MOS晶体管基本特性表征

上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation1ConfidentialMOSFETBasicCharacterization(MOS晶体管基本特性表征)WenyuGao2008/04/18上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation2Confidential1.MOSFET的特性曲线与特征参数2.短沟效应(SCE&RSCE)3.窄沟效应(NWE&RNWE)与STI寄生晶体管上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation3ConfidentialC-V特性曲线1.N-type,P-type;majority-carrier(多子),minority-carrier(少子).2.Accumulation(积累),depletion(耗尽),inversion(反型)。DBSGN+polyPWeeehhh-N+polyPWeeee+hN-N+polyPWeee+hhhNMOSFETNMOSCapacitorN+polyPWGBBGCpolyCoxCsiN+polySDEorLDDSpacerPWN+N+S/DN-N-gateoxide上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation4ConfidentialC-V特性曲线-cont11.Poly等效厚度与其掺杂浓度有关，一般10A；2.反型层等效厚度~8A；BGCpolyCoxCsiTeq=Tox+Tpoly+Tinv上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation5ConfidentialC-V特性曲线-cont21.栅介质厚度对积累区和反型区电容都有影响；2.氧化物电荷Qf会造成CV平移；3.Polydepletion仅对反型区电容有影响;4.Vg=+/-Vdd常作为WAT的监控点，测量等效电学厚度Teq和Tox。5VNMOSFETTCADdata上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation6ConfidentialI-V特性曲线•MOSFET最主要的特性曲线为Id-Vg,Id-Vd曲线.特别是Id-Vg;线性区(萨氏方程)：dsdsthgsoxsdsVVVVLWCI5.0RVIVVchdsdsgsth()1LWCoxsthgsVV饱和区：2)(2thgsdsatVVIthgsdsatdVVVVRon=Rch(Vgs=Vdd)0.00E+001.00E-052.00E-053.00E-054.00E-055.00E-0500.20.40.60.811.2Vg(V)Id(A)Vd=0.1V,Vb=0V,Vs=0VVd=1.2V,Vb=0V,Vs=0VVd=0.1V,Vb=-0.6V,Vs=0V截距=Vt0+0.5Vds00.000050.00010.000150.00020.0002500.30.60.91.21.5Vds(V)Ids(A)Vgs=0.3VVgs=0.6VVgs=0.9VVgs=1.2VVgs=1.5V饱和区线性区Ion=Idsat(Vgs=Vdd)IonIdlin0.15umLV,W/L=10/10上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation7Confidential亚阈特性曲线1.亚阈摆幅S和Vt0(或Vt1)是影响MOS管漏电的二个重要参数,S越小越好,室温下一般为70~90mV/dec;2.体因子γ一般越小越好;ImVVVVdstgstht()exp2亚阈区：亚阈摆幅(Sub-thresholdSwing)：)(logdsgsIddVS)1(60)1(3.2oxitdoxitdtCCCmVCCCVSVVVthfbffsb221.00E-121.00E-111.00E-101.00E-091.00E-081.00E-071.00E-061.00E-051.00E-041.00E-0300.20.40.60.811.2Vg(V)Id(A)Vd=0.1V,Vb=0V,Vs=0VVd=1.2V,Vb=0V,Vs=0VVd=0.1V,Vb=-0.6V,Vs=0VVt1@1E-7*W/LIoffVt30.15umLV,W/L=10/10上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation8Confidential短沟MOSFET—电流方程•影响短沟管Idsat的因素有：Leff，Vth，μeff，νsat,Rs，Cinv(Teq)。satDsatthgsinvdsatvVVVWCI)(饱和区：effcthgseffcthgsDsatLVVLVVV)()(effsatcv2)1(0satsinvdsatdsatvRWCII考虑Rs/Rd效应时：)(00dsdsatDsatDsatRRIVV上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation9Confidential1.00E-121.00E-101.00E-081.00E-061.00E-041.00E-02-0.200.20.40.60.811.2Vgs(V)Ids(A/um)L=0.135um,Vds=0.1VL=0.135um,Vds=1.2VL=0.15um,Vds=0.1VL=0.15um,Vds=1.2V0.00E+001.00E-032.00E-033.00E-034.00E-035.00E-036.00E-037.00E-038.00E-0300.30.60.91.21.5Vds(V)Ids(A)短沟MOSFET—I-V特性曲线1.沟道越短，DIBL越大；2.DIBL有时会表现为亚阈摆幅增大,即增加Ioff;3.DIBL会降低输出电阻,使器件用于模拟电路特性变差,用于数字电路速度下降.σ=|Vt1–Vt2|/|Vdd-0.1|DIBL(draininducedbarrierlow)：1.00E-091.00E-081.00E-071.00E-061.00E-051.00E-041.00E-031.00E-0200.20.40.60.811.2Vg(V)Id(A)Vd=-0.1VVd=-1.2VVt2@1E-7*W/L0.00E+001.00E-032.00E-033.00E-034.00E-035.00E-0300.20.40.60.811.2Vg(V)Id(A)Vd=-0.1VVd=-1.2V0.15umLV,W/L=10/0.15上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation10ConfidentialIoff-Ion特性曲线1.深亚微米技术改进的一个重要标志是Ioff-Ids曲线右下方向移动,即较大的Ion下Ioff较低.2.亚阈摆幅降低,迁移率提高,Teq降低等都会改善此特性.Ids+~6%IEDM2000,NEC,ShinyaIto,etal.10100100010000400450500550600650Ion(uA/um)Ioff(pA/um)工艺改进0.15umLV上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation11ConfidentialBVoff,Bvon,Ibmax,Igmax•Ibmax是同NMOSHCI寿命密切相关，τ∝1/(Ibmax)3~5;•Igmax则同PMOSHCI寿命密切相关.•器件优化阶段必须考虑,至少不大于目标值.•Bvon和Bvoff也是器件基本电学参数.0.E+002.E-064.E-066.E-068.E-061.E-051.E-051.E-050.01.02.03.04.05.0|Vg|(V)Ig(A)POR+LDDE+LDDE,-LDDdose0.E+005.E+001.E+012.E+012.E+013.E+013.E+014.E+014.E+010.01.02.03.04.05.0|Vg|(V)|Isub|(A)PORLDD,-dose5VNMOSFET5VPMOSFETHVNMOSTCADdata上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation12Confidential1.MOSFET的特性曲线与特征参数2.短沟效应(SCE&RSCE)3.窄沟效应(NWE&RNWE)与STI寄生晶体管上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation13Confidential短沟效应(SCE&RSCE)RSCE(reverseshortchanneleffects)•Vth随沟道缩短而增加;•Vth(L=10um)-Vtmax越小越好，使所有Lmin器件便于电路设计；•机理是Pocket注入和B横向扩散。SCE1.Vth随沟道缩短而变小；2.机理是SDEpn结自建电场引起的耗尽层；3.SDE越深，SCE越严重；4.一般要求Vth(Lrule-1)/Vth(Lrule)90%。Vth(L=10um)-VthmaxVth(rule-1)Vth(rule)0.18umtech.上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation14ConfidentialCDctrl与短沟效应•SCE越小、CDctrl越好，Lg(nom)就可以越小，Idsat就可以更大。练习：一个产品的电路设计时器件尺寸选在Lg(nom)(绿园圈所示),1.红线工艺和黑线工艺比较，CDctrl一定，产品有何优点？2.蓝线工艺和红线工艺比较，CDctrl一定，产品有何优点？Ioff限定时:Lg(nom)=Lg(min)+CDctrl上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation15Confidential1.MOSFET的特性曲线与特征参数2.短沟效应(SCE&RSCE)3.窄沟效应(NWE&RNWE)上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation16ConfidentialNWE&RNWE1.NWE主要是针对LOCOS隔离器件而言，原因是Birdbeak下面栅氧较厚，掺杂较重。2.RNWE是对STI隔离器件(特别是NMOS)而言，主要原因是STIcorner电场增强。3.Vth(Wmin)/Vth(W=10)?上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation17ConfidentialSTIParasiticTransistor1.除了RNWE,STI寄生管还会引起“doublehump”效应，继而引起Ioff增加;2.Doublehump在衬底加压和高温下更加明显。上海宏力半导体制造有限公司GraceSemiconductorManufacturingCorporation18Confidential谢谢各位！请批评指正