassified.

Ifthedevicesupplieranduseragree,devicescanbeclassifiedattemperaturesotherthanthoseinTable1,Table2,andTable3.IfadifferentTcisused,thenthetemperatureusedshallbewrittenonthecautionlabelasdefinedinJ-STD-033.

Table1—SnPbEutecticProcess-ClassificationTemperatures(TC)

PackageThickness

Volumemm3

<350

Volumemm3

350

<2.5mm

235C

220C

2.5mm

220C

220C

IPC/JEDECJ-STD-020F

Page7

ClassificationTemperatures(Tc)(cont’d)

Table2—Pb-free(SACAlloys)Process-ClassificationTemperatures(TC)

PackageThickness

Volumemm3

<350

Volumemm3350-2000

Volumemm3

>2000

<1.6mm

260°C

260°C

260°C

1.6mm-2.5mm

260°C

250°C

245°C

>2.5mm

250°C

245°C

245°C

Table3—LTSAlloysProcess-ClassificationTemperatures(TC)

AllPackageThickness

AllVolume(mm3)

190°C

Package“volume”excludesexternalterminals(e.g.,balls,bumps,lands,leads)and/ornon-integralheatsinks.Packagevolumeincludestheexternaldimensionsofthepackagebody,regardlessifithasacavityorisapassivepackagestyle.

Atthediscretionofthedevicesupplier,butnottheboardassembler/user,themaximumpeakpackagebodytemperature(Tp)canexceedthevaluesspecifiedinTable1orTable2.TheuseofahigherTpdoesnotchangetheclassificationtemperature(Tc).

Themaximumpeakpackagebodytemperaturereachedduringreflowdependsonpackagethicknessandvolume.Theuseofconvectionreflowprocessesreducesthethermalgradientsbetweenpackages.However,thermalgradientsduetodifferencesinthermalmassofSMDsmaystillexist.

MoistureSensitivityLevels(MSLs)ofdevicesintendedforuseinaPb-freeassemblyprocessshallbeevaluatedusingthePb-freeclassificationtemperaturesandprofilesdefinedinTable2andTable6whetherornotPb-free.

SMDsclassifiedtoagivenmoisturesensitivitylevelbyusingProceduresorCriteriadefinedwithinanypreviousversionofJ-STD-020,JESD22-A112(rescinded),IPC-SM-786(rescinded)donotneedtobereclassifiedtothecurrentrevisionunlessachangeinclassificationlevelorahigherpeakclassificationtemperatureisdesired.

CompatibilitywithPb-free(SACandLTSAlloys)AssemblyRework

Pb-free(SACalloy)area-arraydevicesclassifiedperTable2shouldbecapableofassemblyreworkatamaximumof260℃(unlikeTable2formassreflow,maximumreworkassemblyappliesforallpackagedimensions)within8hoursofremovalfromdrystorageorbake,perJ-STD-033orforlongtermstoragepertheguidelinesofJEP160.DevicesthatdonotmeetthisPb-freeSACalloyassemblyreworkrequirementinadrystateorforwhichthedevicesupplierdoesnotsupporta260℃reworktemperatureshallhavetheirsafereworkpeaktemperaturespecifiedbythedevicesupplier.

Toverifythiscapabilityfordevicesclassifiedatatemperaturebelow260℃,asampleofthesizeper8.1.2shallbesoakedperlevel6conditions(seeTable4)usingatimeonlabel(TOL)of8hoursandsubjectedtoasinglereflowcyclewithTpofnotlessthan260℃.Alldevicesinthesampleshallpasselectricaltestandhaveadamageresponse(per9.1and9.2)notgreaterthanthatobservedforthesamepackageatitsratedMSL.Reworkcompatibilityverificationisnotrequiredfordevicesinarea-arraypackagesratedat260℃.

IPC/JEDECJ-STD-020F

Page8

CompatibilitywithPb-free(SACandLTSAlloys)AssemblyRework(cont’d)

Reworkcompatibilityverificationisnotrequiredforperipheralleadedmetalleadframepackagesthatdonotrequirefullbodyhotairrework,butmayberequiredfordevicesinmulti-rowQFNpackagesandQFNswithmultipleexposedpads.

Reworkcompatibilityverificationisnotrequiredforarea-arraydevicesqualifiedforLTSalloyassembly,unlessthedevicesupplierhasstatedthattheLTSAlloyProcesspeakreflowtemperatureforthedeviceisbelow190°CasrequiredperTable3.

Reclassification

IfnomajorchangeshavebeenmadetoapreviouslyqualifiedSMD,thismethodmaybeusedforreclassificationtoanimprovedlevel(i.e.,longerfloorlife)atthesamereflowtemperature.Thereclassificationlevelcannotbeimprovedbymorethanonelevelwithoutadditionalreliabilitytesting.ReclassificationtoMSL1requiresadditionalreliabilitytesting.

SMDpreviouslyclassifiedtoaMSLandclassificationtemperature(Tc)maybereclassifiedifthedamageresponse(e.g.,delamination/cracking)atthemoresevereconditionforitemslistedin9.1and9.2islessthan,orequalto,thedamageresponseattheoriginalclassificationcondition.

IfnomajorchangeshavebeenmadetoapreviouslyqualifiedSMD,thismethodmaybeusedforreclassificationatahigherreflowtemperatureprovidingthemoisturelevelremainsthesameordegradestoamoresensitivelevel.

NoSMDsclassifiedasmoisturesensitivebyanypreviousversionofJ-STD-020,JESD22-A112(rescinded),orIPC-SM-786(rescinded)maybereclassifiedasnon-moisturesensitive(MSL1)withoutadditionalreliabilitystresstesting(e.g.,JESD22-A113andJESD47orthesemiconductordevicesupplier’sin-houseprocedures).

Tominimizetesting,theresultsfromagivenSMDmaybegenericallyacceptedtocoverallotherdeviceswhicharemanufacturedinthesamepackage,usingthesamepackagingmaterials(e.g.,dieattach,moldcompound,and/ordiecoating,etc.),withthedieusingthesamewaferfabricationtechnology,andwithdiepaddimensionsnotgreaterthanthosequalified.

Thefollowingattributescouldaffectthemoisturesensitivityofadeviceandmayrequirereclassification:

Dieattachmaterial/process.

Numberofpins.

Encapsulation(moldcompoundorglobtop)material/process.

Diepadareaandshape.

Bodysize.

Passivation/diecoating.

Leadframe,laminate,and/orheatspreaderdesign/material/finish.

Diesize/thickness.

Waferfabricationtechnology/process.

Interconnect.

Leadlocktapingsize/locationaswellasmaterial.

IPC/JEDECJ-STD-020F

Page9

Procedure

Therecommendedprocedureistostarttestingatthelowestmoisturesensitivityleveltheevaluationpackageisreasonablyexpectedtopass(basedonknowledgeofothersimilarevaluationpackages).

Inthecaseofequipmentmalfunction,operatorerror,orelectricalpowerloss,engineeringjudgmentshallbeusedtoensurethattheminimumintent/requirementsofthisspecificationaremet.

SampleRequirements

Reclassification(QualifiedPackagewithoutAdditionalReliabilityTesting)

ForaqualifiedSMDbeingreclassifiedwithoutadditionalreliability,selectaminimumsampleof22devicesforeachMSLtobetested.Aminimumoftwononconsecutiveassemblylotsmustbeincludedinthesamplewitheachlothavingapproximatelythesamerepresentation.Sampledevicesshallhavecompletedallmanufacturingprocessingrequiredpriortoshipment.SamplegroupsmayberunconcurrentlyononeormoreMSLs.

Classification/ReclassificationandRework

Selectaminimumsampleof11devicesforeachMSLtobetested.Aminimumoftwononconsecutiveassemblylotsmustbeincludedinthesamplewitheachlothavingapproximatelythesamerepresentation.Sampledevicesshallhavecompletedallmanufacturingprocessesrequiredpriortoshipment.SamplegroupsmayberunconcurrentlyononeormoreMSLs.Testingmustbecontinueduntilapassinglevelisfound.

SMDsshouldnotbereclassifiedbytheuserunlessapprovedbythedevicesupplier.

InitialElectricalTest

Testappropriateelectricalparameters(e.g.,datasheetvalues,inhousespecifications,etc.).Replaceanydevice,whilemaintainingthesamplerequirementsof8.1.2,whichfailtomeettestedparameters.

InitialInspection

Performanexternalvisual(at40X)andacousticmicroscopeexaminationonalldevicestoestablishabaselineforthedelaminationcriteriain9.2.1.

Note:Thisstandarddoesnotconsiderorestablish