芯片器件简介

芯片元器件（device）Snapshot2010-07-23魏文Confidential&Proprietary©20092Si&SemiconductorPNjunctionMOSintroduceMOSDevice特性.MOS2ndordereffect(advancedcharacter)AgendaConfidential&Proprietary©20093元素周期表P型掺杂N型掺杂Substrate衬底Confidential&Proprietary©20094+14n=1n=2n=3孤立硅原子2个电子8个电子4个电子s层有2个量子态p层有6个量子态1s22s22p63s23p2Confidential&Proprietary©20095硅原子组成晶体Confidential&Proprietary©20096N型-P型掺杂及其能带示意图N型掺杂P型掺杂Confidential&Proprietary©20097PNjunction（depletionlayerformation）1.Definition:nofreecarrier2.Wd:Na/Nd3.Bais:ForwarddecreaseWdConfidential&Proprietary©20098TheConductivityofPNJunctionERIThecurrentisformedbythemovementofthemajoritycarriers.Twotypesofmovements:majoritycarriers-diffusemovement(扩散运动).minoritycarriers–driftmovement（漂移运动).N型掺杂P型掺杂Confidential&Proprietary©20099TheConductivityofPNJunction正偏导通电压反偏击穿电压反偏ReverseBreakdown反向击穿pnjunctioncharacteristiccurve(伏安特性曲线)ThemostimportantcharacteristicofPNjunctionisthatitallowscurrentinonlyonedirection.PN结的最重要特性是它的单向导电性。Confidential&Proprietary©200910What’sMOSMetalOxideSemi..Confidential&Proprietary©200911MOSskeletonpn+n+VB,gndLVSVGVD•Whycalledsource/drain?•Canyoufigureoutwhichsideissource/draininpreviousslice?•Alwaysremember,MOSisfourterminal(includingBulk).Confidential&Proprietary©200912NMostransistor_Channelformationa.NoChannel,Ids=0b.Channelform,IdsflowfromDtoSc.IdsincreasewithVds,similartolinearResistord.Channelpinchoff.IdsindependentofVdsandsimilartocurrentsourceConfidential&Proprietary©200913•AsVDSisincreased:•AsVGS-VDSVt@thedrainendPinch-Off;•Atthismoment,VDS=VDS,satsaturationvoltage=VGS-Vt•IfVDSVDS,satoperationin“saturationregion”;•IfVDSVDS,satoperationin“trioderegion”NMoshowtowork(backup)Confidential&Proprietary©200914Transfer/Output•InthelinearregiontheMOSFETbehavesasaresistorcontrolledbyVG.•Insaturation,itbehavesasacurrentgeneratorcontrolledbyVG.IfVGSisVDsat(VGS),thebehaviorislinearwithslopeβ.VGS(V)ID(uA)weakinversionstronginversionlinearregionsaturation00.511.522.5VDS=0.1V151050VD(V)ID(uA)nonsaturationsaturation00.511.522.5VGS=4VVGS=5VVGS=3Vlinearregion(VDsat,IDsat)4003002001000Confidential&Proprietary©200915WATtestkeystructureandtestmethod_VtTestcondition:VTI_N18:VD=0.05V,VS=VB=0V,VG=0VTO0.8*1.8VMEASUREVTI_N18=VG@ID=0.1µA*(W/L)Testresult:VG=0.445VAABDGSVTI_NAA18_10_D18Confidential&Proprietary©200916SCE(shortchanneleffect)What:ShortChannelEffect,VtdecreasealongwithchannelLength.Why:S/Dlateraldiffuse(0.7Xj)anddepletionextensionintochannelcauseLeffreduce.How:Tox↓;Nb↑;Xj↓;Vsb↓Confidential&Proprietary©200917PT(Punchthrough)Confidential&Proprietary©200918JunctionBreakdownConfidential&Proprietary©200919BodyeffectWhat:VtincreasewithVsouce-VbulkWhy:VsbincreasetheS/Ddepletionlayer,whichattractmoreelectronsandcausechannelinversionlayerelectronloss,requestmoreGateeffect.How:Tox↓;Nb↓;Confidential&Proprietary©200920What:GateInducedDrainLeakage,bigleakagecurrentindrainsideespecialwhenVgd0.Why:GatetoDrainoverlayareageneratehighfield,leadtoavalanchemultiplicationandBTBT.How:Vg↓;Na↓;Vd↓GIDLConfidential&Proprietary©200921LeakageI1:JunctionleakI2:sub-thresholdleakageI3:OXtunnelingcurrentI4:GateHotcarriesleakageI5:GIDLI6:PunchthroughConfidential&Proprietary©200922ThankYou!