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IGBT雖然份額較小,但發(fā)展快速,從IGBT耐壓范圍上看,電壓在600V-1200V之間的IGBT用量最大,目前在電磁爐、電源、變頻家電等產(chǎn)品中使用的IGBT耐壓一般都是600V和1200V。低于600V的IGBT產(chǎn)品主要使用在數(shù)碼相機(jī)閃光燈和汽車點(diǎn)火器上。電壓大于1200V的IGBT主要以1700VIGBT為主,該產(chǎn)品在高壓變頻器等工業(yè)產(chǎn)品上廣泛使用。IGBT的應(yīng)用9/17/2023IGBT雖然份額較小,但發(fā)展快速,從IGBT耐壓范圍上看IGBT的主要生產(chǎn)廠商有:INFINEON,F(xiàn)AIRCHILD,IR,MITSUBISHI,ONSEMICONDUCTOR,F(xiàn)UJI,TOSHIBA,ABB,IXYS,ST等IGBT的主要生產(chǎn)廠商9/17/2023IGBT的主要生產(chǎn)廠商有:INFINEON,F(xiàn)AIRCH系列:2A-4000A;370V-6500V。1200A/3300V;400A/6500V(module);100A/1200V(singledie);5-25kHz,upto180kHzat370-600Vratings;IGBTcurrentandvoltageratings9/17/2023系列:2A-4000A;370V-6500V。IGBTc在高頻領(lǐng)域,2003年2月IR公司推出NPT(Non-Punch-Through)結(jié)構(gòu)的150KHz/600V系列IGBT;在高電壓應(yīng)用領(lǐng)域,Eupec生產(chǎn)的600A/6500V的IGBT模塊已獲得實(shí)際應(yīng)用;ABB公司采用軟穿通(Soft-Punch-Through)原則研制出8000伏IGBT。IGBTproducts9/17/2023在高頻領(lǐng)域,2003年2月IR公司推出NPT(NoPower(KVA)Applicationrangesofpowerswitchers9/17/2023Power(KVA)ApplicationrangesAdvantages:Insulatedgatecontrol(voltagecontrol)Lowforwardvoltagedrop(conductivitymodulation)Largeforward-biasedSOALargereverse-biasedSOAIGBTadvantages9/17/2023Advantages:IGBTadvantages8/4/Current(A)FIG-----IGBTofferreducedforwardvoltagedropcomparedtoaMOSFETwithsimilarrating.IGBTvsMOSFET9/17/2023Current(A)FIG-----IGBTofferIGBTStructureandOperationN-P+P+P+PPn+n+J1J2CollectorEmitterCGERSI9/17/2023IGBTStructureandOperationN-
IGBT的I-V特性VCEICEVGForwardCharacteristicsReverseCharacteristics9/17/2023IGBT的I-V特性VCEICEVGForwardRe
IGBT優(yōu)化的三角形原則9/17/2023IGBT優(yōu)化的三角形原則8/4/2023N-P+P+P+PPn+n+J1J2CollectorEmitterIGBTReverseBlockingCapability9/17/2023N-P+P+P+PPn+n+J1J2CollectorEmiJ1reversebiasedanditsdepletionlayerextendsprimarilyintothelightlydopedN-driftregion;2.Open-basePNPtransistorbreakdownlowreverseblockingcapabilityofthePT-IGBT;4.Junctionterminationproblem:ItisdifficultforplaneJTT.IGBTReverseBlockingCapability9/17/2023IGBTReverseBlockingCapabilIGBTForwardBlockingCapabilityn+n+p+p+ppp+n-CollectorEmitterJ1J29/17/2023IGBTForwardBlockingCapabilTheP-basedopingprofilelimiting;2.ThespacingbetweentheDMOScells;3.Open-basePNPtransistorbreakdown;4.JunctionterminationissimilartopowerMOSFETs;IGBTForwardBlockingCapability9/17/2023IGBTForwardBlockingCapabilSymmetricalDevicesN-P+P+P+PPn+n+J1J2CollectorEmitterDOPINGPN+NP+Dopingdistribution9/17/2023SymmetricalDevicesN-P+P+P+PPnSymmetricalDevicesDOPINGPN+NP+ElectricfieldFig.NPT-IGBTwithsymmetricblockingstructure.9/17/2023SymmetricalDevicesDOPINGPN+NPAsymmetricaldevicesN-P+P+P+PPn+n+J1J2CollectorEmitterPN+N-P+DOPINGNDopingdistribution9/17/2023AsymmetricaldevicesN-P+P+P+PPAsymmetricaldevicesPN+N-P+DOPINGNElectricfieldFig.PT-IGBTwithasymmetricblockingstructure.9/17/2023AsymmetricaldevicesPN+N-P+DOPOperationMechanismN-P+P+P+PPn+n+J1J2CollectorEmitterVG<VTOFFStateVG<VTandVCE>0ForwardBlockingStateVG>VTandVCE>0OnState9/17/2023OperationMechanismN-P+P+P+PPnForwardConductionStateN-P+P+P+PPn+n+J1J2CollectorEmitterCGIE9/17/2023ForwardConductionStateN-P+P+ForwardConductionStateN-P+P+P+PPn+n+J1J2CollectorEmitterCGERSI9/17/2023ForwardConductionStateN-P+P+PiNRectifier/MOSFETModeln-basep+pbasen+p+Emitter/cathodeCollector/AnodeJ2J1PiNdiodeMOSFETGECWusedtounderstanddevicebehaviorinmanycase9/17/2023PiNRectifier/MOSFETModeln-bPiNRectifier/MOSFETModelInanalyzingtheforwardconductioncharacteristicsbyusingthePiNrectifier/MOSFETmodel,thedeviceistreatedascomposedoftwosections.AssumingasinglecurrentflowpathexistingthroughthePiNdiodeandMOSFETconnectedinseries.UsingtheanalysisoftheforwardconductioncharacteristicsofaPiNrectifier,thevoltagedropacrossthePiNrectifier(VF,PiN)isrelatedtoitsforwardconductioncurrentdensity(JF,PiN)by:9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModelWhereWisthethicknessofthen-baseintheIGBTstructure.Here,weassumesthatthecurrentdensityinthePiNdiodeisapproximatelyequaltothecollectorcurrentdensityduetothefactthatthecurrentspreadsfromthebottomofthedriftandisuniformlydistributedacrossthecross-sectionofthedevicecellovermostofthedistancebetweenthecollectorandP-baseregionofIGBTs.So,thevoltagedropacrossthePiNdiodeisgivenby:
9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModelSincethePiNrectifiercurrentflowsthroughtheMOSFETchannel,theMOSFETcurrentisgivenby:Where,Wcellisthewidthoftheunitcell.9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModelThevoltagedropacrosstheMOSFET(VF,MOS)isrelatedtothecurrentflowingthroughit(IMOS)andthegatebiasvoltage(VGS)bytherelationshipdiscussedinpowerMOSFETs:Intheforwardconductionmode,sufficientgatevoltageisappliedsuchthattheforwardvoltagedropacrossthedeviceislow.Underthesecondition,theMOSFETsectionoftheIGBTisoperatinginitslinearregionandtheMOSFETcurrentisgivenby:9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModelThevoltagedropacrosstheMOSFETsectionisthereforegivenby:9/17/2023PiNRectifier/MOSFETModelThePiNRectifier/MOSFETModelThus,thevoltagedropacrosstheIGBTisthesumofthevoltagedropacrosstheMOSFETandthePiNrectifier:9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModelVCEICEVGOn-statecharacteristicsoftheIGBTbasedonthePiNrectifier/MOSFETmode.9/17/2023PiNRectifier/MOSFETModelVCEIPiNRectifier/MOSFETModelUsingthePiNrectifier/MOSFETmodel,itisalsopossibletoderivetheIGBTcharacteristicsundercurrentsaturation.WhenthevoltagedropacrosstheMOSFETchannelclosestotheVGS-Vth,theIGBTcurrentbecomeslimitedbytheMOSFET.Thus,theIGBTcollectorcurrentwillsaturateatavaluegivenby:9/17/2023PiNRectifier/MOSFETModelPiNRectifier/MOSFETModel
VG
VF
CurrentsaturationcharacteristicsVF~;MajorShortcoming:ItomitstheholecurrentcomponentflowingintotheP-baseregion9/17/2023PiNRectifier/MOSFETModelVGBipolarTransistor/MOSFETModelGECIEIMOSIBJTICn-basep+pbasen+p+Emitter/cathodeCollector/AnodeJ2J1MOSFETElectronCurrentHoleCurrent9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModel9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelThePNPtransistormusthavealargebasewidthinordertosupporttheforwardvoltage.Therefore,itscurrentgain(
PNP)isprimarilydeterminedbythebasetransportfactor(T)givenby:whereWun-depletedistheundepletedbasewidthofthePNPtransistorandLaistheambipolardiffusionlength.9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelTheanalysisofthevoltagedropacrosstheIGBTcanbeobtainedbyusingthesamemannerasdescribedearlierforthePiNrectifier/MOSFETmodel.However,itshouldbenoticedthattheMOSFETchannelcurrentis(1-
PNP)ICinthismodelnotICusedinthePiNrectifier/MOSFETmodel.9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelBasedonthetheoryoftheMOSFETLinearRegion:9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelSaturationDrainCurrent:9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelFig.7-4-5OutputcharacteristicsoftheIGBTforanalysisofthesaturationfeature.PT-IGBTNPT-IGBTVCEICE9/17/2023BipolarTransistor/MOSFETModeBipolarTransistor/MOSFETModelForPT-IGBT9/17/2023BipolarTransistor/MOSFETModeOn-statecarrierdistributionn-basep+pbasen+p+EmitterCollectorPiNIGBTJ2J1WP(x)PolysilicongateregionPolysilicongatewindow9/17/2023On-statecarrierdistributionnOn-stateForwardVoltageVJFETleadstoalargeVFImprovingmethod:IncreasingthedopingintheJFETregionN-P+P+P+PPn+n+J1J2CollectorEmitter9/17/2023On-stateForwardVoltageVParasiticthyristorlatch-upN-P+P+P+PPn+n+J1J2CollectorEmitterCGERSI9/17/2023Parasiticthyristorlatch-upN-Parasiticthyristorlatch-upN-P+P+P+PPn+n+J1J2CollectorEmitterCGERSILatch-up9/17/2023Parasiticthyristorlatch-upN-Parasiticthyristorlatch-upLatch-upcondition:
npn+pnp=1;
Themethodsforsuppresstheturn-onoftheparasiticthyristor:ReducingthegainoftheNPNtransistor,ReducingthegainofthePNPtransistor;ReducingthegainsofbothNPNandPNPtransistors.9/17/2023Parasiticthyristorlatch-upLaReductiontheGainoftheP-N-PTransistorMethod:
ReducingthebasetransportfactorbyreducingtheminoritycarrierlifetimeintheN-driftregion
Decreasingtheinjectionefficiencyoftheemitter
decreasingtheconcentrationoftheemitterbufferlayerCollector-shortedstructureTransparentcollectorstructureSincetheon-statecurrentflowspartiallyviathePNPtransistor,areducinginitsgainproducesanincreaseintheon-statevoltagedrop.9/17/2023ReductiontheGainoftheP-N-ReductiontheGainoftheN-P-NTransistorN-driftP+N-driftP+DeepP+diffusionShallowP+regionbyionimplantation.9/17/2023ReductiontheGainoftheN-P-ReductiontheGainoftheN-P-NTransistorN-driftP+ShallowP+regionbyionimplantationundertheN+emitter.P+9/17/2023ReductiontheGainoftheN-P-ReductiontheGainoftheN-P-NTransistorN-driftP+N+N+PP+Aself-alignedlatch-up-freeIGBTwithsidewalldiffusedN+emitter9/17/2023ReductiontheGainoftheN-P-SwitchingCharacteristicsBecausetheIGBTisaMOS-gateddevice,theturn-onswitchingperformanceisdominatedbytheMOSstructureofthedevice.VGEICVCEIdealizedturn-onswitchingofIGBT9/17/2023SwitchingCharacteristicsTypicalCapacitancevs.Collector-to-EmitterVoltageGA2000SA60SmadebyIR.9/17/2023TypicalCapacitancevs.CollecGateChargeTransferCurve9/17/2023GateChargeTransferCurve8/4/TurnoffAnimportantcharacteristicoftheIGBTisitsgateturn-offcapability.SincethecurrentflowingthroughtheMOSchannelcontrolstheoutputcharacteristics,thecollectorcurrentflowcanbeinterruptedbyremovingthegatedrivevoltage.WhenthegatevoltagefallsbelowthethresholdvoltageoftheMOSgatestructure,thechannelinversionlayercannolongerexist.Atthispoint,theelectroncurrent(Ie)ceases.Ifthegateturn-offisperformedusingalowexternalresistanceinthegatedrivecircuitsoasabruptlyreducethegatevoltagetozero,thecollectorcurrentwilldropabruptlybecausethechannelcurrent(Ie)issuddenlydiscontinued.9/17/2023TurnoffAnimportantcharacterTurnoffEvenafterthisoccurs,thecollectorcurrentcontinuestoflowbecausetheholecurrent(Ih)doesnotceaseabruptly.ThehighconcentrationofminoritycarrierstoredintheN-driftregionduringtheon-statesupportstheholecurrentflow.Astheminoritycarrierdensitydecaysduetotherecombination,itleadstoagradualreductioninthecollectorcurrent.Thiscurrentflowissometimesreferredtoasacurrenttail.Duringinductiveswitching,holesareinjectedfromtheanodesideinordertokeepthecurrentconduction,resultingalongercurrenttail.9/17/2023TurnoffEvenafterthisoccursTurnoffVGttICICCurrenttailFig.TypicalidealcurrentwaveformoftheIGBTduringturn-off.9/17/2023TurnoffVGttICICCurrenttailFTurnoffVGttICIC9/17/2023TurnoffVGttICIC8/4/2023TurnoffJustaswithMOSFETs,anegativebiascanbeappliedtothegateofanIGBTtospeeduptheturn-off.Thisdoesnotmeanthattherecombinationofminoritycarriersinthewidebaseregionwillbeincreased,butithelpstospeeduptheturnoffoftheMOSFETportion,andthusturn-offthebaseoftheintegralPNPbipolartransistorquicker.Therapidturn-offwillcauseahighdv/dt.9/17/2023TurnoffJustaswithMOSF9/17/2023Method1:RGReduceEoff_Rg
Therapidturn-offwillcauseahighdv/dt.9/17/20238/4/2023Method1:RGReduceEofReduce_EoffVg9/17/2023Reduce_EoffVg8/4/2023Turn-offlossGateDriver0V----15V-15V----+15VTurn-offLoss(mJ/cm2)14.356.93Turn-offlossatdifferentgatedrivers9/17/2023Turn-offlossGateDriver0V--VFandEOFFTrade-offMethod1:NPT&PTFig.Trade-offrelationshipbetweenVFandtoffforthePTandoriginalNPTIGBT.NPTPTtoffBV=600VVF9/17/2023VFandEOFFTrade-offMethod1:1.PT-IGBTvsNPT-IGBTFig.Structuresof(a)PT-IGBTand(b)NPT-IGBT.9/17/20231.PT-IGBTvsNPT-IGBTFig.2.LifetimeControlling9/17/20232.LifetimeControlling8/4/20233.BufferOptimizing9/17/20233.BufferOptimizing8/4/20234.CollectorEngineeringoftheIGBTP+PN-P+PN-nTransparentcollectorP+N+N-P+N+N-nShortedcollector9/17/20234.CollectorEngineeringoftheIGBT的開關(guān)特性9/17/2023IGBT的開關(guān)特性8/4/2023Diode-Clampedinductiveload9/17/2023Diode-Clampedinductiveload8/TurnOnWaveform9/17/2023TurnOnWaveform8/4/2023Itisarealisticswitchingwaveformconsideringthecharacteristicsofdioderecoveryandstrayinductance(LS).First,wesettheconditiontobeintheconstantsteadystatecurrent,whichinitiallyflowsthroughtheinductiveloadandthenflowsthroughtheidealdiode(freewheelingdiode)connectedinparallelwiththeinductiveload.TurnOnWaveform9/17/2023ItisarealisticsItisthesectionwherevGErisestoVGE(th)whileiGchargestheparasiticinputcapacitanceCge,Cgc.ThevGEincreasepatternisshowntobelinear,butitisactuallyanexponentialcurvewithtimeconstantRG(Cge+Cgc).ThevCEismaintainedattheVCCvalue,andiCremainsatzero.mostoftheturn-ondelayfallsunderthissection.t0section9/17/2023ItisthesectionwhevGEcontinuestoincreaseexponentiallypastVGE(th)asitdoesint0section.AsvGEincreases,iCbeginstoincreasetoreachIOwhichisthefullloadcurrent.Inthet1andt2section,vCEappearstobeshavedoffthanVCC.ThisisduetothevoltageinducedtoLSinFig.16duringtheincreaseiniC,VLS=LS*diC/dt.t1section9/17/2023vGEcontinuestoincreaseexpothediodecurrentwhichbeginstodecreasefromt1sectiondoesnotimmediatelyfalltozero,butthereisareverserecoverycurrentwhereitflowsinthereversedirection.ThiscurrentisaddedtoiCcurrenttotakethesameshapeasiCinthet2andt3section.t2andt3section9/17/2023thediodecurrentwhicht2andt3sectionAtthistime,thediodevoltagerecoversandincreases,andvCEdecreases,andwhenvCEishigh,itdecreasesrapidlyasCgctakesasmallvalue.Int3section,CgcdischargesbyabsorbingthegatedrivecurrentandthedischargedcurrentfromCge.Attheendoft3section,reverserecoveryofthediodestops.9/17/2023t2andt3sectionAttht4sectionInthissection,iGcontinuestochargeCgc.vGEmaintainsVGE,Iovalue,andiCmaintainsaconstantfullloadcurrent(IO).Atthistime,vCEhasalreadyfallensignificantly,andwhenvCEislow,thevalueofCgcislarge.Slowchargingcausesavoltagetail.9/17/2023t4sectionInthissectiot5sectionInthissection,vGEincreasesexponentiallytoVGG+withatimeconstantRG(Cge+Cgc,miller).Atthispoint,Cgc,millerisCgcwhichincreasesinthelowvCEvalueduetotheMillereffect.Inthissection,vCEdecreasesslowlytocollector-to-emitteron-statevoltageandbecomesfullysaturated.9/17/2023t5sectionInthissect9/17/20238/4/2023t6sectionThisisthesectionthatincludesmostofthetd(off)(Turnoffdelaytime).vGEfallsfromtheinjectedVGG+toVGE,Io.Atthistime,thereisnochangeinthevaluesofvCEoriC.9/17/2023t6sectionThisisthet7sectionThisisthesectionwherevCE(collectorvoltage)increasesandtherateofincreasecanbecontrolledwithRG(gateresistance).9/17/2023t7sectionThisisthesectiont8sectionAswiththeturn-ontransientperiod,thereisover-voltageasVLS=LS*diC/dtthatisinducedtostrayinductancefromtheeffectofdiC/dtisaddedtoIGBTC-Eterminalsinsectionst7and8.TheMOSFETcurrentdisappearsatt8,whichisthefirstofthetwosectionswhereiCdecreases.9/17/2023t8sectionAswiththeturn-ont9sectionPNPtransistorcurrent,outoftheIGBTiC,disappearsinthissection,andthiscurrentiscommonlycalledthetailcurrent.Ittakesplaceduetotherecombinationoftheminoritycarrier(hole),whichhasbeeninjectedintotheN-driftregionduringtheon-state.Duetotheexistenceofthisregion,theIGBT’sswitchingcharacteristicsareinferiorascomparedwithapowerMOSFET9/17/2023t9sectionPNPtransistorcurreSWITCHINGTIME9/17/2023SWITCHINGTIME8/4/2023td(on)(Turn-OnDelayTime)Thetimeittakesforthecollectorcurrenttoreach10%ofIOfromthetimeapulseisinjectedintothegate.9/17/2023td(on)(Turn-OnDelayTime)TheTr(RiseTime)Thetimeittakesforthecollectorcurrenttoreach90%ofIOfrom10%.Anyfallinthecollectorcurrentafterthatpointisnotconsidered.9/17/2023Tr(RiseTime)Thetimeittaktd(off)(Turn-OffDelayTime)Thetimeittakesforthecollector-emittervoltagetoreach10%ofVCCfromthetimeapulseisremovedfromthegate(90%ofVGG+).9/17/2023td(off)(Turn-OffDelayTime)TTf(FallTime
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