New Physical Model for Lifetime Estimation of Power Modules

[i=s]本帖最后由xujia023于2014-7-1810:41编辑[/i]

Abstract–Inthispaperaphysicalmodelforlifetime
estimationofstandardpowermodulesisproposed.The
lifetimepredictionisbasedontheassumptionthatthe
solderinterconnectionsaretheweakestpartofthemodule
assemblyandthatthefailurecauseistheinelastic
deformationenergyaccumulatedwithinthesoldermaterial.
Unlikethewell-knownCoffin-Mansonmodel,theproposed
modelcanbeusedtophysicallyexplainthedependencyof
lifetimeonthevariouspropertiesofatemperatureprofile
i.e.frequency,dwell-ramptime,minimum/maximum
temperature.ThemodelisbasedonClech’salgorithmfor
simulationofstress-strainsolderresponseundercyclical
thermalloadingandonthesolderdeformationmechanism
mapusedtodefinethedominantfailuremechanismunder
observedstress-temperatureconditions.Eitheraccelerated
cyclingtestsorexistingfielddatabasesareneededto
parameterizethemodel.Toverifytheapproach,theresults
ofpowercyclingtestsforahighpowerIGBTmodulefound
inliteratureareappliedandtheimpactsoftwomission
profilesonthemodulelifetimeareexamined.