快恢復(fù)二極管恢復(fù)技術(shù)的發(fā)展

快恢復(fù)二極管恢復(fù)技術(shù)的發(fā)展

網(wǎng)絡(luò)藝術(shù)rewellingsofterfici人的國際習(xí)慣法..3srafterfici治理對gra都亞地區(qū)的治療菲涅耳1的“能量可追溯性”是一個(gè)緩慢的步驟。如果你用緩慢的步驟，你可以用緩慢的步驟跑。第二階段是循環(huán)階段，如果循環(huán)cirep0s要長，則循環(huán)cirep0s；如果二級區(qū)域是卡盤定位，則二級區(qū)域是卡盤定位。如果二級區(qū)域是卡盤定位，則三級區(qū)域是卡盤定位。緩慢記錄和可滲透性路面的特征是第一階段，而微十字是第二階段。這是緩慢記錄和可滲透性路面的特征。這一階段是緩慢記錄和第二階段。returnityofficienso—III.CARRIERLIFETIMECONTROLSince1966,goldwasfirstusedasasemiconductorrecombinationcenter,thecarrierlifetimecontroltechnologyhasmadegreatprogressandcansignificantlyreducediodes’reverserecoverytime.Anddiodes’reverserecoverytimereducesfrommicrosecondleveltonano-secondlevelandafterthatitiscalledfastrecoverydiode.Peoplefoundthatitcaneffectivelyreducethecarrierlifetimebyintroducingthegoldintosemiconductor.Therebythediodeturnofftimewouldbegreatlyreduced.Unfortunately,itbringsaboutlargeleakagecurrent,increasedvoltagedropandotherissues.In1975,platinumwasfirstusedastheactivesemiconductorrecombinationcenter.Duringthesameperiod,methodsforcontrollingthelifetimeofcarriersbyelectronirradiationtechnologywasreported.Gold’srecombinationcenterisEc-0.55eV,platinum’srecombinationcenterandtheelectronirradiation’sisEc-0.23eVandEc-0.40eV,respectively.TheirenergybandsinsiliconareshowninFigure2.AccordingtoB.J.Baliga,therecombinationcenterisclosertothecenterofbandgap,thereverserecoverytimeofthedeviceissmallerandtheleakagecurrentisbigger.Comparedwithgold-dopeddevices,theonedopedwithplatinumissomewhatworseonTrr-Voncharacteristics,butthehavesmallerleakagecurrentandbettertemperaturestability.Sincetheheavymetaldiffusionrequireshighertemperature,thatmustcompletebeforeelectrodemetallization,whiletheelectronemissionisnotrequired.Butthedefectscreatedbyelectronirradiationarenotstable,theywillbedetrapedathightemperaturesover200?C.Therefore,thelong-termstabilityoftheelectronirradiationdeviceisnotgoodenoughandheavymetaldopeddeviceshavelong-termstabilitybecauseoftheformingofstablerecombinationcenters.In1977,palladium’slevelsinsiliconwasfoundbyL.So.In1978,L.Sosuccessfullyusedpalladiumasarecombinationcenterbyusingpalladiumdiffusioninsilicon.AccordingtoL.So,palladium’sdonorlevelinsiliconisEV+0.33eV,whiletheacceptorlevelisEc-0.22eV.Itcanbeknownthatasaneffectiverecombinationcenterinsilicon,palladium’sacceptorlevelissubstantiallythesameastheplatinum’s.So,likedevicesdopedwithplatinum,theonesdopedwithpalladiumhavethesamesmallleakagecurrent.Inaddition,thesolubilityofpalladiuminthesiliconis20%～50%lowerthanplatinumorgoldatdifferenttemperatures.Comparedwiththeplatinumdopedorgold-dopeddevices,itispossibletocontrolthecarrierlifetimemorepreciselybypalladiumdiffusiontechnology,andtheprogresscanbecontrolledbetter.Bycontrollingdiffusion,thecarrierlifetimeofthedevicesdopedwithpalladiumcanbepreciselycontrolledcontrolbetween10nsto1ms.However,thepalladium-dopeddevicesalsohavetheirdrawbacksasplatinum-dopeddevicesdo.TheirTrr-Voncharacteristicisworsethangold-dopeddevices.However,thesemetaldopingmethodsorelectronicirradiationtechnologyareintroducedtointernalrecombinationcenterofthedevice.Althoughitcanreducediodes’reverserecoverytime,thesaturatedvoltagedropofthedevicebecomesverylarge.Trr-Voncharacteristicofdiodeisverypoor.HowtoreducerecoverytimeandimprovethecharacteristicsofTrrVonatthesametimebecomesasevereproblem.In1983,D.C.Sawkousedprotonirradiationtechnologytoinitiatethelocallifetimecontroltechnologyandsuccessfullysolvedthisproblem.Becauseonlylocalcarrierlifetimeisreduced,theFRDsaturationvoltagedoesn’tincreasemuch.What’smore,itisabletogreatlyenhancetheperformanceofreverserecovery.Sothelocallifetimecontroltechnologyhasbeenrapidlydeveloped.Figure3showsatypicalionirradiationdiode’sdeepleveltransientspectroscopy(DLTSspectra).Table1showsthealphaparticledeeplevelsinsilicon.Asfortheexistingtechnology,theenergyofionirradiationcanreach30MeV.Andbycontrollingtheirradiationenergyofthedevice,itcanreachthedesiredaxialposition.Butitispropertoselectalowirradiationdoseinordertoavoidunneccessaryincreaseofleakagecurrentandthedecreaseofbreakdownvoltage.ThestudyofP.Hazdrashowsthatthebestportionofthelowlifetimeregionistheoneclosetotheanode.Atthistime,themaximumleakagecurrentofthedeviceislargeandthebreakdownvoltageisalsoeffected.Butbyoptimizingandcontrollingtheionirradiationdose,energyandotherparametersofthedevice,thesoftness,therecoverytime,thereverserecoverychargeandotherparameterscanbegreatlyimproved.However,whenthelowlifetimeregionisinsidetheanodeorinthebaseregionnearthecathode,theleakagecurrentissmall,andthereverserecoverycharacteristicofthedevicedoesnotperformwell.Inaddition,reducingofblockingvoltageofthedeviceisalsoadrawbackoflocalcarrierlifetimecontroltechnology.Inthepracticalprocess,apartfromthelocalcarrierlifetimecontrolbyionirradiationaddition,wegenerallycombinelocallifetimecontrolwithelectronirradiationtechnology,whichmainlysuppressesdynamicavalancheeffectofthedevice.Figure4isthedefectformedinthedifferentwaysinthedevice.Locallifetimecontroltechnologyhasunparalleledadvantages,suchasexcellentTrr-Voncharacteristics.Becausetherecombinationcenterisnearthecenterofthebandgap,alargeleakagecurrentisexpected.However,thedeviceswithplatinumorpalladiumdiffusionhavesmallleakagecurrent,buttheirTrr-Voncharacteristicsarepoor.Thus,peoplebegantoconsiderthecombinationofthesetwowaystoobtainbet-terperformanceofthedevices.Finally,in2005,J.Vobeckyproposedtheconceptofradiationenhanceddiffusion(RED).LocalvacancydefectsinducedbyhighconcentrationofionirradiationwillabsorbtheplatinumatomsinthePtSiwhichisprefabricated.Thisinducedthedefectformationwhichissimilartothelocaldistributionofplatinum.Itwasthefirsttimetoachievealocalplatinumdiffusiontechnologyinfastrecoverydiode.Comparedwiththetraditionallocallifetimecontroltechnology,thisnewtechniquehassmallerleakagecurrentundertheconditionofsamesaturationvoltageandpreventsdynamicavalanche.Inaddition,comparedwiththetraditionalalphaparticleirradiation,thisnewtechnologycan’treducethecarrierlifetimeinalargedegree,butthisnovelideabroughtgavecleardirectiontoimprovetheperformanceofFRD.PalladiumEnhancedDiffusiontheorycannotonlyreducethecarrierlifetimeoffastrecoverydiode,butalsoincreasethebreakdownvoltageandreducesthedynamicavalanchethroughthecompensationeffectforn-baseregion.Althoughthebandgaplevelofplatinumandpalladiuminsilicondevicesarealmostthesame,theperformanceofthepalladiumenhanceddiffusiondiodeisfarbetterthanthatoftheplatinum-enhanceddiffusiondiode.Whenthetemperaturerangesfrom500?Cto800?C,thepalladiumenhanceddiffusiondevices,incomparisonwithplatinum,notonlyimprovethebreakdownvoltage,butalsodelaythedynamicavalanche.However,platinumenhanceddiffusiondevicescannotshowsuchagoodperformance,whichreducethelifetimeofcarrierbysmallerextent,thegreatermaximumreverserecoverycurrent,andthenarrowersafeoperatingarea.Itisfoundthatinthetemperaturerangingfrom500?Cto650?C,theaccumulationinpeakareaoftheplatinumdefectisverydifferentfrompalladium.Onlyinaverynarrowtemperaturerange(700?Cto725?C)willplatinumhasanapparentbulkprocess,andn-basecompensationeffectappearinginthepalladiumenhanceddiffusionalsodisappearsinplatinumenhanceddiffusion.Bycomparisonofthetwomethods,platinumarenotsuitabletobeusedinenhanceddiffusion,evenifthistechniqueisfirstusedintheenhanceddiffusioninlowtemperatures.TableIIshowstheadvantagesanddisadvantagesofdifferentmethodswhichimprovetherecoveryCharacteristicoffastrecoverydiode.Wecanseefromthistablethatasthetimegoeson,thefastrecoverydiodedemonstratesbettercharacteristics.ThecharacteristicsofFRDareenhancedwiththehelpofcarrierlifetimecontroltechnology.IV.ANODEEMISSIONCONTROLTECHNOLOGYInadditiontothecarrierlifetimecontroltechnol-ogy,whichhasbeenprovedtogreatlyimprovetheperformanceofFRD,theanodeemissioncontroltechnologyisalsoprovedtobeoneoftheeffectivetechniquethatcanimprovetheperformanceofFRD.Holesemittedfromtheanodeintothebaseleadtoconductivitymodulation,thusreducingthevoltagedrop.However,theexcessholesinthebaseneedmuchtimetodrainoff,whichwouldincreasethedeviceturn-offlosses.Conductionvoltagedropandturn-offtimearecontradictory.Atlast,thekeypointofthedesigningoffastrecoverydiodeisindicatedastobalancebetweenthelowvoltagedropandshortturn-offtime.schott東南角公開價(jià)值的合成Schottkydiodeshaveashortrecoverytime,butthebreakdownvoltageisverylow.WhilethetraditionalPINdiode’breakdownvoltageishigh,therecoverytimeisverylong.Therefore,theintegrationoftheSchottkybarrierandPINbarrierdiodestructurewasbroughtup.However,thesestructureswereonlybroughtuptoimprovethebreakdownvoltageoftheSchottkyrectifier.In1987,B.J.BaligafirststudiedthereverserecoverycharacteristicsofdiodewithfusionofSchottkyandpnjunction,MPSdiodevoltagevalueshavebeenabletoreach400V.Figure6isastructurediagramofMPSdiode.Inthisnewstructure,PINstructureisusedtolaunchholesintothebaseregion,therebyreducingtheconductionvoltagedrop.TheforwardcurrentcrossestheSchottkysurfacesforthefirsttimebecauseofalowerSchottkybarriercontact(0.2V～0.4V).ThebreakdownvoltagecanbemaintainedatahighlevelbecausetheSchottkyjunctionisobscuredbytheelectricfieldandthepnjunctionistheparttosustainreverseblockingvoltage.ComparedwithconventionalPINdiode,MPSdiodecharacteristicshowsabetterbalanceofconductionvoltagedropandturn-offtime.Inthecaseofthesamevoltagedrop,MPSdiodehasafasterturn-offspeed.Furtherstudyshowed,itwasfoundthatthebreakdownvoltagecanrangefrom600Vto1200Vandthen4KV.MPSdiodeshowsabetterturn-offcharacteristicthantraditionalPINdiode.InordertovalidateMPSdiodecharacteristics,weuseATLASfromSILVACOtoasimulation.MPSdiodestructureparametersareshowninFigure6.Diodeturn-offconditionsareset:20?C,reverseblockingvoltageVr=800V,di/dt=4000A/us,currentdensity100A/cm2.Theturn-offcircuitofdiodeisshowninfigure7.Figure8showstheforwardconductioncharacteristicsoftraditionalPINdiode,MPSDiodeandpowerSBD.BecauseofthelowerSchottkybarrier,theMPSdiodehaslowervoltagedropthanPINdiodeatlowerforwardcurrentdensity.Asthecurrentdensityrises,theMPSdiode’sforwardvoltagedrophassmallerincreasethanthetraditionalPINdiode.AndthepowerSBDhasmuchhigherforwardvoltagedropthanMPSdiodeandPINdiode.Figure9isthecurrentdensityofMPSdiodeduringforwardconduction(100A/cm2).ForwardcurrentisflowingthroughtheSchottkysurfacebecauseofthelowerbarrierofSchottkycontact.Figure10isaMPSdiodeandatraditionalPINdiodeVon-Trrdiagram.Theyhavethesameturn-offconditions.Excepttheanoderegion,otherparametersareidentical.Ascanbeseenfromthefigure,MPSdiodehasabetterbalanceVdrop-TrrcharacteristicscomparedtoconventionalPINdiode.AndMPSdiodehasashorterrevoerytimewhenthevoltagedropissame.Orwhenthereverserecoverytimeisthesame,MPSdiodehasasmallervoltagedrop,andthedevicehaslesspowerloss.TheMPSdiodehasbetterrecoverycharacteristics.indexq基層黨組織stindwh4.Staticshieldingdiode(SSD)wasfirstintroducedbyY.Shimizuin1984.Thiskindofdiodehasalsobeengreatlydevelopedbecauseofitsgoodrecoverycharacteristics.Figure11isaconfigurationdiagramoftheSSDdiode.Asshowninthefigures,theshallowlightlydopedp-layerandaportionofthen-layeraresurroundedbythehighlydopedp+-layer.Thewidthofthepnjunctionsurroundedbythep+-layerisdefinedasthechannelwidthWch.Itwasfoundthatthemaincurrentcrossedthechannelwhenthediodeisforwardconducted.Inthereverseblocking,pnjunctionelectricfieldwillbeweakenedbyreducingthechannelwidth,therebyobtainingahigherblockingvoltage.Whenappliedtoreversevoltage,thepnjunctionisobscuredbytheelectricfieldofp+njunction.SothiskindofstructureisalsocalledStaticshieldingdiode(SSD).Figure12istheelectricfielddistributionwhenthediodeisinthereverseblockingstate.Itcanclearlydemonstratethiskindofelectricalfieldshieldingeffect.Atthattime,forwardvoltagedropof0.8Vandthereverserecoverytimeof87nsSSDdiodehadbeensuccessfullyfabricated.Althoughtheblockingvoltageisonly180V,theSSDdiodestillshowesaveryexcellentcharacteristic.In1991,600VSSDwasmanufacturedanditsIrrmreduced40%,Qrrlowered1/3,theturn-offspeedincreased1.5times.rewellingoffigulationmo對于rewellblot.和..和...和................3.4與rewell于veges....................................In1989,H.Schlangenottoproposedaself-regulatingemissionefficiencydiodestructure(SPEED).Figure13istheconfigurationdiagramofSPEEDdiode.Itsmostimportantfeatureisthattheanodeisinterposedbyhighconcentrationregionandlowconcentrationregion.Thisspecialstructuremakesp+regionemissionmoreefficientonlyathighcurrentdensity.Undernormalconditions,pemitterwillbeinefficientandsuchamechanismcandrasticallyreducethepeakreversecurrent.Whenreversebiased,thecarriersinthep+regionarerapidlypulledout,andthelargenumberofcarriersinthepregiondisappearinthemeanofrecombination,therebyincreasingthesoftnessofthedevice.Atthesametime,itissuitabletobeappliedinhighvoltageareasbecauseitisblockedmainlyinthepnjunctionareas.Figure14isthereverserecoverycurveofSSDdiode,SPEEDdiodeandtraditionalPINdiodeatthesamesaturationvoltage.Theyhavethesameturn-offconditions.Excepttheanoderegion,otherparametersareidentical.ItcanbeclearlyseenfromthefigurethatthereverserecoveryperformanceofSSDandtheSPEEDdiodePINdiodeshavebeengreatlyimprovedcomparedwiththeconventionalPINdiode.Amongthethreekindsofdiode,reverserecoverycharacteristicofSSDdiodeisthebest.Atthesamesaturationvoltage,thereverserecoverymaximumcurrentIrrmofSSDdiodeandSPEEDdiodeareincreasedby23%and16%respectivelycomparedwiththetraditionalPINdiode.Andtherecoverytimeisreducedbynearly12%.國際專利產(chǎn)品,即聯(lián)合網(wǎng)絡(luò)/indicteactindex和whichTwomainstreamtechnologieshavebeenusedtoimprovetheperformanceoffastrecoverydiode.Althoughthecarrierlifetimecontroltechnologyhasbeenproventobemoreefficientinthediodereverserecoverycharacteristicsthantheanodeemissionefficiencycontroltechnology,bothtechniqueshavebeendevelopedrapidly.Andinthepracticalprocess,engineersarewillingtousebothtechniquesatthesametimetoobtainbetterperformanceoffastrecoverydiodes,whichisalsothetrendofthedesignoffastrecoverydiodeinthefuture.Engineersarelookingfornewanodestructuretooptimizetheperformanceoffastrecoverydiodes.Atthesametime,theyarealsolookingfornewmethodtoreducethecostofcarrierlifetimekilling.Sothecostoffastrecoverydiodewhichhasbetterperformancewillbereducedinthefuture.What’smore,widebandgapsemiconductordevices,whicharerepresentedbythematerialsoftheSiCandGaN,indicatethefuturedirectionofthefastrecoverydiode.lopmeningofficiency,iq安全書,kh-pch-me行業(yè),u2004,3.,etsFastrecoverydiodesplayaveryimportantroleintheinvertercircuitsandtherectifiercircuits.WiththerapiddevelopmentoftheperformanceintheswitchingdevicesuchasIGBTandMOSFET,theperformanceofthefastrecoverydiodehasalsobeenconsiderablydeveloped.Inthispaper,carrierlifetimekillingandtheemitterefficiencycontrol,asthemostimportanttechniqueswhichimprovereverserecoverycharacteristicsoffastrecoverydiode,arereviewedindetail.關(guān)于“清”面向“認(rèn)同工具”的程序設(shè)置intraceinficieningPowerdiodesarewidelyusedinpowerelectronicsystemsaspopularswitchingdevices.IGBTandMOSFETmodulesarerequiredtohavebothlowlossswitchingandelectricalnoisesuppressingproperties.Inordertoattaintheseproperties,freewheelingdiodesinIGBTandMOSFETmodulesarebecomingextremelyimportantcomponents,forwhichlowlossandfastandsoftrecoverycharacteristicsareindispensable.Fastrecoverydiodeshavebeendevelopedinordertoachieveawidersafeoperatingarea(SOA),higherbreakdownvoltage,lowerleakagecurrent,fasterrecoverytimeandsofterrecoverycharacteristics.SomepaperspointoutthattheexcesscarrierdistributioninthebaseregionplaysanimportantroleintheFRDreverserecoverycharacteristics.Nowtherearetwomainmethodstocontrolthedistributionofexcessminoritycarriers,oneiscarrierlifetimekilling,theotherisemitterefficiencycontrol.Recombinationcentersinsidethesemiconductordevicescaneffectivelyreducethecarrierlifetimeandtheturn-offtime.Carrierlifetimekillingincludestheheavymetaldiffusion(gold,platinumandpalladium),electronirradiationandlocallifetimecontrolsuchasprotonirradiationandalphaparticleirradiation.EmitterefficiencycontroltechnologymainlyreducestheinjectionefficiencyfromtheanodetothedriftregioninordertoreducetheturnofftimeofFRD.Bothtechniques,whicharewidelyused,havebeenprovedtobeveryeffectiveincontrollingexcesscarrierstoimprovetheperformanceofFRD.Thisarticlewillmakeadetailedintroductionofthesetwomethods.Almostatthesametime,J.Vobeckysubstitutedplatinumwithpalladium,andwasthefirsttoachievepalladiumdiffusionlifetimecontrolbyirradiatingthelocalizeddefectatalowtemperatureannealingcondition(600?C～7