OntheleftofthisslidetheamplitudeoftheFouriercoefficientsis
shownfortheordersfromthegratingandtheprojectedorders(
onthewafer).Thisleadstoacomparisonbetweentheperfectima
geandthesumoforders.Ontherightsidethesameisdonefor
agratingwithasmallerpitch.Notethattheevenordersaren
otpresentintheFouriercoefficients!!MOS产品事业部NIKON光刻机光刻要求温度2
3+/-1度，湿度45+/-度13131312121212121212114)Develop
conditions显影液浓度影响显影液温度影响：23度最合适显影时间的影响1.50
2.383.0TMAHConcentra
tionPhotospeedResolutionBetterHigherDeveloptimevsprofile
Developtimevsprofile?time(sec)PROFILE5060409070Optim
umtimeThisisthestandardtooltodecidedevelopdippingtime
.UnderDevelop:ScumandtailOverDevelop:Topprofilecollap
seDEVELOPRATETEMPERTUREDeveloptemperatureisoneofimporta
ntitemtocontroldeveloprate.Ithasoptimumtemp.ButTomainta
inconstanttemperatureisnoteasy.Itdependonspraytypeand
nozzletype.UsuallyEngineerneedtofindoutoptimumtemp.But
usuallywecanuseroomtemperaturebecausethistemp.isthemos
tstabletemperature.3?DeveloptempvsDevelopspeed(rate)3.光
刻工艺交流SwingcurveThereareinterferencebetweeninputandref
lectivelightintheresistfilm.Theamplitudeofstandingwave
isdecidedbywavelength,substrateandARCfilmTheworstcase
isDUVresist(becauseofhighReflectivity)UsingTARCisbest:
TARCreducesstandingwaveeffect.Tprshouldbedecidedbymin
imumCDvariationtarget(Hillorvalleyofstandingwavecurve
FEMDefocus的影响Defocus产生的原因ParticleEdgeEffectAutoFocusAu
toLeveling边缘效应FunctionDecideoptimumz-stageposition(Focus)
beforeshotexposing.INCIDENTBEAMDetector(CCD)?ZZ-MOTION?X
QQ''PROJECTIONLENSMIRRORMIRRORLENSLENS?WAFERLightsourc
e:HalogenlampDetector:7x7(49points)sensorDatafeedback:
z-stage?X=2?Zsin?:When?is90degree,AFsensitivityisbe
stThefeatureofAFsensorisdifferentfromeachvendor.Itdep
endonwafershotposition:Waferedge==>Beamsizeistoolarge
:ShiftfocusThisisnotthesameasAutoLevelingsystem.This
featureshowCanonsystem.Autofocussystem5AutoLeveling
MisalignOffsetInShotMagnificationShotRotationByShotsSca
lingWaferRotationOrthogonilityMisalign光刻胶、显影液等原料工艺评估和验收光刻胶：
spincurve,swingcurve,masklinearity,resolution,
processwindow,etchandimplantresistance显影液：defectm
onitor，resistsprofile,CD,developrate.负胶：曝光后变为交联聚合物
，不溶于显影液；正胶：曝光后光敏剂分解，打断交联化学键负胶：曝光后变为交联聚合物，不溶于显影液；正胶：曝光后光敏剂分
解，打断交联化学键Inthisslideabundleoflight,drawnaswavefron
ts,passesthroughadoubleslit.AccordingtoHuygens’principle
,discussedearlier,thewavefrontswhichpassthegratingact
likenewformedcircularwavefronts.Thesecircularwavefronts
interferetogivemaximumandminimumintensity.TheMaximuminte
nsitiesarecalledorders.Whenthereticleimageisconstant,th
eangleofthediffractedorderswillbebiggerifthewavelength
islonger,i.e.248nmthanifthewavelengthisshorter,i.e.1
93nm.Inthisexample,theverticalparallellinesdefinethe
abilityoftheprocesstoresolveanimage.Thetopdrawingshows
theordersrecombiningatawideangleresultingfromilluminati
onatalongerwavelength,forexample248-nm.Thebottomdrawin
gshowstheordersfromthesamefeaturerecombiningatanarrowe
rangleresultingfromilluminationatashorterwavelength,for
example193-nm.Inbothcases,theprocessresolvesthesamemin
imumimagesize.Howeverinthebottomexamplethedistancefrom
theexactpointofrecombinationoforders(thefocalplane)is
greaterthaninthetopexamplesimplybecausetheangleofdiffr
actionisnotaslarge.Therefore,thebottomexampleallowsag
reatertoleranceinfocusbeforetheabilitytoresolvethismini
mumimagesizeislost.DiffractionordersTheleftsideofthis
illustrationshows(intwodimensions)howthediffractionangle
ofordersbecomesincreasinglylarger(fromnormal)astheorder
increases.Therightsideoftheillustrationaddsdepthtothe
informationontheleft,asiflookingintotheslide.So,what
areweseeing?Ontheright,thefullimplicationofthewavefron
tsreachingthewaferareshown(goingthroughthewafer,asift
ransparent).Thetheoreticalmaskimageisshownatthewaferpl
ane.Startingwiththetopviewonlythed.c.component(0thord
er)ofthedenselinesisshowntobeilluminatingthefullfield
.Thecenterviewshowsonlythepositivefirstorderinformatio
n,anddefineshowthewavefrontapproachesthewaferatitsangl
eofdiffraction.Thebottomviewshowsonlythepositivethird
orderinformation,againdefininghowthewavefrontalsoapproach
esthewaferatitsangleofdiffraction,beingagreaterangle(
3X)thanthatofthefirstorder,andarrivingatthewaferwith
triplethespatialfrequencyofthemaskimage.Thisillustration
explainshowdiffractedinformationisrecombinedtoformanima
ge.Thereticlepatternisagrating:thatis,repeatingclear
andopaquefeatures.Forsuchasituation(50%dutycycle),the
0thorderisadccomponentwhichisequalinamplitudetotheav
erageoflightanddarksegmentsofthegrating.Asthirdorder
informationisresolvedbythelens(largerfeatures),the“sum”
curveatthebottomshowshowtheresultingimageatthefocalpl
anebeginsmoretoresembletheoriginalreticlefeature(square
wave).AlignmentProcessAlignmentMarkLSAvs.FIA对位方式光源优点缺点
LSA激光灵敏度高，识别能力强，适合绝大多数层次不适合铝层及对位标记不对称的情况FIA卤素灯适合铝层及非对称对位标记
对位速度慢，对台阶要求高WaferSearchAlignmentSearchY-T对位；确认圆片旋转；确认Y位置
；确认X位置；进行EGA对位。WaferEGAAlignmentEGACorrectionOffset(um)
Scaling(PPM)WaferRotation(urad)X-YOrthogonality(urad)Shot
Magnification(PPM)对位点个数对对位精度的影响Misalign影响光刻机的一些因素温度：温度对掩模版台
、光学元件、承片台和对准系统产生影响。所以高温照明系统和电源通常放在远离设备主体的地方。湿度：湿度能影响空气密度，不利于光通过；
从而对干涉计定位、透镜数值孔径和聚焦产生不利影响。振动：振动的发生将给定位、对准、聚焦和曝光带来问题。可能产生定位错误、对准错误
、离焦和不均匀曝光。大气压力：大气压力的变化可能影响投影光学系统中空气的折射率。将导致不均匀线宽控制和极差的套准精度。前烘和前
处理涂胶SpinCoating滴胶回吸旋转涂胶EBRReadyforsoftBake涂胶SpinCoati
ng热板加热，wafer直接和热板全面接触，热传导很快，热量从下往上传导。溶剂挥发快。优点：均匀性好！烘箱加热，热量通过空气
传导给wafer，需要时间长，且会存在均匀性问题。微波加热，热量从上往下，光刻胶表面会先变硬，如胶厚度较厚，底下的溶剂不好挥发。
注意事项：Softbake温度过高，会导致曝光能量增大和分辨率降低。因为温度太高，会导致羧酸扩散变差。Softbak
e温度过低，溶剂残留过多，导致光刻胶热稳定性变差。如果测定显影前后光刻胶膜厚的变化较大，增加Softbake温度。驻波效
应—Standingwaveeffect前烘PEBPostexposurebakeWithoutPEBWi
thPEBPEB促使光刻胶里面的羧酸扩散，以及树脂有限度的流动，从而有效减小驻波效应的影响。HMDS、前烘、及PEB之
后的步骤，都需用通过冷板冷却。前烘后，如果没有冷却到23度，直接曝光，则图形变差。PEB后，如果没有冷却，将会导致过显影。
硅片冷却显影显影流程显影形貌坚膜Hardbake2.光刻成像机理和图形控制siliconsubstrate
oxidephotoresistPositivephotoresistimagingtheoryIslandWi
ndowAreasexposedtolightbecomephotosoluble.Resultingpatter
naftertheresistisdeveloped.ShadowonphotoresistExposedar
eaofphotoresistChromeislandonglassmaskphotoresistsilic
onsubstrateoxideUltravioletLightPrintsapatternthatisthe
sameasthepatternonthemask光刻图形的侧墙角度不可能为90度R=k1?/NAD
OF=k2?/(NA)2NA=nsin?ImagePlaneLens?fdn:AirR.I(
?1)图形成像决定因素：波长和透镜的数值孔径影响成像的因素有哪些?1）lenscontrol2）Surfaceco
nditions3)Exposeconditions4)Developconditions5）Heatcondit
ion慧差畸变球差场曲像散球差、慧差、场曲、像散，影响成像清晰度。畸变影响物像相似度Max-min<60nm畸
变并不会影响像的清晰度，而只影响像与物的相似性。畸变，是指物所成的像在形状上的变形。Surfaceconditionsi
nclude:filmcomposition,e.g.:silicon,nitride,polysilicon,me
tal,etc.FlatnesssurfacereflectivitySurfaceconditionsmaya
ffectphotoresist-to-waferadhesionalignmentaccuracylinewidth
resolutionYield2）Surfaceconditions3)ExposeconditionsDose
Defocus:IffocalplanispositionedatoutofDOFboundary,p
atternprofilebecometobechangedduetocontrastimagechange
ShotReticleBladeGuardRingUvLightStagePellicleCrPATTE
RNParticleOutofFocusWaferParticlesizeonthereticleisd
ecidedbyitsprintablityResolutionlimitANDDOF2光刻机的发展31光
刻机基础介绍光刻机的发展光刻机的发展主要从二十世纪70年代到现在，从早期的线宽5微米以上到现在的亚微米尺寸，从汞灯光
源到KrF等，按曝光方式大致将光刻机分为五代。Future步进扫描光刻机分步重复光刻机扫描投影光刻机接触式光刻机接近式
光刻机光刻机的发展工作能力下降减小了分辨能力，获得小的关键尺寸成问题接近式光刻机缓解了沾污问题。机器
容许偏差控制的要求，定位容差要求不超过几十纳米机器制造难度和镜头的制造难度大步进传动误差小于特征尺寸的1/10是一
种混合设备融合了扫描和分步光刻机解决了细线条下CD的均一度为了解决曝光场的限制和关键尺寸减小等问题20世纪80年代后期，可
以使用缩小透镜提高了套刻均一度，提供了高分辨率因为采用1:1的掩模版，若芯片中存在亚微米尺寸，掩模版不能做到无缺
陷20世纪80年代初解决了沾污和边缘衍射接近式光刻机扫描投影光刻机分步重复光刻机步进扫描光刻机接触式、接近式、投
影式光刻机光路示意图分步重复光刻机光路示意图制约分辨率的因素接触式曝光机，膜厚越薄，越有利于提高分辨率。5:1lens
UVUVStepandScanImageFieldScanStepperImageField(single
exposure)4:1lensReticleReticleScanScanWaferWaferStepping
directionRedrawnandusedwithpermissionfromASMLithography
第五代光刻机stepper和scanner的区别扫描光刻机原理ScannerUVlightReticlefield
size20mm×15mm,4dieperfield5:1reductionlensWaferImage
exposureonwafer1/5ofreticlefield4mm×3mm,4dieperex
posureSerpentinesteppingpatternNIKONStepper设备名称介绍NSR2005G8C
NSR——NIKONStepandRepeatExposureSystem20——Max.Exposur
eFieldis20mmSquare05——ReductionRatiois1/5G——G-Linei
sUsedasExposureLightSource8——BodyTypeNumberC——Projec
tionLensType光刻机三巨头光刻机简介ExposureField——NIKONStepperField2
0mm15mmΦ(mm)28.2821.23Max.Width20000×2000015080×14940
Max.Length19166×204009300×18860Square20000×200001501
0×15010主要性能参数k:工艺系数kMIN=0.61NA:数值孔径λ:光源波长G-line(4
36nm)、I-line(365nm)、KrF(248nm)、ArF、F2、…………数值孔径NumericalAp
ertureNA:描述多光学元件透镜系统的性能fDn:透镜折射率2α:像点张角D:透镜直径f:透镜焦距R
esolutionlimit定义为清晰分辨出硅片上间隔很近的特征图形的能力。图形的分辨率与设备的光学特性采用的光刻胶及光刻工
艺环境有关。ResolutionResolutionLIGHESOURCEProcess/resistimprovem
entsImprovedopticalschemesLensdesignimprovementsResolution
limit代价Lowerk1HighNASmallerλ更换光源光源的成本增加，准分子激光的输出功率较小，光刻
胶也需要进行改进DOF越小，意味着镜头的材料改变工艺改进的问题ResolutionlimitFOCUSANDDOF
DOF的定义焦点周围的一个范围，在这个范围内图像连续的保持清晰，这个范围被称为焦深或DOF。描述焦深的方程式是：
K2的数值范围在0.8到1.2之间Diffractionintensityposition0order-1orde
r+1orderSlitDiffractedlightraysPlanelightwaveR=k1?/
NADepthofFocus-1thOrder+1thOrder0thOrderDOFDOFShort
wavelengthLongwavelength+-PhotoresistFilmDepthoffocusCe
nteroffocusLensUV013571357LensQuartzChromeDiffra
ctionpatternsMask下图显示：NA值越大，越能获取1级或者2级的衍射光，分辨率越高。但是，上图显示，NA
值增大，则DOF变小。R=k1?/NADOF=k2?/(NA)2NA=nsin?n=0n
=1n=3ReticlelevelWaferlevelDCbiasResistZeroand+1s
torderwaveformZeroand3rdorderwaveformDiffractionOrdersZ
eroorderwaveformsum+FirstorderThirdorderRecombinationo
fOrdersZeroorderRecombinationofOrdersImagePerfectImages
umoftheordersAmplitudeAmplitudeWaferFourierCoefficients-
0.4-0.200.20.40.60.8012345678910AmplitudeOrder
number-0.4-0.200.20.40.60.8012345678910Order
numberAmplitude-3-10+1+3-10+1-3
+3MaskTechnologyOverviewComparewithAlternativePSMandBin
arymaskonwaferLENSBinaryMaskE-fieldI-fieldCrQ
zLight00+onwaferonwafer0AlternativePSMCrQzLightShi
fterLENS0+-onwafer主要性能参数型号NAλR(k=0.61)R(k=0.80)DOF
1505G7D0.45436nm0.59um0.78um2.15um1505I7A0.45365nm0.49u
m0.65um1.80um1505G6E0.54436nm0.49um0.65um1.50um2005G8C0
.54436nm0.49um0.65um1.50um2005I8B0.50365nm0.45um0.58um1
.46um2005I10C~0.57365nm0.39um0.51um1.12um2005I11D~0.6336
5um0.35um0.46um0.92um对位过程初始化基准标记位置(FoundCoordinates)光刻版对位
(AligntoFiducialMark)园片对位(BaseontheCoordinates)Pre-Alig
nment(FindtheOrientationFlat)SearchAlignmentLSA(LaserSte
pAlignment)FIA(FieldImageAlignment)g-EGAAlignment(Enhance
dGlobalAlignment)LSAFIAwww.hwdz.com.cnwww.hwdz.com.cn光
刻工艺介绍Outline1.光刻工艺及材料2.光刻胶的成像机理3.光刻工艺交流1.光刻工艺及材料光刻就是将掩膜
版上的几何图形转移到涂有一层光刻胶的硅片表面的工艺过程。光刻概述——PHOTOLITHOGRAPHY光刻总的质量要求：
①条宽符合指标要求②套刻精度符合指标要求③胶厚符合指标要求
④无缺陷⑤胶图形具有较好的抗腐蚀能力关键层：①直接影响器件的电学性能或对最终成品率有重
大影响②条宽要求最严格③套刻精度要求最严格光刻概述——PHOTOLITHOGRAPHY
光刻工艺流程HardbakeStripPREtchPreviousProcessIonImplantRej
ectedSurfacepreparationPRcoatingSoftbakeAlignment&Expos
ureDevelopmentInspectionPEBApprovedCleanTracksystemPhoto
BayPhotocellPhotoprocess光刻设备及材料★光刻版★HMDS★光刻胶★显影液★EBR
设备：材料光刻机匀胶机显影机★HMDSHydrophilicSurfaceSubstrateSiSiSi
SiOOOO(H3C)3Si(H3C)3Si(H3C)3Si(H3C)3Si⊿T-nNH3Hydroph
obicSurfaceLowContactAngleHighContactAngleSubstrateSiSi
SiSiOHOHOHOH(H3C)3SiSi(CH3)#NH(H3C)3SiSi(CH3)#NHWe
cancheckwafersurfaceconditionbycontactangleNeedtocle
anthevaporizedgassupplypipetoremoveparticlesource3★HM
DS聚合物材料固体有机材料光照下不发生化学反应作用：保证光刻胶的附着性和抗蚀性，同时也决定光
刻胶的厚度、热稳定性。感光材料(PAC)：被曝光而发生化学反应，改变光刻胶的溶解性正性光刻胶：不可
溶变为可溶负性光刻胶：可溶变为不可溶溶剂：使光刻胶被涂到硅片表面前保持液态添加剂：改变光刻胶
的特性性能，比如降低反射率等。★光刻胶PhotoandPhotoresist★Photore
sistclassify(baseonlightsourceand?)R=k1?/NADOF=k2
?/(NA)2NA=nsin?ImagePlaneLens?fdn:AirR.I(?1)Me
rcurylamp为了得到更小的线条（分辨率），就必须选用更短波长的光源。汞灯中波长小于365nm的光光强太
弱，不能用于化学放大光刻胶中。所以，在248nm以下光刻中，光源选用准分子激光或氟分子激光。它们是单一波长的光。一般stepp
er或scanner的曝光源，都是通过滤光片将其他不需要的光过滤掉，只留下365nm或436nm的光。接触式曝光机一般用宽谱曝光
，即没有将光源的其他光过滤掉。光刻胶的基本要求★EBR——EdgeBeadRemovalEBR化剂的成份一般和
光刻胶的溶剂成份相同。正胶的EBR一般成份为PGMEA(丙二醇甲醚醋酸酯)和PGME(丙二醇甲醚),比例为
30%和70%。EBR除了用于去边、背清之外，也用于金属层之后返工去胶用。EBR的控制点为金属杂质含量。★光刻版——
Reticle(NIKONStepper)www.hwdz.com.cnwww.hwdz.com.cn
负胶：曝光后变为交联聚合物，不溶于显影液；正胶：曝光后光敏剂分解，打断交联化学键负胶：曝光后变为交联聚合物，不溶
于显影液；正胶：曝光后光敏剂分解，打断交联化学键Inthisslideabundleoflight,dra
wnaswavefronts,passesthroughadoubleslit.AccordingtoHuy
gens’principle,discussedearlier,thewavefrontswhichpasst
hegratingactlikenewformedcircularwavefronts.Thesecircul
arwavefrontsinterferetogivemaximumandminimumintensity.T
heMaximumintensitiesarecalledorders.Whenthereticleimage
isconstant,theangleofthediffractedorderswillbebiggerif
thewavelengthislonger,i.e.248nmthanifthewavelengthis
shorter,i.e.193nm.Inthisexample,theverticalparallelli
nesdefinetheabilityoftheprocesstoresolveanimage.Theto
pdrawingshowstheordersrecombiningatawideangleresulting
fromilluminationatalongerwavelength,forexample248-nm.Th
ebottomdrawingshowstheordersfromthesamefeaturerecombini
ngatanarrowerangleresultingfromilluminationatashorterw
avelength,forexample193-nm.Inbothcases,theprocessresolv
esthesameminimumimagesize.Howeverinthebottomexampleth
edistancefromtheexactpointofrecombinationoforders(thef
ocalplane)isgreaterthaninthetopexamplesimplybecausethe
angleofdiffractionisnotaslarge.Therefore,thebottomexa
mpleallowsagreatertoleranceinfocusbeforetheabilitytore
solvethisminimumimagesizeislost.DiffractionordersThelef
tsideofthisillustrationshows(intwodimensions)howthedif
fractionangleofordersbecomesincreasinglylarger(fromnormal
)astheorderincreases.Therightsideoftheillustrationadd
sdepthtotheinformationontheleft,asiflookingintothesl
ide.So,whatareweseeing?Ontheright,thefullimplication
ofthewavefrontsreachingthewaferareshown(goingthroughthe
wafer,asiftransparent).Thetheoreticalmaskimageisshown
atthewaferplane.Startingwiththetopviewonlythed.c.com
ponent(0thorder)ofthedenselinesisshowntobeilluminating
thefullfield.Thecenterviewshowsonlythepositivefirsto
rderinformation,anddefineshowthewavefrontapproachesthewa
feratitsangleofdiffraction.Thebottomviewshowsonlythe
positivethirdorderinformation,againdefininghowthewavefron
talsoapproachesthewaferatitsangleofdiffraction,beingagreaterangle(3X)thanthatofthefirstorder,andarrivingatthewaferwithtriplethespatialfrequencyofthemaskimage.Thisillustrationexplainshowdiffractedinformationisrecombinedtoformanimage.Thereticlepatternisagrating:thatis,repeatingclearandopaquefeatures.Forsuchasituation(50%dutycycle),the0thorderisadccomponentwhichisequalinamplitudetotheaverageoflightanddarksegmentsofthegrating.Asthirdorderinformationisresolvedbythelens(largerfeatures),the“sum”curveatthebottomshowshowtheresultingimageatthefocalplanebeginsmoretoresembletheoriginalreticlefeature(squarewave).OntheleftofthisslidetheamplitudeoftheFouriercoefficientsisshownfortheordersfromthegratingandtheprojectedorders(onthewafer).Thisleadstoacomparisonbetweentheperfectimageandthesumoforders.Ontherightsidethesameisdoneforagratingwithasmallerpitch.NotethattheevenordersarenotpresentintheFouriercoefficients!!MOS产品事业部NIKON光刻机光刻要求温度23+/-1度，湿度45+/-度1313131212121212121211 |
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