用階梯狀摻雜埋層對(duì)超淺結(jié)進(jìn)行C-V剖面分析(英文).docxVIP

1、器件制造身成闈咐MnufacturingmdApplicationofDevicedoi：10.3969/j.issn.1003-353x.2010.01.009CVProfilingofUltrashallowJunctionsUsingaBuriedLayerwithStep-LikeDopingProfileXuCuiqin1,2,PopadicMilo§2,NanverL.K.2,RuGuoping1(1.StaleKeyl/ibofASICandSystems,DepartmentofMicroelectronics,FudanUniversity,Shanghai2004

2、33,China;2.laboratoryofECTM,DIMES,DelftUniversityofTechnology,CHDelft2600.Netherlands)Abstract：Two-sidedC-VtechniquewasinvestigatedforapplicationindopingprofilecharacterizationofSiultrashallowp*-njunctions.Expressionswerederivedfortheevaluationofthedopingprofileinthep*region,basedontheknowledgeofcap

3、acitance-voltage(C-Vr)relationshipofthep*-ndiode,thedopingprofileinnregion,andthedepletionwidthinnregionatthermalequilibrium(xM).SteppeddopingprofileinnregionwasdesignedforaccuratedeterminationofxM,acrucialparameterfortheextractionofthedopingprofileinthep*region.Medicisimulationswerecarriedoutforthe

4、C-VRrelationshipsofthep*-nandn-Schottkyjunctionswiththesamestep-likenprofile.ThedopingprofileinnregioncouldthenbeextractedfromtheC-VRrelationshipoftheSchottkydiode.Theisdeterminedwithanaccuracyof1.8nmbyacriteriondeveloped.Andthedelingprofileinthep*regioncanfinallybeextractedandshowntobeingoodagreeme

5、ntwiththeMedicisimulationresults.Keywords：two-sidedjunction;C-V;ultra-shallowjunctionsCLCnumber：TN301.07;TN3O5.3Documentcode：AArticleID：JOB-353X(2010)01-0039-01EEACC:253OB;255OB;7110用階梯狀摻雜埋層對(duì)超淺結(jié)進(jìn)行C，剖面分析徐翠芹PopadicMilo*,NanverL.K.2,茹國(guó)平】（1.復(fù)旦大學(xué)微電子系專用集成電路與系統(tǒng)國(guó)家重點(diǎn)實(shí)驗(yàn)室，上海200433；2.代爾夫特工業(yè)大學(xué)ECTM/DIMES實(shí)驗(yàn)室，荷蘭代爾夫

6、特2600）摘要：研究了應(yīng)用雙邊C-V法測(cè)量超淺結(jié)（如p*-n結(jié)）的疹雜分布。推導(dǎo)了在已知p-n結(jié)的電容-電壓（C-*）關(guān)系、n區(qū)摻雜、以及熱平衡下n區(qū)耗盡層寬度（xM）的情況下計(jì)算p區(qū)疹雜濃度分布的公式。與湖是計(jì)算p區(qū)摻雜分布所需的一個(gè)關(guān)鍵參數(shù)，通過(guò)將n區(qū)摻雜設(shè)計(jì)成階梯狀，可實(shí)現(xiàn)對(duì)*的精確提取。用Medici對(duì)具有相同的階梯狀摻雜n區(qū)的p'-n和n-肖特基結(jié)進(jìn)行器件仿真可得其C-Vn關(guān)系。運(yùn)用常規(guī)GU法，由肖特基結(jié)的C-Vn關(guān)系可提取出n區(qū)摻雜濃度。實(shí)現(xiàn)了對(duì)*3的精確提取，其精度達(dá)1.8nma基于精確的為洵，運(yùn)用雙邊C-V法提取的p*區(qū)的摻雜濃度分布與Medici仿真結(jié)果非常吻合。關(guān)

7、鍵詞：雙邊結(jié)；電容-電壓；超淺結(jié)中圖分類號(hào)：TN3W.07；TN3O5.3文獻(xiàn)標(biāo)識(shí)碼：A文章編號(hào)：1003-353X（2010）01-0039-040IntroductionUltrashallowsourceanddrain(S/D)junctionswithFoundationitem：Shanghai-AppliedMaterialsResearchDevelopmentFund(07SA06)highandabruptdopingprofilearenecessaryforgoodperformanceofMOSFETs'E.Itisveryimportantandchalle

8、ngingtomeasuretheactivateddopinglevelanditsdistributionthroughtheultrashallowjunctionsbecauseofthestringentdepthresolutionandquantitativeaccuracyrequirements.Atpresent,thereareseveralprofilingtechniques,suchassecondaryionmassspectrometry(SIMS),spreadingresistanceprofiling(SRP),differentialcapacitanc

9、e-voltage(C-V)profiling,electrochemicalcapacitance-voltage(ECV)profiling,profiling,Halleffectprofiling,andRutherfordbackscattering(RBS.Eachlechniquehasitsadvantagesanddisadvantages.Inthiswork,anoveltwo-sidedC-Vprofilingisdeveloped.ThedopingprofileononesidecanbeextractedbasedontheknowledgeoftheC-Vrel

10、ationship,thedopingprofileontheotherside,andtheboundaryofdepletionregionatthermalequilibrium(.Thetwo-sidedprofilingtechniquecanbesuccessfullyappliedfortheprofilingofp+regionofp*-njunctionwithasteppedndopingprofile.1 TheoryofTwo-SidedCVProfilingTechniqueThedopingprofileofanarbitrarydopedp-njunctionis

11、showninFig.1./Vd(x)andN.(x)representthedonorprofileinnregion(x<0)andacceptorproGleinpregion(x>0),respectively.W(VT)isthewidthofthedepletionregionwhenthetotalpotentialdropthroughthejunctionequalstoVytwhichisthesumofthebuild-involtage,andreversebiasVr.xnandxparethecoordinatesofthedepletionregion

12、edgesinthevicinityofneutralnandpregions,respectively.Fig.1DeGnitionsofanarbitrarydopedpnjunction圖1任意摻雜pn結(jié)的定義Assumingthatalldopantatomsareactive,withdepletionapproximation,theequationscanbeobtained一習(xí):electricallyfollowing收(4)%"=一L業(yè)與g1-秋(*)宓住QAtthermalequilibrium,equalsto*，andxnequalstoxM.FromEq.

13、(1),thefollowingequationcanbeobtainedWithacertainreversebiasvoltageapplied.Eq.(1) canbewrittenas；住山一滁+'齋(5)CombiningEqs.(4)and(5)yieldsQbi="eJo敗(Vr)=-:CUr)Mr(6)WhereAistheareaofthediode,tisthepermittivityofthesemiconductor,andCisthecapacitanceofthediode.Witharightassumptionofxoandtheknowled

14、geofthedopingprofileinnregion,usingEq.(6),xnti(Ur)whichstandsfortheestimatedrelationshipbetweenxnandVrcanbecalculated.ThenbasedonthemeasuredC-Vrrelationshipofp-njunction,W()canbecalculatedandtheestimatedxp-relationship,xpM(i(Yr)canbecalculatedusingEq.(2).Intheend,N.(xp)canbereconstructedfromEq.(3).2

15、 MediciSimulationofTwo-SideC-VProfilingInthetwo-sidedC-Vprofiling,isanimportantbutunknownparameter.What'smore,thedopingprofileinnregioncannotbetakenasknowndirectly.Inthiswork,itissuggestedthatifusingap*-njunctionwithastep-likenprofile,thevalueofcanbeevaluatedaccurately.Andthedopingprofileinnregi

16、oncanbemeasuredonn-Schottkydiodewiththesamenprofileasp*-njunction.MedicisimulationsareimplementedfortheC-VRrelationshipsofp*-nandSchottkydiodeswiththesamestep-likedopingprofileinnregion.Atthermalequilibrium,thesimulateddopingandcarrierprofilesofp*-njunctionwithstep-likenprofileareshowninFig.2.Theare

17、asofthep*-ndiodeandSchottkydiodearebothsetto1mx1pm.DCsolutionsofSchottkyandp*-ndiodearesolvedatdifferentreversebiases,0-25Vand015Vwithastepof0.1V,respectively.Duringthisprocess,Poisson*sequation,continuityequationsandthecarriertransportequationsareallcoupledandsolvedbyusingnumericalmethod.Mediciperf

18、ormsACanalysisasapost-processingstepaftereachDCsolution.ACsmallsignalsimulationsarecarriedoutateachDCbiasingbyapplyingasinufu)idalsignalutafrequencyof1MHzwithasmallamplitudeof10mV.ThesimulatedC-VKcharacteristicsofthep*-ndiodeandn-SchottkydiodewiththedopingprofilesareshownintheinsetofFig.2.Fig.2Simul

19、atedcarrieranddopantconcentrationprofilesofp*-njunctionatthermalequilibrium,theinsetshowsthesimulatedC-VHcharacteristicsofthep*-nandn-Schottkydiodes圖2仿真中的p-n結(jié)摻雜濃度分布以及熱平衡F的城流子濃度分布，插圖為仿真得到的p-n結(jié)和n肖特基結(jié)的C-*關(guān)系Takingtheestimatedelectronprofileofn-Schottkydiodeastheelectronprofileatthermalequilibriumofthep*

20、-ndiode,basedontheMedicisimulatedCVKrelationshipofp*-njunction,two-sidedprofilingtechniqueisimplementedwithdifferentassumptionofasiwinw.=-99-96nm).Withdifferent,Mumc,differentxpzi-VrrelationshipscanbecalculatedassliowninFig.3.Theoretically,thedepletionwidthinpregionshouldincreaseasthereversebiasincr

21、eases.However,-Kt/VFig.3Estimatedxp-VKrelationshipsfordifferentxM,uiwe圖3不同gi下所估算出的x-VH關(guān)索asshowninFig.3,withla建eraume,theestimatedxp-VKrelationshipsdecreaseatthefirstfewbiaspoints.Thisabnormalphenomenoncanbeexplainedasfollows.AsindicatedinFig.2,theestimatedelectronconcentrationdecreasesasxincreases.F

22、orthesameamountofelectronstobedepleted,ifx*8umrislargerthantherealvalueof為thestepofxn)willbelargerthantherealvalue.IfaMumcistoolarge,thestepofxnMti(Vr)maybeevenlargerthanthestepofW(Yr),whichinducesxpeslj(FR)todecreaseatthefirstfewbiaspointsuntilxnreachesthehighlydopedregion.Thisphenomenonisillustrat

23、edmoreclearlyinFig.4.With丸sazEeequals-96nm,forthefirstfewbiaspoints,thestepwidthofxn_cMi(Hr)islargerthanthatofW(Vr),sothestepofxp5(*)isnegative,andxpe8ti(Hr)woulddecreaseatthefirstfewbiaspoints.Afterafewbiassteps,theconcentrationdifferenceinducedbythelargerxMassumcwilldisappearandthestepofxpwli(VR)b

24、ecomepositiveandxpc#li(Vr)willincrease'*.ThisphenomenonoffersawaytodeterminetheupperlimitofInthiscase,thelimitisthattheassumedshouldbesmallerthan-97.2nmasindicatedinFig.3.If心.umeissmallerthantherealvalueof«thestepofxncgli(Vr)willbesmallerthantherealvalue,sothestepofxpMli()willalwaysbepositi

25、veandxpeMi(VR)willalwaysincreasewithVr.Thereforeitisdifficulttofigureoutthelowerlimitoffromthexprelationship.Ontheotherhand,thewrongaMMinw.willresultinnotonlywrong%pwlibutalsowrongNaIf*洵皿叩職issmallerthantherealvalueofxp_mi(Ur)seemsFig.4Withxz=-96.0nm,thestepsofdepletionwidth,theestimatedxn,andtheesti

26、matedxpasfunctionsofreversebias圖4七45=-96.0nm時(shí).耗盡層寬度、估算出的%、和與反偏電斥的關(guān)系normal,buttheestimatedp+dopingprofile,asshowninFig.5,isnotsmooth'】.ThisphenomenoncanbeusedasacriteriontodeterminethelowerlimitofwhichisspecifiedasxMmin.AsshowninHg.5,whendecreasesto-99nm,theeg|j-xbecomesnon-smooth,Fig.5Estimatedp

27、*dopingprofilewithxMaMluin<.=-98.0,99.0and-100.0nm圖5xs.ze為-98.0,-99.0,-100.0nm時(shí)所提取的P區(qū)摻雜濃度分布InFig.6istheacceporprofileestimatedwith=-98nm,andthesimulatedacceptorprofileandholeprofileatthermalequilibrium.Fig.5Estimatedp*dopingprofilewithxMaMluin<.=-98.0,99.0and-100.0nm圖5xs.ze為-98.0,-99.0,-100.0n

28、m時(shí)所提取的P區(qū)摻雜濃度分布InFig.6istheacceporprofileestimatedwith=-98nm,andthesimulatedacceptorprofileandholeprofileatthermalequilibrium.rm。/*,NAlthoughitisimpossibletohavetheexactvalueofrealinpractice,Netli(x)shouldbeveryclosetothetruevalueswhentheinterval(xMmin,)issmallenough,around1.8nminthiscase.Astheexperi

29、mentalapplicationofthetwo-sidedC-VproGlingtechniqueisconcerned,accuratemeasurementofjunctionareaisnecessary.Otherwise,thedopingprofileinnregionandconsequentlythedopingprofileinthep*regioncannotbesuccessfullyestimated.Fig.6Acceptorprofileestimatedwithx”=-98.0nm,aridthesimulatedacceptorprofileandholep

30、rofileatthermalequilibrium圖6xo=-98.0nm時(shí)所提取的受主摟雜濃度分布，及仿真所得到的熱平衡下的受主和空穴濃度分布Fig.6Acceptorprofileestimatedwithx”=-98.0nm,aridthesimulatedacceptorprofileandholeprofileatthermalequilibrium圖6xo=-98.0nm時(shí)所提取的受主摟雜濃度分布，及仿真所得到的熱平衡下的受主和空穴濃度分布?£>MWConclusionThenoveltwo-sidedC-VproGlingtechniqueisproposedt

31、hatthedopingprofileononesideofp-ndiodecanbecalculatedbasedontheknowledgeoftheC-*relationship,thedopingprofileontheotherside,andtheboundaryofdepletionregionatthermalequilibrium.Hietwo-sidedC-VprofilingtechniqueissuccessfullyappliedforSiultrashallowjunctions.Theteststructureofp*-nandn-Schottkydiodeswi

32、ththesamestep-likenprofileisdesignedforextractionofthedopingprofileinthep*regionusingthetwo-sidedprofilingtechnique.BasedontheMedicisimulationoftheC-relationshipsofultra-shallowp*-nandn-Schottky,ononehand,thedopingprofileonthensidecanbeextractedfromtheC-VRrelationshipofSchottkydiode.Ontheotherhand,w

33、ithdifferentaume»applyingthetwo-sidedC-Vprofilingtechnique,theupperandlowerlimitsofcanbedetermined,baseonthe氣。"*andVRrelationships,respectively.Theaccuracyofisshowntobeabout1.8nm.Itisdemonstratedthatifisassumedtobewithintheupperandlowerlimits,thedopingprofilesinthep*regioncanbeaccuratelyev

34、aluated.Thereforeitcanbeconcludedthatthenoveltwo-sidedC-Vprofilingtechniquemaybeappliedfortheextractionofthedopingprofileofultra-shallowjunctions.(下轉(zhuǎn)第89頁(yè))了大量的鍵合過(guò)程中換能桿末端軸向的速度信號(hào)。通過(guò)分析這些鍵合的強(qiáng)度得到了欠鍵合和過(guò)鍵合對(duì)應(yīng)的功率設(shè)置范圍。分析了超聲功率設(shè)置和鍵合溫度對(duì)換能桿振幅的影響規(guī)律，解釋了不同功率設(shè)置和溫度導(dǎo)致欠鍵合和過(guò)鍵合的可能原因，建立了功率設(shè)置和溫度對(duì)換能桿振幅影響的模型。參考文獻(xiàn)：】WANGFL,UJH,H

35、ANL,etal.EffectofultrasonicpoweronwedgebondingstrengthandinterfacemicrostructureJ.TransactionsofNonferrousMetalsSocietyofChina(EnglishEdition),2007,17(3)：606-611.2 SUCT,CHIANGTL.Optimaldesignforaballgridarraywirebondingprocessusinganeuro-geneticapproachj.IEEETransonElectronicsPackagingManufacturing,

36、2002,25(1)：13-18.3 IQNGZL,HANL,WUYX,etal.ExperimentstudyoftemperatureparametereffectonbondingprocessandqualityinthermosonicwirebondingC/Procof6,hIntConfonElectronicsPackagingTechnology.2005,Shenzhen,Guangdong,China,186-193.4 許文虎，韓缶.Hilbert變換在求取超聲換能系統(tǒng)速度導(dǎo)納中的應(yīng)用J.現(xiàn)代機(jī)械.2005,(6):6-15.5】幃雷，許文虎，李涵雄.超聲鍵合換能系統(tǒng)

37、非穩(wěn)態(tài)特性實(shí)(上接第42頁(yè))References:1 WONGHSP,FRANKDJ,SOLOMONPM,etal.NanoscaleCMOSJ.ProcIEEE,1999,87:537-570.2 MOOREGE.ProgressindigitalintegratedelectronicsC/7ProcofIEDM.Washington,USA,1975:11-13.3 KURATAH,SUGIIT.Impactofshallowsource/drainontheshort-channelcharacteristicsofpMOSFETsJ.IEEEEDL,1999,20(2):95-96.

38、4 JONESEC,ISHIDAE.ShallowjunctiondopingtechnologiesforULSIJ.MaterSciEng,1998,24：1-80.5 SCHRODERDK.SemiconductormaterialanddevicecharactenzationM.NewYork：JohnWileyandSons,1998：160-272.6 MANHJJD.OnthecalculationofdopingprofilefromC(V)measurementontwo-sidedjunctionsj.IEEETransonED,1970,17(12):1087-1088.7 Synopsysinc.Taurusmedici:m