Root-Cause Failure Analysis of Electronics - SMTA

Root-Cause Failure Analysis of ElectronicsBhanu SoodTest Services and Failure Analysis (TSFA) LaboratoryCenter for Advanced Life Cycle Engineering (CALCE)University of MarylandCollege Park, MD 20742Center for Advanced Life Cycle EngineeringSMTA Philadelphia, March 14, 20131bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Content DisclaimerThe information contained in this packet is designed to be accurate and authoritative in regardsto the subject matter covered. However, it is provided with the understanding that the provider isnot engaged in rendering legal, accounting, engineering, or other professional services. It isintended to be used for educational purposes only. Individual presenters, their respectiveorganizations and Center for Advanced Life Cycle Engineering (CALCE) disclaim anyresponsibility or liability for this material and are not responsible for the use of this informationoutside of its educational purpose.Copyright NoticeThe information contained within this packet has been compiled by theUniversity of Maryland, CALCEReplication rights of all information is retained by individual presenters, their respectiveorganizations and CALCE.Copyright © 2013 CALCE and the University of Maryland. All rights reserved.

What are the Biggest Headaches?• CALCE Laboratory Servicesreviewed 150 root-causeanalyses of failures duringqualification or at a customersite– Representative of over 80different companies.• These failures werecategorized by failure site– PCB and capacitor issuesaccounted for over 50% ofthese failures.Center for Advanced Life Cycle EngineeringInterconnects/Solder Joints 13%2PEM 21%bpsood@calce.umd.edu301-405-3498Other Sites 7%Connectors 3%Capacitors 30%Printed Board 26%University of MarylandCopyright © 2013Where there are Failures… There Are Costs . . .• Costs to the Manufacturero Time-to-market can increaseo Warranty costs can increaseo Market share can decrease. Failures can stain thereputation of a company, and deter new customers.o Claims for damages caused by product failure can increase• Costs to the Customero Personal injuryo Loss of mission, service or capacityo Cost of repair or replacemento Indirect costs, such as increase in insurance, damage toreputation, loss of market shareCenter for Advanced Life Cycle Engineering3bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Type of BusinessWhat is the Cost of Failure?*Retail Brokerages $6,450,000Credit Card Sales Authorization $2,600,000Home Shopping Channels $113,750Catalog Sales Centers $90,000Airline Reservation Centers $89,500Cellular Service Activations $41,000Package Shipping Services $28,250Online Network Connect Fees $22,250ATM Service Fees $14,500Supermarkets $10,000Lost Revenue per HourOutline• Definitions• Root cause failure analysis– RCA Steps• Case Studies• Closing remarks* - 1999 dollarsCenter for Advanced Life Cycle Engineering4bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering5bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Failure DefinitionsFailure AnalysisFailureFailure ModeFailure SiteFailure MechanismA product no longer performs the function for which itwas intendedThe effect by which a failure is observed.The location of the failure.The physical, chemical, thermodynamic or other processthat results in failure.Failure ModelLoadQuantitative relationship between lifetime or probabilityof failure and loadsApplication/environmental condition needed (electrical,thermal, mechanical, chemical...) to precipitate a failuremechanism.Center for Advanced Life Cycle Engineering6bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering7bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Classification of FailuresFailure Mechanism Identification• It is helpful to distinguish between two key classes offailure mechanism:– overstress: use conditions exceed strength of materials; oftensudden and catastrophic– wearout: accumulation of damage with extended usage or repeatedstress• It is also helpful to recognize early life failures:– infant mortality: failures occurring early in expected life; should beeliminated through process control, part selection andmanagement, and quality improvement proceduresOverstress MechanismsMechanicalThermalElectricalRadiationChemicalYield, Fracture,Interfacial de-adhesionGlass transition (T g)Phase transitionDielectric breakdown,Electrical overstress,Electrostatic discharge,Second breakdownSingle event upsetContaminationWearout MechanismsMechanicalThermalElectricalRadiationChemicalFatigue,Creep, WearStress driven diffusionvoiding (SDDV)TDDB, Electromigration,Surface chargespreading, Hot electrons,CAF, Slow trappingRadiation embrittlement,Charge trapping inoxidesCorrosion,Dendrite growth,Depolymerization,Intermetallic GrowthCenter for Advanced Life Cycle Engineering8bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering9bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

What Causes Products to Fail?• Generally, failures do not “just happen.”• Failures may arise during any of the following stages of aproduct’s life cycle:What is Root Cause Analysis?Root Cause analysis has four major objectives:• Verify that a failure occurred;• Determine the symptom or the apparent way a part has failed(the mode);• Determine the mechanism and root cause of the failure;• Recommend corrective and preventative action.The damage (failure mode) may not be detected until a laterphase of the life cycle.Center for Advanced Life Cycle Engineering10bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013While generally synonymous, “Failure analysis” iscommonly understood to include all of this exceptdetermination of root cause.Center for Advanced Life Cycle Engineering11bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013What is a Root CauseThe root cause is the most basic causal factor or factorsthat, if corrected or removed, will prevent therecurrence of the situation.*The purpose of determining the root cause (s) is to fix theproblem at its most basic source so it doesn’t occur again,even in other products, as opposed to merely fixing afailure symptom. Identifying root causes is the key topreventing similar occurrences in the future.Root Cause Analysis isDifferent from Troubleshooting• Troubleshooting is generally employed toeliminate a symptom in a given product, or toidentify a failed component in order to effect arepair.• Root cause analysis is dedicated to finding thefundamental reason why the problem occurred inthe first place, to prevent future failures.* ABS Group, Inc., Root Cause Analysis Handbook, A Guide to EffectiveIncident Investigation, ABS Group, Inc., Risk & Reliability Division,Rockville, MD, 1999.Center for Advanced Life Cycle Engineering12bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering13bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

From Symptoms to Root Causes• Symptoms are manifestations of a problem; signs indicatingthat a failure exists.– Example: a symptom of printed circuit board failure could be themeasurement of open circuits after fabrication.• An apparent cause (or immediately visible cause)is the superficial reason for the failure.– Example: the apparent cause of open circuits could be that traceshave discontinuities which result in open circuits.• Root Cause is the most basic casual factor(s).– Example: the root cause could arise during the manufacturingprocess if the circuit boards are stacked improperly, resulting inscratches to circuit traces. Another possible root cause could be thepresence of contaminants during the copper trace etching process,which resulted in discontinuities in the traces.Root Cause Analysis• Root cause analysis is a methodology designed to help:1) Describe WHAT happened during a particular occurrence,2) Determine HOW it happened, and3) Understand WHY it happened.• Only when one is able to determine WHY an event or failureoccurred, will one be able to determine corrective measures, andover time, the root causes identified can be used to target majoropportunities for improvement.• Uncovering ROOT CAUSE may require 7 iterations of “Why?”Center for Advanced Life Cycle Engineering14bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering15bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Preplanning: Establish Root Cause Culture with Management Support and Responsibilities Policy/procedures for notification Trained investigation team Hypothesization Tools Classification system Analysis procedures Risk AnalysisAlert / Notification : Begin Investigation Secure evidence (data collection) Assess immediate cause(s) Interview witnessesHypothesize causes using tools such as Ishikawa (fishbone) diagram, and failure modes, mechanisms,and effects analysis (FMMEA)Identify Root Cause (s)Identify Restart CriteriaDevelop Corrective ActionsRoot Cause Analysis ProcessTheIncident!Analyze and Interpret EvidenceReview documents and Conduct physicalprocedures, and check evaluationagainst standards (core of the FA process)ValidatehypothesesImplement CorrectiveActions and/or DocumentResolutionsConduct a Follow-up Audit,Confirm Effectiveness, thenCritique and Modify ProcessA Cause and Effect Diagram- Electrostatic Discharge in a Semiconductor Device -WAFERENVIRONMENTFootwearPeopleClothesAirFlowHumidityScalingGeometryCDsTestingLayoutFloorsWorkAreaGroundingToolsFurnitureTemperatureProtectiveStructuresShapeMaterialSizeElectricalDESIGN PropertiesBrushes BlowersEquipmentTypeOvens SprayToolsMaterialsSystemsPRODUCTIONTOOLSEnergySourcesFrictionHandlingDisciplineHandlingTrainingProcessAssemblyLeadFramePackageMaterialDieCarriersPackagedWaferCommitmentManagementProblemRecognitionWaferProcessingMANUFACTURINGELECTROSTATICDISCHARGECenter for Advanced Life Cycle Engineering16bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering17bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

CertificationA Cause and Effect Diagram- PCBA Delamination -Assembly Process/MethodtimeCuring TemptimeWarpageBow & TwistBookingalloyReflowprofile No. of passesCooling RateWorking InstructionsOJTAbilityTrainingManHandlingKnowledgeCenter for Advanced Life Cycle EngineeringPressureTemperatureStacking upMethod18Pre-pregHardenerBlankMetallizationtimemethodtemperatureWaveSolderProfileOperatingConditionsCopperThicknessMaterialBinderHumidityReinforceMaterialSoldermaskLifeCycleDesignWarpageQualityNo. of layersEpoxy ResinSystemAcceleratorAssemblyProcessEpoxy/ResinSystemPre-pregbpsood@calce.umd.edu301-405-3498Copper SheetSpecsStack upSequenceDimensionsPropertiesCTEDelaminationUniversity of MarylandCopyright © 2013General Approach Used for Failure Analysis• The overriding principle of failure analysis is to start with theleast destructive methods and progress to increasingly moredestructive techniques.• The potential for a nominally non-destructive technique tocause irreversible changes should not be underestimated.– For example, the simple act of handling a sample, or measuring aresistance, can cause permanent changes that could complicateanalysis further down the line.• Each sample and failure incidence may require a uniquesequence of steps for failure analysis. The process demandsan open mind, attention to detail, and a methodical approach.Center for Advanced Life Cycle Engineering19bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Example of Failure Analysis Process FlowOccurrence ofFailurePreservation of FailureNon-Destructive Analysisof FailureElectrical Test/Verification of Failure/Classification of Failure ModeDeprocessing (DestructivePhysical AnalysisIdentification of Failure SiteIntermittentReliability Test/Simulation ofFailure CircumstancesInvestigation of FailureOccurrence CircumstancesIn-Circuit EvaluationNon-Destructive Testing (NDT)• Visual Inspection• Optical Microscopy• X-ray imaging• X-ray Fluorescence Spectroscopy• Acoustic microscopy• HermeticityPhysical AnalysisHypothesis ofFailure MechanismRoot Cause DeterminationCorrective ActionVerification &DocumentationCenter for Advanced Life Cycle Engineering20bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering21bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

External Inspection• Visual inspection of external condition– differences from good samples• Detailed inspection: appearance, composition,damage, contamination, migration, abnormalities– Low power microscope– High power microscope– Scanning electron microscope– Surface chemical analysisElectrical Testing• Electrical characteristics/performance• DC test• Parametrics (current-voltage characteristic)• Simulated usage conditions• Electrical probingCenter for Advanced Life Cycle Engineering22bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering23bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Fault Isolation• Electrical Probing• Time Domain Reflectometry (TDR)• Electron Beam Testing– electron beam induced current (EBIC),– voltage contrast (VC),– cathodoluminescence (CL)• Emission Microscopy• Scanning Probe Microscopy• Thermal AnalysisDeprocessing:Destructive Physical Analysis (DPA)• Modification of specimen in order to revealinternal structures and analyze failure site. Mayinvolve:– Cross-sectioning and metallography– Decapsulation or delidding– Residual Gas Analysis for internal gasesCenter for Advanced Life Cycle Engineering24bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering25bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Physical Analysis of Failure SiteRoot Cause IdentificationVisual andlightmicroscopeexaminationof partCorrosionof leadsPartdeformationPackage cracksDamagedsolder jointsElectricaltesting ofcomponentandconnectorShortsOpensParametric shiftsContact resistanceScanningacousticmicroscopeand X-rayradiographPackagedelaminationPackage crackingWire sweepbroken wireDecapsulationthen opticalmicroscopeE-SEM, VC,and EBICWire fatigueDie crackingCorrosionSDDV andelectromigrationDie crackingor bond liftEOS/ESDDestructivecrosssection,E-SEM, andEDSIntermetallicgrowthSolder jointcracking andcoarseningPartdelaminationand crackingMechanicaltesting ofinternalcomponentsWire pullBond shearDie shear• Testing may be needed to determine the effect ofhypothesized factors on the failure.• A design of experiment (DoE) approach is recommendedto incorporate critical parameters and to minimize thenumber of tests.• This experimentation can validate a hypothesized rootcause.Center for Advanced Life Cycle Engineering26bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering27bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013IntroductionElectrical Shorting on a 480V RectifierAssembly Used in an UncontrolledAmbient EnvironmentsCenter for Advanced Life Cycle Engineering28bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013• Failures in a 480 Volt rectifier assembly were reported.Unit was removed from a field location. This assemblysuffered catastrophic damage to secondary side,including damage to solder mask, pin damage andpotential board damage.• CALCE inspected one failed and one non-failed fieldedassembly to determine the cause of failure. Steps in theanalysis:– Visual/optical inspection– Radiological inspection– Environmental Scanning Electron Microscopy (ESEM) andEnergy Dispersive Spectroscopy (EDS)Center for Advanced Life Cycle Engineering29bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Visual Inspection – Failed and Non-Failed AssembliesVisual InspectionFORMEX GK-10 insulationFailed Fielded Assembly10mmConnector PTHsPTH: Plated Through HolePCB: Printed Circuit BoardNon-failed Fielded Assembly10mmFailed Assembly – SecondaryInsideFailed Fielded Assembly - OutsidePCBInsulatorChassisConnectorCenter for Advanced Life Cycle Engineering30bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering31bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Optical Inspection – Failed Assembly(Secondary Side of PCB)20mmFailed Fielded AssemblyOVHMFailed Fielded AssemblyOVHMNon-FailedOVHMNon-FailedOVHMCenter for Advanced Life Cycle Engineering32bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering33OVHM: Oblique view high magbpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

E-SEM/EDS InspectionRegion 1Inspection of Regions Close to WashersFailedRegion 1Region 2AABSiCuSnPbOSiCuSnPbOCaRegion 2B• Washer from the marked region was removed and inspectedunder low power stereo microscope. The PCBs/solder mask wasalso inspected optically.• Corresponding washer from the non-failed board was alsoinspected.Center for Advanced Life Cycle EngineeringMn34bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013• The washers and PCBs were also inspected in ESEM and EDS.Center for Advanced Life Cycle Engineering35bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013FailedOptical Images – PCB/Solder MaskFailedFailedESEM Images of WashersNon-failedNon-failedNon-FailedCenter for Advanced Life Cycle Engineering36bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering37bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

FailedEDS Elemental Analysis of WashersESEM ImageFeCenter for Advanced Life Cycle EngineeringCaOPresence of calcium suggests presence of same debris material that wasobserved in other areas throughout the secondary surface.38SiZnbpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle EngineeringSummary and Conclusions• Region under the washer on the failed assembly contains residues that appear toadhere to the solder mask.– These residues appear to be in the form of islands around the PCB through-hole.– Similar region on the non-failed assembly did not contain the whitish residues.Debris observed on non-failed assembly appears to originate from the PCB throughhole (glass fiber and resin debris).• Particulate contaminant (andmoisture) may have trappedbetween the inner side of FORMEXGK-10 and secondary side of PCB– Created low impedance pathsacross pin pairs on the secondaryside of the board.• Energizing the circuit, withoutremoval or disrupting these lowimpedance paths may have caused acatastrophic failure on thesecondary side.39bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Failure Analysis of Schottky Diodes inD-67 PackageIntroduction• Schottky diodes are reported to be exhibiting electrical shorts in field. CALCEconducted the analysis on some failed (in field applications) and as-received(from customer stock).• Peak voltage is between 120V and 130V varying with load conditions. Diodesexperience peak currents of 90A.• Approach– Radiographic inspection (X-ray)– Dye penetrant testing of diodes from failed and non-failed assemblies– Chemical and mechanical decapsulation of selected samples– Optical inspection of decapsulated package– Environmental scanning electron microscopy (ESEM)– Energy dispersive spectroscopy (EDS) analysis for elemental identification ofmaterials.1 cmCenter for Advanced Life Cycle Engineering40bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering41bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Discunder dieDieHeat spreaderAttachConstruction Analysis - IMetal ClipMetal ConnectorDisc between clip and dietop, attached with solderCross-section ofthe Schottkydiode assembly• Attachmaterials•DieConstruction Analysis - IISolderSolderSolderMo DiscSolderDieMo DiscChemically decapsulated Schottky diodeChemically decapsulated Schottky diodeParts are chemically decapsulated using the process:1. Physically remove sleeve2. Immerse part in a beaker with 98% H 2 SO 4 , placed over 320°C hot plate3. Repeatedly rinse and re-immerse until molding compound is removed•MetalcomponentsCopper Heat SinkCenter for Advanced Life Cycle Engineering42bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering43bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Stock diodeX-ray Inspection Failed SampleFailed diodeDiode Investigation – IR ImagingLocalized Hotspots (IR Imaging)Damaged to the diode was observed with x-ray inspectionCenter for Advanced Life Cycle Engineering44bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle EngineeringLocalized Hotspot (IR Imaging)45bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Delamination at Die/EMC InterfaceConstruction Review – Stock SampleDelaminationDieDelaminationEDS elemental analysisshows the material iscomposed of Silver.• Four dies in the package, die size is 5mm × 5mm.• Fiducials are seen on 3 dies, under the molding compound (arrows).• Fiducials are Silver, as seen with EDS elemental analysis.Center for Advanced Life Cycle Engineering46bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering47bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 201362µm 60µmDistance from Die Edge - Fiducial60µmNon-failed Diode Assembly – Dye PenetrantInspectionExtent of dyepenetration61µm61µmFiducials are approximately 60µm from edge of the dieCenter for Advanced Life Cycle Engineering48bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013• After immersing and drying the diodes from non-failed assembly, the molding waspried open.• Optical inspection revealed dye penetration under the molding compound.• In the image on the right, the dye is seen to reach the edge of on one of the four dies.Center for Advanced Life Cycle Engineering49bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Conclusions• Given the presence of Silver on the samples,either as fiducial or as die surface coating, thereis an available source within the package forsilver migration.• In addition to presence of silver, a migrationprocess will also be accelerated by the following:1.Creation of a path by delamination between die edge andmolding compound – dye penetrant test provided indication ofpoor contact between molding compound and heat spreader,thus creating a path for moisture ingress, other paths may exist,and further investigation is required2.Absorption of moisture by the molding compound.Failure Analysis of MultilayerCeramic Capacitor (MLCC) withLow Insulation ResistanceCenter for Advanced Life Cycle Engineering50bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering51bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013MLCC Construction• Ceramic Dielectric– Typically comprised of compounds made withtitanium oxides‣ BaTiO 3(“X7R”) for this study• Electrodes– Base metal consisting of nickel (BME)‣ Precious metal consisting of silver/ palladium(PME)• End Termination– Standard termination consists of silver orcopper coated with nickel and tin‣ Flexible termination consists of a silver filledpolymer coated with nickel and tinRef: Kemet• A Temperature-Humidity-Bias(THB) test was performed for1766 hours at 85°C and 85% RH,at the rated voltage of 50V.• Capacitance, Dissipation Factor(DF) and Insulation Resistance(IR) were monitored during thetest.• A 1 MΩ resistor was placed inseries with each of the MLCCs.• The MLCCs were size 1812 andsoldered to an FR-4 printedcircuit board using eutectic tinleadsolder.Loading Conditions:Temperature-Humidity-BiasData Acquisition,Temp.LCR Meter: C, DFHigh Resistance Meter: IRCenter for Advanced Life Cycle Engineering52bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering53bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

1.0E+09IR Test Data for FailedFlexible Termination MLCCsTHB Failure Analysis Methodology for Biased MLCCsInsulation Resistance (Ohms)1.0E+081.0E+071.0E+061.0E+050 200 400 600 800 1000 1200 1400 1600 1800Time (Hours)Center for Advanced Life Cycle Engineering54bpsood@calce.umd.edu301-405-3498Cap 24Cap 26Cap 62Cap 66University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering• A Buehler MPC 2000 (with 9 micron lappingfilm) was used to cross-section the MLCC.• The MLCC (on a PCB) was mounted to afixture using wax.• Wires were soldered to the board, along witha 1 kΩ series resistor.• Resistance was monitored with a multimeteras the sample was moved ~5 microns at atime while checking for a resistance change.• Epoxy was added under the part to preventbuildup of metal debris, which could causean inaccurate resistance value.55bpsood@calce.umd.edu301-405-3498OHMUniversity of MarylandCopyright © 201345 µmMetal Migration Between Electrodes100EDS Line Scan Showing Silver andPalladium in Area of the Metallic BridgeAgPdCounts8060electrodeelectrode4020AgPdBackgroundlevel of Ag010 Distance [µm] 20 3020 µmOptical Micrographs of Cross-sectionSEM Image of Cross-sectionCenter for Advanced Life Cycle Engineering56bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering57bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

EDS Map Showing Silver Migration andVoiding in CeramicFailure Mechanism• Metal migration was found in several of the failedMLCCs.• Voids in the ceramic, without silver or palladium, werealso found close to the conduction path.• The failure mechanism was electrochemical comigrationof silver and palladium, aided by porosity inthe dielectric.Center for Advanced Life Cycle Engineering58bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering59bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Restart Criteria• Failures with severe consequences (e.g., safety) mayrequire processes (e.g., manufacturing, distribution) to beinterrupted after discovery of the failure.• Depending upon the identified root cause, processesinterrupted may be re-started if corrective action (s) canbe implemented that will prevent the recurrence of thefailure, or sufficiently minimize its impact.Corrective Actions• Many of the failures having a direct impact on productionrequire immediate corrective actions that will minimizedowntime.• Although many immediate actions may correct symptoms,– temporary solutions may not be financially justifiable over the “longhaul”; and– there is a large risk that a temporary solution may not solve theproblem.Center for Advanced Life Cycle Engineering60bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering61bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

VerificationVerification of the corrective action includes:• verifying the approval and implementation of the correctiveaction;• verifying a reduction in the incidence of failures;• verifying the absence of new failures associated with thefailure sites, modes, and mechanisms identified during thefailure analysis.Root Cause Analysis ReportThe report should include the following information:1. Incident summary2. History and conditions at the time of failure3. Incident description4. Cause evaluated and rationale5. Immediate corrective actions6. Causes and long-term corrective actions7. Lesson learned8. References and attachments9. Investigating team description10.Review and approval team description11.Distribution listCenter for Advanced Life Cycle Engineering62bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering63bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Failures of a Failure Analysis Program• Shutting down the malfunctioning equipment• Refusing to recognize that a failure can or does exist• Assuming an apparent cause to be the root cause• Determining the failure cause by assumption• Collecting insufficient information and ending ananalysis before it is complete• Discarding failed parts• No documentationFurther Suggested Reading• Journal of Failure Analysis and Prevention, ASMInternational.• Electronic Device Failure Analysis (EDFA) Journal, ASMInternational.• Engineering Failure Analysis, Elsevier.• Electronic Failure Analysis Handbook, Perry L. Martin,McGraw-Hill Professional.• Microelectronics Failure Analysis Desk Reference (Book +CD set) [Hardcover], EDFAS Desk Reference Committee.Center for Advanced Life Cycle Engineering64bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering65bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013

Center for Advanced Life Cycle EngineeringCALCE Introduction• The Center for Advanced Life Cycle Engineering (CALCE)formally started in 1984, as a NSF Center of Excellence insystems reliability.• One of the world’s most advanced and comprehensive testing andfailure analysis laboratories• Funded at $6M by over 150 of the world’s leading companies• Supported by over 100 faculty, visiting scientists and researchassistants• Received NSFInnovationAward andNDIASystemsEngineeringExcellence Award in 200966bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013• Alcatel-Lucent• Aero Contol Systes• Agilent Technologies• American Competitiveness Inst.• Amkor• Arbitron• Arcelik• ASC Capacitors• ASE• Astronautics• Atlantic Inertial Systems• AVI-Inc• Axsys Engineering• BAE Systems• Benchmark Electronics• Boeing• Branson Ultrasonics• Brooks Instruments• Buehler• Capricorn Pharma• Cascade Engineering• Celestical International• Channel One International• Cisco Systems, Inc.• Crane Aerospace & Electronics• Curtiss-Wright Corp• CDI• De Brauw Blackstone Westbroek• Dell Computer Corp.• DMEA• Dow Solar• DRS EW Network Systems, Inc.• EIT, Inc.• Embedded Computing & Power• EMCORE Corporation• EMC• EADS -France• Emerson Advanced Design CtrCALCE Research Funding (over $6M): 2012• Emerson Appliance Controls• Emerson Appliance Solutions• Emerson Network Power• Emerson Process Management• Engent, Inc.• Ericsson AB• Essex Corporation• Ethicon Endo-Surgery, Inc.• Exponent, Inc.• Fairchild Controls Corp.• Filtronic Comtek• GE Healthcare• General Dynamics, AIS & Land Sys.• General Motors• Guideline• Hamlin Electronics Europe• Hamilton Sundstrand• Harris Corp• Henkel Technologies• Honda• Honeywell• Howrey, LLP• Intel• Instituto Nokia de Technologia• Juniper Networks• Johnson and Johnson• Johns Hopkins University• Kimball Electronics• L-3 Communication Systems• LaBarge, Inc• Lansmont Corporation• Laird Technologies• LG, Korea• Liebert Power and Cooling• Lockheed Martin Aerospace• Lutron Electronics• Maxion Technologies, Inc.• MicrosoftCenter for Advanced Life Cycle Engineering67• Motorola• Mobile Digital Systems, Inc.• NASA• National Oilwell Varco• NAVAIR• NetApp• nCode International• Nokia Siemens• Nortel Networks• Nordostschweizerische KraftwerkeAG (NOK)• Northrop Grumman• NTSB• NXP Semiconductors• Ortho-Clinical Diagnostics• Park Advanced Product Dev.• Penn State University• PEO Integrated Warfare• Petra Solar• Philips• Philips Lighting• Pole Zero Corporation• Pressure Biosciences• Qualmark• Quanterion Solutions Inc• Quinby & Rundle Law• Raytheon Company• Rendell Sales Company• Research in Motion• Resin Designs LLC• RNT, Inc.• Roadtrack• Rolls Royce• Rockwell Automation• Rockwell Collins• Saab Avitronics• Samsung Mechtronics• Samsung Memorybpsood@calce.umd.edu301-405-3498• S.C. Johnson Wax• Sandia National Labs• SanDisk• Schlumberger• Schweitzer Engineering Labs• Selex-SAS• Sensors for Medicine and Science• SiliconExpert• Silicon Power• Space Systems Loral• SolarEdge Technologies• Starkey Laboratories, Inc• Sun Microsystems• Symbol Technologies, Inc• SymCom• Team Corp• Tech Film• Tekelec• Teradyne• The Bergquist Company• The M&T Company• The University of Michigan• Tin Technology Inc.• TÜBİTAK Space Technologies• U.K. Ministry of Defence• U.S. Air Force Research Lab• U.S. AMSAA• U.S. ARL• U.S. Naval Surface Warfare Center• U.S. Army Picatinney/UTRS• U.S. Army RDECOM/ARDEC• Vectron International, LLC• Vestas Wind System AS• Virginia Tech• Weil, Gotshal & Manges LLP• WesternGeco AS• Whirlpool Corporation• WiSpry, Inc.• Woodward GovernorUniversity of MarylandCopyright © 2013CALCE Facilities and Capabilities• Consumer and mobile products• Telecommunications and computer systems• Energy systems (generation/storage/distr)• Industrial systems• Transportation systems• Aerospace systems• Medical systems• Military systems• Equipment manufacturers• Government Labs and AgenciesEnvironmental/Accelerated TestingTemperature‐Humidity ChambersHALT Temperature‐Vibration ChamberThermal Shock Chambers• Liquid to to Liquid• Air to to AirHAST Temperature‐Humidity ChambersHigh Altitude Simulation Chamber• Pressure, Humidity, and Temp. CyclingHigh Temperature Aging ChambersMixed Flowing Gas (MFG) ChamberElectrodynamic Vibration ChamberImpact and Drop Test ApparatusSIR TestingHollow Fiber AssessmentAcoustic Anechoic ChamberSample PreparationDiamond SawPolishing and Grinding StationPlasma EtchingUltrasonic CleaningWire BonderDie BonderBuehler MPC 2000 Cross‐sectioning SystemMaterials CharacterizationDifferential Scanning Calorimeter (DSC)Micro‐Mechanical Materials TesterThermo‐Mechanical Analyzer (TMA)Dynamic Mechanical Analyzer (DMA)Creep Testing EquipmentThin Film Analyzer (TFA)MTS servo‐hydraulic mechanical test system(5 (5 grams to to 200 kg)• High‐strain rate characterization (100/sec)• Tests can be conducted in in vacuum, inert or orreactive atmospheres (‐125 o C to to 300 o C) C)Micro‐Hardness TesterMicro‐Fatigue TesterAdhesion Tester1D Electrodynamic Shaker6D Electrodynamic ShakerDrop TowersTorsion TesterNon‐Destructive Evaluation3D X‐ray Imaging SystemScanning Acoustic Microscope (SAM)Fourier Transform Infrared Spectroscopy (FTIR)Automated Contact Resistance Probe (ACRP)X‐Ray Fluorescence Spectroscopy (XRF)Failure AnalysisEnvironmental Scanning Electron Microscope (ESEM)• (25x‐2500000x)• Energy Dispersive Spectroscopy (EDS)• In‐situ Heating/Mechanical TestingFocused Ion Beam (FIB)Stereoscopes (10x‐63x)Optical Microscopes (25x‐1000x, Inverted and Upright)Image Analysis SoftwareTransmission Electron Microscope (TEM)Wire Pull, Bond Shear, Cold Bump Pull and Die StrengthAutomatic Chemical DecapsulatorIon ChromatographOpto‐Mechanics ExperimentationGeometric MoireMicroscopic and Shadow Moire InterferometryInfrared Fizeau InterferometryTwyman‐Green InterferometryLuminous Flux Measurement System• 40” Integrating Sphere• SpectroradiometerVirtual Qualification LabcalcePWA Accelerated Test WebbookCADMP‐II PWA Assembly WebbookcalceFAST Integral Passives WebbookDefectsPWA Failure Mechanism WebbookWebbook Sensor Technology WebbookPEMs WebbookElectronic Testing and AnalysisSemiconductor Parameter AnalyzerImpedance Analyzer (1.86GHz)Microcircuit ProbeHigh Power Curve TracerLCR meterDynamic Signal AnalyzerEvent DetectorsElectrometerLCZ MeterThermal Inducing System (‐80 o C to to 225 o C) C)Time Domain ReflectometerAnalog OscilloscopesPower SuppliesHigh Speed Digital Oscilloscope up to to 20 GS/secDigital Communication AnalyzerArbitrary Wave Form GeneratorFunction GeneratorContact Resistance TesterNoise Figure AnalyzerVector Network AnalyzerHigh Resistance MeterDigital MultimetersAutomated Data Acquisition SystemsCascade Probe Station with RF probing capabilityAutomatic Battery Testers (Four and Sixteen ChannelSystems)Ripple Current TesterThermal Assessment and ManagementLiquid Crystal ThermographyLow Speed Wind TunnelHot Wire AnemometerFlow Visualization SystemHigh Speed Video CameraThermal Conductivity Testing SystemLaser Flash Thermal Property Measurement SystemFlow/Velocity Measurement FacilitiesPressure Measurement Facilitieswww.calce.umd.eduCenter for Advanced Life Cycle Engineering68bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013Center for Advanced Life Cycle Engineering69bpsood@calce.umd.edu301-405-3498University of MarylandCopyright © 2013