功率框架鋁絲鍵合失效與AOI檢查.pdf

1、華中科技大學(xué)碩士學(xué)位論文功率框架鋁絲鍵合失效與AOI檢查姓名：劉斌申請學(xué)位級別：碩士專業(yè)：納米科學(xué)與技術(shù)指導(dǎo)教師：吳懿平20110114II華中科技大學(xué)碩士學(xué)位論文ABSTRACTThebondliftheelcrackfailureofAlwirebondwithNicladofpowerdeviceleadframewasstudiedtheinterfacefractureoffailuresamplewasanalyzedwit

2、hmicroscopescanningelectronmicroscopy.Thefiniteelementanalysismodelofwirebondingprocesswasbuiltbysimplifyingthebondtoolmaterialloadingprocessonthebasisofrealbondingprocess.Thenthebondingprocesswassimulatedbyimptingthemod

3、eltoANSYSLSDYNA.Itwasfoundthatenoughdefmationofthebondmaterial(AlwireNiclad)wastherequirementofthebonding.WhenthewirewasbondedbylowparametersthedefmationoftheNicladAlwirewouldbetoosmalltofmabondwithhighstrengthnmalsizeth

4、erewouldbelargedisbondareainthecenterofthebondpointsothebondliftwouldeasilyariseduringthereliabilitytest.ButwhenthebondparameterwastoohightheexcessivedefmationoftheAlwirewouldleadtolargesizeofthebondpointthedeteriationof

5、theheelstrengthwhichcausedbytheextrusionfrictionofthebondingtool.thebondwouldbesubjecttoheelcrackduringthetemperaturecycletest.Theprocesswindowoftheactualproductionwastoonarrowtocontrolthebondquality.Toimprovethebondabil

6、ityreliabilityofthebondthemethodofreducingtheNicladhardnesswasproposed.Simulationexperimentshowedthatitcanexptheprocesswindowreducethebadbondpoint.Accdingtotheresultsoffailureanalysissimulationtestsimproperparameterwould

7、reducethebondqualityreliabilitywhichalsoleadtoabnmaldefmationofthebondmaterial.AlwiresecondbondontheNicladwasbondedwithdifferentparametersafterthevisualexaminationpeelingtestbondpulltestbondsheartestitwasfoundthattransve

8、rsedefmationofthebondwassensitivetothevariationofthebondparametersitcanbeusedastheacteristicparameterofthevisualtest.Accdingtotheactualsituationtheautomaticvisualinspectionofthebondpointwasfeasibletomeetthequalifications