ContentsIllustrationsandTablesxviiAbbreviationsxxiiiPrefacexxviChapter1.TheNatureofSixSigmaandItsConnectivity1toOtherQualityTools1.1HistoricalPerspective11.2WhySixSigma?41.3DefendingSixSigma71.4TheDefinitionsofSixSigma81.5IncreasingtheCpLeveltoReachSixSigma91.6DefinitionsofMajorQualityToolsandHow10TheyEffectSixSigma1.7MandatoryQualityTools101.8QualityFunctionDeployment(QFD)111.8.1Engineering111.8.2Management111.8.3Marketing121.9DesignforManufacture(DFM)001.10DesignofExperiments(DoE)001.11OtherQualityTools201.11.1Processmapping211.11.2Failuremodesandeffectsanalysis(FMEA)261.12GaugeRepeatabilityandReproducibility(GR&R)291.13Conclusions301.14ReferencesandBibliography31Chapter2.TheElementsofSixSigmaand33TheirDetermination2.1TheQualityMeasurementTechniques:SQC,SixSigma,CpandCpk342.1.1TheStatisticalqualitycontrol(SQC)methods342.1.2Therelationshipofcontrolchartsand35sixsigma2.1.3Theprocesscapabilityindex(Cp)362.1.4Sixsigmaapproach39viiCopyright2002TheMcGraw-HillCompanies,Inc.ClickHereforTermsofUse.Formoreinformationaboutthisbook,clickhere.2.1.5Sixsigmaandthe1.5shift412.2TheCpkApproachVersusSixSigma422.2.1Cpkandprocessaverageshift432.2.2NegativeCpk442.2.3ChoosingsixsigmaorCpk452.2.4Settingtheprocesscapabilityindex462.3CalculatingDefectsUsingNormalDistribution472.3.1RelationshipbetweenzandCpk542.3.2ExampledefectcalculationsandCpk542.3.3Attributeprocessesandrejectanalysisfor57sixsigma2.4AreManufacturingProcessesandSupplyParts59AlwaysNormallyDistributed?2.4.1Quickvisualcheckfornormality592.4.2Checkingfornormalityusingchi-squaretests602.4.3Exampleof2goodnessoffittonormal62distributiontest2.4.4Transformationdataintonormaldistributions632.4.5Theuseofstatisticalsoftwarefor65normalityanalysis2.5Conclusions652.6ReferencesandBibliography66Chapter3.SixSigmaandtheManufacturingControlSystems693.1ManufacturingVariabilityMeasurementandControl703.2TheControlofVariableProcessesandIts72RelationshipwithSixSigma3.2.1.Variablecontrolchartlimits743.2.2Controlchartlimitscalculations743.2.3Controlandspecificationslimits753.2.4X,Rvariablecontrolchartcalculations76example3.2.5Alternatemethodsforcalculatingcontrol78limits3.2.6Controlchartguidelines,out-of-control78conditions,andcorrectiveactionproceduresandexamples3.2.7Examplesofvariablecontrolchart82calculationsandtheirrelationshiptosixsigma3.3AttributechartsandtheirRelationshipwith84SixSigmaviiiContents3.3.1Thebinomialdistribution853.3.2Examplesofusingthebinomialdistribution863.3.3ThePoissondistribution863.3.4ExamplesofusingthePoissondistribution873.3.5Attributecontrolchartslimitcalculations883.3.6Examplesofattributecontrolcharts89calculationsandtheirrelationshiptosixsigma3.3.7Useofcontrolchartsinfactoriesthatare91approachingsixsigma3.4UsingTQMTechniquestoMaintainSixSigma91QualityinManufacturing3.4.1TQMtoolsdefinitionsandexamples923.5Conclusions993.6ReferencesandBibliography99Chapter4.TheUseofSixSigmainDeterminingthe101ManufacturingYieldandTestStrategy4.1DeterminingUnitsofDefects1024.2DeterminingManufacturingYieldonaSingle104OperationoraPartwithMultipleSimilarOperations4.2.1Exampleofcalculatingyieldinapartwith105multipleoperations4.2.2DeterminingassemblyyieldandPCBand106producttestlevelsinelectronicproducts4.2.3PCByieldexample1074.3DeterminingDesignorManufacturingYieldon108MultiplePartswithMultipleManufacturingOperationsorDesignSpecifications4.3.1Determiningfirst-timeyieldattheelectronic110productturn-onlevel4.3.2ExampleofyieldcalculationsatthePCB110assemblylevel4.3.3DPMOmethodsforstandardizingdefect112measurements4.3.4DPMOcharts1134.3.5CritiqueofDMPOmethods1154.3.6TheuseofimpliedCpkinproductand116assemblylinemanufacturingandplanningactivities4.3.7ExampleanddiscussionofimpliedCpkin118ICassemblylinedefectprojections4.4DeterminingOverallProductTestingStrategy120Contentsix4.4.1PCBteststrategy1214.4.2PCBteststrategyexample1234.4.3In-circuittesteffectiveness1274.4.4Factorsaffectingtestoperationparameters1284.4.5Testcoverage1284.4.6Badandgoodtesteffectiveness1294.4.7Futuretrendsintesting1304.5Conclusions1304.6ReferencesandBibliography131Chapter5.TheUseofSixSigmaWithHigh-and133Low-VolumeProductsandProcesses5.1ProcessAverageandStandardDeviation134CalculationsforSamplesandPopulations5.1.1Examplesoftheuseofthet-distributionfor137sampleandpopulationaverages5.1.2Otherstatisticaltools:Pointandinterval138estimation5.1.3Examplesofpointestimationoftheaverage1395.1.4Confidenceintervalestimationfortheaverage1405.1.5Standarddeviationforsamplesand142populations5.1.6Examplesofpopulationvariance144determination5.2DeterminingProcessCapability1455.2.1Processcapabilityforlarge-volume146production5.2.2Determinationofstandarddeviationfor148processcapability5.2.3Exampleofmethodsofcalculating1495.2.4Processcapabilityforlow-volumeproduction1505.2.5Movingrange(MR)methodologiesforlow150volume:MRcontrolcharts5.2.6Processcapabilitystudiesinindustry1525.3DeterminingGaugeCapability1545.3.1GR&Rmethodology1565.3.2ExamplesofGR&Rcalculations1585.3.3GR&Rresultsinterpretation1595.3.4GR&Rexamples1605.4DeterminingShort-andLong-