基于扫描电镜的电子束曝光系统Raith

.,基于扫描电镜的电子束曝光系统RaithGmbHElphyplus,.,主要内容,扫描电子显微镜介绍Raith电子束曝光系统电子束曝光图形制作曝光参数对准操作纳米器件制作的主要步骤,.,XL30SFEG(atopperformingfieldemissionSEM),Accelerationvoltage:200V30kVResolution:1.5nmat10kV,2.5nmat1kVElectronspot1nm,Resolution1nmSTEMwithinSEM!+CLdetector,.,.,电子发射枪,.,电子透镜原理,.,.,Electrongunproducesbeamofmonochromaticelectrons.Firstcondenserlensformsbeamandlimitscurrent(coarseknob).Condenserapertureeliminateshigh-angleelectrons.Secondcondenserlensformsthinner,coherentbeam(fineknob).Objectiveaperture(usu.user-selectable)furthereliminateshigh-angleelectronsfrombeam.,.,Beamscannedbydeflectioncoilstoformimage.Finalobjectivelensfocusesbeamontospecimen.Beaminteractswithsampleandoutgoingelectronsaredetected.Detectorcountselectronsatgivenlocationanddisplaysintensity.Processrepeateduntilscanisfinished(usu.30frames/sec).,.,Cathodaluminescence,Secondarye,Backscatterede,Incidente,ElasticallyScatterede,InelasticallyScatterede,Unscatterede,X-rays,Augere,电子相互作用,.,Causedbyincidentelectronpassingnearsampleatomandionizinganelectron(inelasticprocess).Ionizedelectronleavessamplewithverysmallkineticenergy(5eV)andiscalledsecondaryelectron.(Eachincidentelectroncanproduceseveralsecondaryelectrons.)Productionofsecondaryelectronsistopographyrelated.Onlysecondariesnearsurface(10nm)exitsample.,FEWERsecondaryeescape,MOREsecondaryeescape,二次电子的形成,.,如何生成二次电子像,Secondaryelectronsaregeneratedbytheinteractionoftheincidentelectronbeamandthesample.Thesecondaryelectronsemergeatallangles.Theseelectronsgatheredbyelectrostaticallyattractingthemtothedetector.Knowingboththeintensityofsecondaryelectronsemittedandpositionofthebeam,animageisconstructedelectronically.,.,Raith电子束曝光系统,曝光精度30nm,器件套刻精度50nm,.,Beamblanker,图形发生器,BeamblankerAmplifier,控制系统界面,.,Beamblanking,.,Faraday圆筒测电流,.,工作方式高斯束、矢量扫描、固定工作台,.,Elphyplus主控制界面,.,曝光图形的制作,图形格式：.CSF或者.GDS,常用软件：elphyplusGDSIIdatabaseLeditAutoCAD等等,曝光之前，必须先知道曝什么！,.,增加图层,.,选定图层,.,选定图层,.,显示绘图格点,.,改变绘图格点间距,.,选用画笔,.,.,.,.,曝光图形设计注意事项,最小尺寸：线宽、间距（考虑临近效应）对准标记要适合（多用十字）需要曝光的图形要远离对准标记两层之间的对准要留容错注意曝光的顺序注意图形交叠，特别是场拼接处的图形,.,d,.,.,曝光中的主要操作对准,1、源漏电极要压在纳米管上2、栅电极要盖在源漏之间,难点：很多地方不能看！,.,对准调节,曝光之前，必须先知道在哪里曝光！,扫描电镜的坐标（x,y）,曝光系统定义的坐标（u,v）,.,两套坐标的刻度校准,.,标准样品,.,.,.,三点校正确定u、v坐标,（1.0,0）(1.5,0)(1.5,0.5),第一次三点校正,.,.,第二次三点校正,（1.07,1.05）,（1.43,1.05）,（1.45,1.43）,.,.,.,曝光参数设置扫描电镜,加速电压如：20kVSpotsize工作高度选择,.,曝光参数设置Elphyplus,图层选择电流密度曝光剂量移动步距,.,.,曝光剂量的选